Re: [Emc-users] Fiber optic control for CNC

[Gene Heskett]

On Saturday 29 April 2017 15:17:23 dave wrote:

> I finally climbed my shelving and checked the fiber. I found (maybe
> 200') of 2.8mm x 2.0 mm. No other information on the reel. In addition
> I checked one of my reels of 62.5/125 um Berk-tek plenum fiber. At
> least one end is terminated in hot-melt connectors: what ever that
> means. It has simply been too long. The reel for the 2.0 mm I think
> exceeds the min bending radius for the 62.5/125 so I could add some of
> that to the spool with the plastic. Shipping still won't be cheap.
> Obviously, no obligation, unless you just can't resist. ;-)
>
> Dave
>
I couldn't get any usefull info from the peddlers of fittings for several 
hours on the phone Monday, so I told myself to forget it.  If they don't 
want to sell the stuff, I can't force them.

Just this afternoon I thru together 4 channels worth of snubbers made out 
of 1n914's & small bypass caps, which at a fwd drop per each means 6 in 
series is 3.55 volts, so anything that goes above about 3.6 volts will 
get shorted out, or anything going below ground by more than .585 volts 
will get gobbled up. Then I hooked up a poor sub for the home switch I 
was going to use, but its repeatability is 3 or 4 thou at best with a 
deadband of nearly 60 thou.  That  won't do. I do have one more "good" 
switch but its spst no and I'd druther have nc. And tommorrow is the 
last day for the last radio shack within 140 miles, maybe all of them.  
So I'll have to fleabay some & see how repeatable they are I guess.

Thanks for the checking though Dave, I appreciate it.

>
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Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] Fiber optic control for CNC

[dave]

I finally climbed my shelving and checked the fiber. I found (maybe 
200') of 2.8mm x 2.0 mm. No other information on the reel. In addition I 
checked one of my reels of 62.5/125 um Berk-tek plenum fiber. At least 
one end is terminated in hot-melt connectors: what ever that means. It 
has simply been too long. The reel for the 2.0 mm I think exceeds the 
min bending radius for the 62.5/125 so I could add some of that to the 
spool with the plastic. Shipping still won't be cheap. Obviously, no 
obligation, unless you just can't resist. ;-)

Dave



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Re: [Emc-users] Fiber optic control for CNC

[Gene Heskett]

On Monday 24 April 2017 13:11:08 Chris Albertson wrote:

> On Mon, Apr 24, 2017 at 3:05 AM, Gene Heskett  
wrote:
> > On Monday 24 April 2017 01:17:33 dave wrote:
> > > On 04/23/2017 08:30 PM, Gene Heskett wrote:
> > > > On Sunday 23 April 2017 23:14:34 dave wrote:
> > > >> On 04/23/2017 12:44 PM, Chris Albertson wrote:
> > > >>> Looks like this is a dead end technology.  Everyone has gone
> > > >>> with HDMI.
> > > >>>
> > > >>> But really you don't need much to send a differential signal
> > > >>> to a stepper driver Anything that can invert a 5V logic signal
> > > >>> will work. The drivers don't want RS422 levels, just logic
> > > >>> levels.  and the receiver is built into the driver
> > > >>>
> > > >>>
> > > >>> But today deferential pairs are outperforming older fiber
> > > >>> technology by orders of magnitude.   toslink is dead easy to
> > > >>> use but its s at least 30 years old.  The best serial cables
> > > >>> on the consumer mass market are going a few ten's a giga bits
> > > >>> per second.
> > > >>>
> > > >>> On Sun, Apr 23, 2017 at 10:18 AM, Gene Heskett
> > > >>> 
> > > >
> > > > wrote:
> > >  On Sunday 23 April 2017 10:03:21 dave wrote:
> > > > the foxcon stuff looks a bit pricey. However ...
> > > >
> > > > http://www.mouser.com/Toshiba/Optoelectronics/Fiber-Optics/F
> > > >iber -O ptic
> > > > -Transmitters-Receivers-Transceivers/TOSLINK/_/N-6qrgo?P=1z0
> > > >zkx4 Z1 ybqc2 q
> > > >
> > > > It actually looks affordable including cables. 10 Mb/s but
> > > > that should handle anything linuxcnc needs. 10' simplex
> > > > cables for a couple of $.
> > > >
> > > > https://www.monoprice.com/Product?p_id=2669=Cj0KEQjwof
> > > >HHBR DS 0Pnh
> > > > pef89ucBEiQASEp6LIW3Tu9rI-YsCuV7XvPZJEDJ4M80OU09A9vYGSpppjMa
> > > >Ajjx 8P 8HAQ
> > > >
> > > > Dave
> > > 
> > >  Only 2 transmitter modules stocked at well over a 10 dollar
> > >  bill each. No receiver modules are stocked at any price. All
> > >  hat, no cattle.
> > > 
> > >  That is a good enough price on ready-made cables if I wanted
> > >  to do it with to$link.  But the above  hardware pricing is
> > >  not a viable choice when you need lots of them. I have no
> > >  intention of spending north of $600 for 10 fiber links.
> > > 
> > >  Good info Dave, thanks.
> > > >>
> > > >> So what you really need ??? is inexpensive Rx and Tx  and then
> > > >> plastic fiber plus an epoxy to bond the
> > > >> two with low losses into a usable static configuration. Eh?
> > > >>
> > > >> Dave
> > > >
> > > > You are getting warmer, Dave, although I'd druther use go2 or
> > > > goop as there's a small chance of getting it apart again should
> > > > it be needed.
> > > >
> > > > Cheers, Gene Heskett
> > >
> > > AFIK you want a clear adhesive with a refractive index close to
> > > 1.49 to match the PMMA core of the fiber.
> > >
> > > Dave
> >
> > The adhesive, as long as it doesn't touch the core, only the jacket,
> > shouldn't be optically important.
>
> No,  the "goop" absolutely HAS to touch the core file.  An "air gap"
> absolutely will not work.  The invention of this special refractive
> index gell is what made it possible for normal humans to field
> terminate fiber. Now days the modern connector only has to hold the
> fiber is alignment then this gell is squeezed in under pressure and
> fils the air gap.
>
> In the old days they used to need to optically polish the fiber ends
> but now the "goop" is automatically pushed into the fractured end of
> the fiber by the connector.Here is a video (link below) that shows
> how a modern connector is used.
>
> He does say in the video that the "old kind" is still used but today
> only in a factory environment.
>
> These connectors are not cheap and still require practice. You will
> water a bunch of them learning how to use them) Better to buy "patch
> cords" that are pre terminated.  OK to TOSLINK is no longer the way to
> go.   Fiber Ethernet is common, try that.
>
> This video is good https://youtu.be/SthwoIDprrk
>
Informative.

But having spent a couple hours on the phone, and 2 more in chats with 
tech support, without finding anyone interested in selling less than 10k 
qty's, I guess I am about burned out on the idea.

Since I've managed to come up with a snubber circuit to put between an 
input to the 7i90, and have enough 1N914's either on hand or in the USPO 
system, and some circuit boards to make them on, I guess that is the 
path I'll take. 5 ea 1n914's from ground to the signal line, anode up, 
makes a good clipper, and a single one paralleling the 5, but cathode up 
seems to prevent below ground undershoots from hurting the 7i90's 
inputs, and a .005 ceramic across the lot which gobbles up at least 90% 
of the noise, is working well over 15' of cat-6 jumper cable and no 
shielding to speak of. pwr & ground on one pair, a pair each 

Re: [Emc-users] Fiber optic control for CNC

[Chris Albertson]

On Mon, Apr 24, 2017 at 3:05 AM, Gene Heskett  wrote:

> On Monday 24 April 2017 01:17:33 dave wrote:
>
> > On 04/23/2017 08:30 PM, Gene Heskett wrote:
> > > On Sunday 23 April 2017 23:14:34 dave wrote:
> > >> On 04/23/2017 12:44 PM, Chris Albertson wrote:
> > >>> Looks like this is a dead end technology.  Everyone has gone with
> > >>> HDMI.
> > >>>
> > >>> But really you don't need much to send a differential signal to a
> > >>> stepper driver Anything that can invert a 5V logic signal will
> > >>> work. The drivers don't want RS422 levels, just logic levels.  and
> > >>> the receiver is built into the driver
> > >>>
> > >>>
> > >>> But today deferential pairs are outperforming older fiber
> > >>> technology by orders of magnitude.   toslink is dead easy to use
> > >>> but its s at least 30 years old.  The best serial cables on the
> > >>> consumer mass market are going a few ten's a giga bits per second.
> > >>>
> > >>> On Sun, Apr 23, 2017 at 10:18 AM, Gene Heskett
> > >>> 
> > >
> > > wrote:
> >  On Sunday 23 April 2017 10:03:21 dave wrote:
> > > the foxcon stuff looks a bit pricey. However ...
> > >
> > > http://www.mouser.com/Toshiba/Optoelectronics/Fiber-Optics/Fiber
> > >-O ptic
> > > -Transmitters-Receivers-Transceivers/TOSLINK/_/N-6qrgo?P=1z0zkx4
> > >Z1 ybqc2 q
> > >
> > > It actually looks affordable including cables. 10 Mb/s but that
> > > should handle anything linuxcnc needs. 10' simplex cables for a
> > > couple of $.
> > >
> > > https://www.monoprice.com/Product?p_id=2669=Cj0KEQjwofHHBR
> > >DS 0Pnh
> > > pef89ucBEiQASEp6LIW3Tu9rI-YsCuV7XvPZJEDJ4M80OU09A9vYGSpppjMaAjjx
> > >8P 8HAQ
> > >
> > > Dave
> > 
> >  Only 2 transmitter modules stocked at well over a 10 dollar bill
> >  each. No receiver modules are stocked at any price. All hat, no
> >  cattle.
> > 
> >  That is a good enough price on ready-made cables if I wanted to
> >  do it with to$link.  But the above  hardware pricing is not a
> >  viable choice when you need lots of them. I have no intention of
> >  spending north of $600 for 10 fiber links.
> > 
> >  Good info Dave, thanks.
> > >>
> > >> So what you really need ??? is inexpensive Rx and Tx  and then
> > >> plastic fiber plus an epoxy to bond the
> > >> two with low losses into a usable static configuration. Eh?
> > >>
> > >> Dave
> > >
> > > You are getting warmer, Dave, although I'd druther use go2 or goop
> > > as there's a small chance of getting it apart again should it be
> > > needed.
> > >
> > > Cheers, Gene Heskett
> >
> > AFIK you want a clear adhesive with a refractive index close to 1.49
> > to match the PMMA core of the fiber.
> >
> > Dave
>
> The adhesive, as long as it doesn't touch the core, only the jacket,
> shouldn't be optically important.
>

No,  the "goop" absolutely HAS to touch the core file.  An "air gap"
absolutely will not work.  The invention of this special refractive index
gell is what made it possible for normal humans to field terminate fiber.
Now days the modern connector only has to hold the fiber is alignment then
this gell is squeezed in under pressure and fils the air gap.

In the old days they used to need to optically polish the fiber ends but
now the "goop" is automatically pushed into the fractured end of the fiber
by the connector.Here is a video (link below) that shows how a modern
connector is used.

He does say in the video that the "old kind" is still used but today only
in a factory environment.

These connectors are not cheap and still require practice. You will water a
bunch of them learning how to use them) Better to buy "patch cords" that
are pre terminated.  OK to TOSLINK is no longer the way to go.   Fiber
Ethernet is common, try that.

This video is good https://youtu.be/SthwoIDprrk

Today I'd use fiber only for longer runs of high speed data.   Say 10
Gigabit over a few hundred meters as normal cat 5 wire does 1 Gigabit just
fine over the distances in a normal office floor.


> My dropping the card for enough of everything to make about 20
> connections, is still dependent on finding a source of bare 2mm OD
> fiber, getting say 250 meters of it, and the stripping tool if it
> exists.
>
> Cheers, Gene Heskett
> --
> "There are four boxes to be used in defense of liberty:
>  soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author)
> Genes Web page 
>
> 
> --
> Check out the vibrant tech community on one of the world's most
> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
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>



-- 

Chris Albertson
Redondo Beach, California

Re: [Emc-users] Fiber optic control for CNC

[Gene Heskett]

On Monday 24 April 2017 01:17:33 dave wrote:

> On 04/23/2017 08:30 PM, Gene Heskett wrote:
> > On Sunday 23 April 2017 23:14:34 dave wrote:
> >> On 04/23/2017 12:44 PM, Chris Albertson wrote:
> >>> Looks like this is a dead end technology.  Everyone has gone with
> >>> HDMI.
> >>>
> >>> But really you don't need much to send a differential signal to a
> >>> stepper driver Anything that can invert a 5V logic signal will
> >>> work. The drivers don't want RS422 levels, just logic levels.  and
> >>> the receiver is built into the driver
> >>>
> >>>
> >>> But today deferential pairs are outperforming older fiber
> >>> technology by orders of magnitude.   toslink is dead easy to use
> >>> but its s at least 30 years old.  The best serial cables on the
> >>> consumer mass market are going a few ten's a giga bits per second.
> >>>
> >>> On Sun, Apr 23, 2017 at 10:18 AM, Gene Heskett
> >>> 
> >
> > wrote:
>  On Sunday 23 April 2017 10:03:21 dave wrote:
> > the foxcon stuff looks a bit pricey. However ...
> >
> > http://www.mouser.com/Toshiba/Optoelectronics/Fiber-Optics/Fiber
> >-O ptic
> > -Transmitters-Receivers-Transceivers/TOSLINK/_/N-6qrgo?P=1z0zkx4
> >Z1 ybqc2 q
> >
> > It actually looks affordable including cables. 10 Mb/s but that
> > should handle anything linuxcnc needs. 10' simplex cables for a
> > couple of $.
> >
> > https://www.monoprice.com/Product?p_id=2669=Cj0KEQjwofHHBR
> >DS 0Pnh
> > pef89ucBEiQASEp6LIW3Tu9rI-YsCuV7XvPZJEDJ4M80OU09A9vYGSpppjMaAjjx
> >8P 8HAQ
> >
> > Dave
> 
>  Only 2 transmitter modules stocked at well over a 10 dollar bill
>  each. No receiver modules are stocked at any price. All hat, no
>  cattle.
> 
>  That is a good enough price on ready-made cables if I wanted to
>  do it with to$link.  But the above  hardware pricing is not a
>  viable choice when you need lots of them. I have no intention of
>  spending north of $600 for 10 fiber links.
> 
>  Good info Dave, thanks.
> >>
> >> So what you really need ??? is inexpensive Rx and Tx  and then
> >> plastic fiber plus an epoxy to bond the
> >> two with low losses into a usable static configuration. Eh?
> >>
> >> Dave
> >
> > You are getting warmer, Dave, although I'd druther use go2 or goop
> > as there's a small chance of getting it apart again should it be
> > needed.
> >
> > Cheers, Gene Heskett
>
> AFIK you want a clear adhesive with a refractive index close to 1.49
> to match the PMMA core of the fiber.
>
> Dave

The adhesive, as long as it doesn't touch the core, only the jacket, 
shouldn't be optically important.

My dropping the card for enough of everything to make about 20 
connections, is still dependent on finding a source of bare 2mm OD 
fiber, getting say 250 meters of it, and the stripping tool if it 
exists.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] Fiber optic control for CNC

[dave]

On 04/23/2017 08:30 PM, Gene Heskett wrote:
> On Sunday 23 April 2017 23:14:34 dave wrote:
>
>> On 04/23/2017 12:44 PM, Chris Albertson wrote:
>>> Looks like this is a dead end technology.  Everyone has gone with
>>> HDMI.
>>>
>>> But really you don't need much to send a differential signal to a
>>> stepper driver Anything that can invert a 5V logic signal will work.
>>>   The drivers don't want RS422 levels, just logic levels.  and the
>>> receiver is built into the driver
>>>
>>>
>>> But today deferential pairs are outperforming older fiber technology
>>> by orders of magnitude.   toslink is dead easy to use but its s at
>>> least 30 years old.  The best serial cables on the consumer mass
>>> market are going a few ten's a giga bits per second.
>>>
>>> On Sun, Apr 23, 2017 at 10:18 AM, Gene Heskett 
> wrote:
 On Sunday 23 April 2017 10:03:21 dave wrote:
> the foxcon stuff looks a bit pricey. However ...
>
> http://www.mouser.com/Toshiba/Optoelectronics/Fiber-Optics/Fiber-O
> ptic
> -Transmitters-Receivers-Transceivers/TOSLINK/_/N-6qrgo?P=1z0zkx4Z1
> ybqc2 q
>
> It actually looks affordable including cables. 10 Mb/s but that
> should handle anything linuxcnc needs. 10' simplex cables for a
> couple of $.
>
> https://www.monoprice.com/Product?p_id=2669=Cj0KEQjwofHHBRDS
> 0Pnh
> pef89ucBEiQASEp6LIW3Tu9rI-YsCuV7XvPZJEDJ4M80OU09A9vYGSpppjMaAjjx8P
> 8HAQ
>
> Dave
 Only 2 transmitter modules stocked at well over a 10 dollar bill
 each. No receiver modules are stocked at any price. All hat, no
 cattle.

 That is a good enough price on ready-made cables if I wanted to do
 it with to$link.  But the above  hardware pricing is not a viable
 choice when you need lots of them. I have no intention of spending
 north of $600 for 10 fiber links.

 Good info Dave, thanks.
>> So what you really need ??? is inexpensive Rx and Tx  and then plastic
>> fiber plus an epoxy to bond the
>> two with low losses into a usable static configuration. Eh?
>>
>> Dave
> You are getting warmer, Dave, although I'd druther use go2 or goop as
> there's a small chance of getting it apart again should it be needed.
>
> Cheers, Gene Heskett
AFIK you want a clear adhesive with a refractive index close to 1.49 to 
match the PMMA core of the fiber.

Dave

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Re: [Emc-users] Fiber optic control for CNC

[Gene Heskett]

On Sunday 23 April 2017 23:14:34 dave wrote:

> On 04/23/2017 12:44 PM, Chris Albertson wrote:
> > Looks like this is a dead end technology.  Everyone has gone with
> > HDMI.
> >
> > But really you don't need much to send a differential signal to a
> > stepper driver Anything that can invert a 5V logic signal will work.
> >  The drivers don't want RS422 levels, just logic levels.  and the
> > receiver is built into the driver
> >
> >
> > But today deferential pairs are outperforming older fiber technology
> > by orders of magnitude.   toslink is dead easy to use but its s at
> > least 30 years old.  The best serial cables on the consumer mass
> > market are going a few ten's a giga bits per second.
> >
> > On Sun, Apr 23, 2017 at 10:18 AM, Gene Heskett  
wrote:
> >> On Sunday 23 April 2017 10:03:21 dave wrote:
> >>> the foxcon stuff looks a bit pricey. However ...
> >>>
> >>> http://www.mouser.com/Toshiba/Optoelectronics/Fiber-Optics/Fiber-O
> >>>ptic
> >>> -Transmitters-Receivers-Transceivers/TOSLINK/_/N-6qrgo?P=1z0zkx4Z1
> >>>ybqc2 q
> >>>
> >>> It actually looks affordable including cables. 10 Mb/s but that
> >>> should handle anything linuxcnc needs. 10' simplex cables for a
> >>> couple of $.
> >>>
> >>> https://www.monoprice.com/Product?p_id=2669=Cj0KEQjwofHHBRDS
> >>>0Pnh
> >>> pef89ucBEiQASEp6LIW3Tu9rI-YsCuV7XvPZJEDJ4M80OU09A9vYGSpppjMaAjjx8P
> >>>8HAQ
> >>>
> >>> Dave
> >>
> >> Only 2 transmitter modules stocked at well over a 10 dollar bill
> >> each. No receiver modules are stocked at any price. All hat, no
> >> cattle.
> >>
> >> That is a good enough price on ready-made cables if I wanted to do
> >> it with to$link.  But the above  hardware pricing is not a viable
> >> choice when you need lots of them. I have no intention of spending
> >> north of $600 for 10 fiber links.
> >>
> >> Good info Dave, thanks.
>
> So what you really need ??? is inexpensive Rx and Tx  and then plastic
> fiber plus an epoxy to bond the
> two with low losses into a usable static configuration. Eh?
>
> Dave

You are getting warmer, Dave, although I'd druther use go2 or goop as 
there's a small chance of getting it apart again should it be needed. 

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

--
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Re: [Emc-users] Fiber optic control for CNC

[dave]

On 04/23/2017 12:44 PM, Chris Albertson wrote:
> Looks like this is a dead end technology.  Everyone has gone with HDMI.
>
> But really you don't need much to send a differential signal to a stepper
> driver Anything that can invert a 5V logic signal will work.  The drivers
> don't want RS422 levels, just logic levels.  and the receiver is built into
> the driver
>
>
> But today deferential pairs are outperforming older fiber technology by
> orders of magnitude.   toslink is dead easy to use but its s at least 30
> years old.  The best serial cables on the consumer mass market are going a
> few ten's a giga bits per second.
>
> On Sun, Apr 23, 2017 at 10:18 AM, Gene Heskett  wrote:
>
>> On Sunday 23 April 2017 10:03:21 dave wrote:
>>
>>> the foxcon stuff looks a bit pricey. However ...
>>>
>>> http://www.mouser.com/Toshiba/Optoelectronics/Fiber-Optics/Fiber-Optic
>>> -Transmitters-Receivers-Transceivers/TOSLINK/_/N-6qrgo?P=1z0zkx4Z1ybqc2
>>> q
>>>
>>> It actually looks affordable including cables. 10 Mb/s but that should
>>> handle anything linuxcnc needs. 10' simplex cables for a couple of $.
>>>
>>> https://www.monoprice.com/Product?p_id=2669=Cj0KEQjwofHHBRDS0Pnh
>>> pef89ucBEiQASEp6LIW3Tu9rI-YsCuV7XvPZJEDJ4M80OU09A9vYGSpppjMaAjjx8P8HAQ
>>>
>>> Dave
>> Only 2 transmitter modules stocked at well over a 10 dollar bill each.
>> No receiver modules are stocked at any price. All hat, no cattle.
>>
>> That is a good enough price on ready-made cables if I wanted to do it
>> with to$link.  But the above  hardware pricing is not a viable choice
>> when you need lots of them. I have no intention of spending north of
>> $600 for 10 fiber links.
>>
>> Good info Dave, thanks.
>>
So what you really need ??? is inexpensive Rx and Tx  and then plastic 
fiber plus an epoxy to bond the
two with low losses into a usable static configuration. Eh?

Dave

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Re: [Emc-users] Fiber optic control for CNC

[Gregg Eshelman]

Circling back to the start of this thread, these guys already did the work.
http://hackaday.com/2016/03/20/add-fiber-optic-control-to-your-cnc/
On Sunday, April 23, 2017, 10:06:55 AM MDT, Gene Heskett  
wrote:On Sunday 23 April 2017 06:47:12 Gene Heskett wrote:

> On Sunday 23 April 2017 02:03:02 Chris Albertson wrote:
> > Gene,
> > They do make such devices. But there is one fundamental difference
> > between a fiber cable and an isolator, the cable can have any length
> > and hence a WIDE range if attenuation.    The cable could be short
> > and with high quality termination and low losses in the conniptions
> > of it could be very long with poorly made terminals
> >
> > So the transmitter / receiver has to be able to handle a couple
> > others of magnitude different attenuation rates.
> >
> > Look on page 2 of the below  linked document The figures describe
> > EXACTLY what you are asking for and it even compares it to an
> > isolator like you did
> > http://media.digikey/fiber-optic%20devices%20toslink.pdf
> >  >ic %20devices%20toslink.pdf>
>
> I will look when its daylight and I've got a cuppa and one eye open.
>
> Thanks.

Having arrived at a state with a cup of caffeine handy, and at least one 
eye open at the same time, I see that the toslink stuff @ $2 plus a 
connector, is rated dc to 15 megabaud, and can handle APF (all plastic 
fiber) up to 10 meters long.  That would work, at a cost per copper wire 
eliminated in the $5 to $20 range depending on the cost of toslink 
terminated cables.  And that cost rather handily takes it out of the 
picture when I can buy the non-toslink stuffs at about a buck a wire 
equ, plus the needed length of APF cable, currently UNK.  Cable that 
when the end has been prepared, is simply pushed into the 20 cent rx or 
rx terminator over the smd led or phototransistor.

> > DIgikey sells the stuff and its cheap because these parts are used
> > in consumer electronics and produced by the millions.
>
> Precisely what I am looking for.

Yes, until you throw in the royalties for using the word toslink, which 
multiplies the cost considerably.  Plus that connector is physically 
large to facilitate gripping it and plugging it in or out, something we 
would only need to do while troubleshooting.

These fibers I have in mind could probably be removed from the connector 
once it work, and given a thin coat of goop or go2 a quarter inch from 
the end, inserted back into the connector and forgotten for 20 years, 
and do it on .2" centers on the interface board. The biggest problem is 
at the rx end where a good stiff pulldown is needed to drive the opto's 
in the driver. That may require a booster transistor, depending on the 
choice of an rx ic.  Those I haven't researched extensively yet because 
I want to call a few fiber vendors tomorrow and get a price on a roll of 
size matching APF, and what the prep tool costs.  I'd love it if the 
fiber could  be directly inserted into a fiber socket in the driver, 
eliminating another translation in the drivers opto isolators.  But 
thats not going to happen until there is a market for those.  And right 
now, I'm a market sample of one. :(  If we could get a maker like 
Tormach onboard, that might be a big enough niche to fill.

[...]

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] Fiber optic control for CNC

[Chris Albertson]

Looks like this is a dead end technology.  Everyone has gone with HDMI.

But really you don't need much to send a differential signal to a stepper
driver Anything that can invert a 5V logic signal will work.  The drivers
don't want RS422 levels, just logic levels.  and the receiver is built into
the driver


But today deferential pairs are outperforming older fiber technology by
orders of magnitude.   toslink is dead easy to use but its s at least 30
years old.  The best serial cables on the consumer mass market are going a
few ten's a giga bits per second.

On Sun, Apr 23, 2017 at 10:18 AM, Gene Heskett  wrote:

> On Sunday 23 April 2017 10:03:21 dave wrote:
>
> > the foxcon stuff looks a bit pricey. However ...
> >
> > http://www.mouser.com/Toshiba/Optoelectronics/Fiber-Optics/Fiber-Optic
> >-Transmitters-Receivers-Transceivers/TOSLINK/_/N-6qrgo?P=1z0zkx4Z1ybqc2
> >q
> >
> > It actually looks affordable including cables. 10 Mb/s but that should
> > handle anything linuxcnc needs. 10' simplex cables for a couple of $.
> >
> > https://www.monoprice.com/Product?p_id=2669=Cj0KEQjwofHHBRDS0Pnh
> >pef89ucBEiQASEp6LIW3Tu9rI-YsCuV7XvPZJEDJ4M80OU09A9vYGSpppjMaAjjx8P8HAQ
> >
> > Dave
>
> Only 2 transmitter modules stocked at well over a 10 dollar bill each.
> No receiver modules are stocked at any price. All hat, no cattle.
>
> That is a good enough price on ready-made cables if I wanted to do it
> with to$link.  But the above  hardware pricing is not a viable choice
> when you need lots of them. I have no intention of spending north of
> $600 for 10 fiber links.
>
> Good info Dave, thanks.
> >
> > --
> > Check out the vibrant tech community on one of the world's
> > most engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> > ___
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> > https://lists.sourceforge.net/lists/listinfo/emc-users
>
>
> Cheers, Gene Heskett
> --
> "There are four boxes to be used in defense of liberty:
>  soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author)
> Genes Web page 
>
> 
> --
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Re: [Emc-users] Fiber optic control for CNC

[Gene Heskett]

On Sunday 23 April 2017 10:41:06 Ralph Stirling wrote:

> Gene,
>
> You might find it useful look at how industrial sensors do this.  I
> use a lot of Automation Direct fiber prox sensors. They have both
> thru-beam and diffuse reflective types.  In any case, they always have
> lenses on the ends of the fibers.
>
> https://www.automationdirect.com/adc/Shopping/Catalog/Sensors_-z-_Enco
>ders/Fiber_Optic_Sensors/SSF_Fiber_Sensors
>
Not at that price level Ralph, way out of reach. Thanks for the link, 
educational to be sure.

> They have a couple of different sensor heads.  For reflective
> applications, I prefer the devices with programmable threshold and
> gain. Non-adjustable ones are ok for thru-beam.
>
> It may be possible to use consumer optical link parts to replicate
> these sensors, but not as simple as it first appears.  The key is
> focusing the light at the fiber end.  You might try a $2 laser pointer
> module for the transmitter side to see if coherent light will reduce
> the need for a lens.  It may lose its coherence in the fiber though.
>
> -- Ralph
>
> On Apr 22, 2017 6:25 PM, Gene Heskett  wrote:
>
> On Saturday 22 April 2017 20:03:05 dave wrote:
> > Gene,
> > I thought about the limit switch thing years ago. The problem is
> > getting enough energy into a small fiber.
> > 62.5 um is not a large target. However, 900 um fiber if you can find
> > it might be just right. For short runs even plastic fiber should
> > work.
> >
> > Dave
>
> This stuff I'm looking at is plastic, a 1.2mm core with a 2.0mm
> jacket. Plastic of course. The longest run would in the 16 feet range.
>
> Step-dir lines to the drivers maybe 40".  At the response times I'd
> expect, losses should not be that bad even in plastic.
>
> I watched the local cable folks install a fiber link from our studio
> output to the cable head end in Enterprise WV, 39 klicks long as the
> cable went. This was in about 1998.  Had to send the splicer back and
> get new knives or something in it, but when it came back, the first
> cut & termination they did was good. 0.47 db of loss in that 39 klicks
> of fiber. I half expected 15 to 20 db of loss. Blew me away.  I
> probably failed but tried not to look impressed.
>
> Cheers, Gene Heskett
> --
> "There are four boxes to be used in defense of liberty:
>  soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author)
> Genes Web page 
>
> --
> Check out the vibrant tech community on one of the world's
> most engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> ___
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>
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> https://lists.sourceforge.net/lists/listinfo/emc-users


Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] Fiber optic control for CNC

[Gene Heskett]

On Sunday 23 April 2017 10:03:21 dave wrote:

> the foxcon stuff looks a bit pricey. However ...
>
> http://www.mouser.com/Toshiba/Optoelectronics/Fiber-Optics/Fiber-Optic
>-Transmitters-Receivers-Transceivers/TOSLINK/_/N-6qrgo?P=1z0zkx4Z1ybqc2
>q
>
> It actually looks affordable including cables. 10 Mb/s but that should
> handle anything linuxcnc needs. 10' simplex cables for a couple of $.
>
> https://www.monoprice.com/Product?p_id=2669=Cj0KEQjwofHHBRDS0Pnh
>pef89ucBEiQASEp6LIW3Tu9rI-YsCuV7XvPZJEDJ4M80OU09A9vYGSpppjMaAjjx8P8HAQ
>
> Dave

Only 2 transmitter modules stocked at well over a 10 dollar bill each.
No receiver modules are stocked at any price. All hat, no cattle.

That is a good enough price on ready-made cables if I wanted to do it 
with to$link.  But the above  hardware pricing is not a viable choice 
when you need lots of them. I have no intention of spending north of 
$600 for 10 fiber links.

Good info Dave, thanks.
>
> --
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> most engaging tech sites, Slashdot.org! http://sdm.link/slashdot
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Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] Fiber optic control for CNC

[Gene Heskett]

On Sunday 23 April 2017 06:47:12 Gene Heskett wrote:

> On Sunday 23 April 2017 02:03:02 Chris Albertson wrote:
> > Gene,
> > They do make such devices. But there is one fundamental difference
> > between a fiber cable and an isolator, the cable can have any length
> > and hence a WIDE range if attenuation.The cable could be short
> > and with high quality termination and low losses in the conniptions
> > of it could be very long with poorly made terminals
> >
> > So the transmitter / receiver has to be able to handle a couple
> > others of magnitude different attenuation rates.
> >
> > Look on page 2 of the below  linked document The figures describe
> > EXACTLY what you are asking for and it even compares it to an
> > isolator like you did
> > http://media.digikey/fiber-optic%20devices%20toslink.pdf
> >  >ic %20devices%20toslink.pdf>
>
> I will look when its daylight and I've got a cuppa and one eye open.
>
> Thanks.

Having arrived at a state with a cup of caffeine handy, and at least one 
eye open at the same time, I see that the toslink stuff @ $2 plus a 
connector, is rated dc to 15 megabaud, and can handle APF (all plastic 
fiber) up to 10 meters long.  That would work, at a cost per copper wire 
eliminated in the $5 to $20 range depending on the cost of toslink 
terminated cables.  And that cost rather handily takes it out of the 
picture when I can buy the non-toslink stuffs at about a buck a wire 
equ, plus the needed length of APF cable, currently UNK.  Cable that 
when the end has been prepared, is simply pushed into the 20 cent rx or 
rx terminator over the smd led or phototransistor.

> > DIgikey sells the stuff and its cheap because these parts are used
> > in consumer electronics and produced by the millions.
>
> Precisely what I am looking for.

Yes, until you throw in the royalties for using the word toslink, which 
multiplies the cost considerably.  Plus that connector is physically 
large to facilitate gripping it and plugging it in or out, something we 
would only need to do while troubleshooting.

These fibers I have in mind could probably be removed from the connector 
once it work, and given a thin coat of goop or go2 a quarter inch from 
the end, inserted back into the connector and forgotten for 20 years, 
and do it on .2" centers on the interface board. The biggest problem is 
at the rx end where a good stiff pulldown is needed to drive the opto's 
in the driver. That may require a booster transistor, depending on the 
choice of an rx ic.  Those I haven't researched extensively yet because 
I want to call a few fiber vendors tomorrow and get a price on a roll of 
size matching APF, and what the prep tool costs.  I'd love it if the 
fiber could  be directly inserted into a fiber socket in the driver, 
eliminating another translation in the drivers opto isolators.  But 
thats not going to happen until there is a market for those.  And right 
now, I'm a market sample of one. :(  If we could get a maker like 
Tormach onboard, that might be a big enough niche to fill.

[...]

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] Fiber optic control for CNC

[Ralph Stirling]

Gene,

You might find it useful look at how industrial sensors do this.  I use a lot 
of Automation Direct fiber prox sensors. They have both thru-beam and diffuse 
reflective types.  In any case, they always have lenses on the ends of the 
fibers.

https://www.automationdirect.com/adc/Shopping/Catalog/Sensors_-z-_Encoders/Fiber_Optic_Sensors/SSF_Fiber_Sensors

They have a couple of different sensor heads.  For reflective applications, I 
prefer the devices with programmable threshold and gain. Non-adjustable ones 
are ok for thru-beam.

It may be possible to use consumer optical link parts to replicate these 
sensors, but not as simple as it first appears.  The key is focusing the light 
at the fiber end.  You might try a $2 laser pointer module for the transmitter 
side to see if coherent light will reduce the need for a lens.  It may lose its 
coherence in the fiber though.

-- Ralph

On Apr 22, 2017 6:25 PM, Gene Heskett  wrote:
On Saturday 22 April 2017 20:03:05 dave wrote:

> Gene,
> I thought about the limit switch thing years ago. The problem is
> getting enough energy into a small fiber.
> 62.5 um is not a large target. However, 900 um fiber if you can find
> it might be just right. For short runs even plastic fiber should work.
>
> Dave

This stuff I'm looking at is plastic, a 1.2mm core with a 2.0mm jacket.
Plastic of course. The longest run would in the 16 feet range.

Step-dir lines to the drivers maybe 40".  At the response times I'd
expect, losses should not be that bad even in plastic.

I watched the local cable folks install a fiber link from our studio
output to the cable head end in Enterprise WV, 39 klicks long as the
cable went. This was in about 1998.  Had to send the splicer back and
get new knives or something in it, but when it came back, the first cut
& termination they did was good. 0.47 db of loss in that 39 klicks of
fiber. I half expected 15 to 20 db of loss. Blew me away.  I probably
failed but tried not to look impressed.

Cheers, Gene Heskett
--
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] Fiber optic control for CNC

[dave]

the foxcon stuff looks a bit pricey. However ...

http://www.mouser.com/Toshiba/Optoelectronics/Fiber-Optics/Fiber-Optic-Transmitters-Receivers-Transceivers/TOSLINK/_/N-6qrgo?P=1z0zkx4Z1ybqc2q

It actually looks affordable including cables. 10 Mb/s but that should 
handle anything linuxcnc needs. 10' simplex cables for a couple of $.

https://www.monoprice.com/Product?p_id=2669=Cj0KEQjwofHHBRDS0Pnhpef89ucBEiQASEp6LIW3Tu9rI-YsCuV7XvPZJEDJ4M80OU09A9vYGSpppjMaAjjx8P8HAQ

Dave

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Re: [Emc-users] Fiber optic control for CNC

[Gene Heskett]

On Sunday 23 April 2017 02:03:02 Chris Albertson wrote:

> Gene,
> They do make such devices. But there is one fundamental difference
> between a fiber cable and an isolator, the cable can have any length
> and hence a WIDE range if attenuation.The cable could be short and
> with high quality termination and low losses in the conniptions of it
> could be very long with poorly made terminals
>
> So the transmitter / receiver has to be able to handle a couple others
> of magnitude different attenuation rates.
>
> Look on page 2 of the below  linked document The figures describe
> EXACTLY what you are asking for and it even compares it to an isolator
> like you did
> http://media.digikey/fiber-optic%20devices%20toslink.pdf
> %20devices%20toslink.pdf>
>
IP will look when its daylight and I've got a cuppa and one eye open.

Thanks.

> DIgikey sells the stuff and its cheap because these parts are used in
> consumer electronics and produced by the millions.

Precisely what I am looking for.
>
> On Sat, Apr 22, 2017 at 1:01 PM, Gene Heskett  
wrote:
> > On Saturday 22 April 2017 14:26:56 Linden wrote:
> > > When I worked in the semi con industry we used to have converters
> > > for regular rs232 serial com at 9200 bod. Was a 9 pin sub d at one
> > > end of the adaptor then 2 glass fiber cables plugged in to the
> > > other. The receptacle and the fiber cable were made by omron. I
> > > think the device itself was made in Austria and grew out of some
> > > ones basement to small production. The only problems we had were
> > > the glass fiber portion of the cables not being crossed when some
> > > one had it apart or corrosion on the little PCB due to exposer to
> > > HF fumes and other nasties. This was on machines designed and
> > > built in the early 90.
> >
> > Gee I wish I could convince folks I do NOT need a serial signal at
> > such and such a baud rate. ALL I want to do is turn on an led
> > shining into the fiber at one end, and detect it with a high gain
> > phototransistor at the other end. Seems pretty simple to me.  Turn
> > on the led shining into the end of the fiber for 3 u-secs, the
> > phototransistor does a turnon at the other end, and voila! a step
> > pulse, with no noise being shoved into the circuit on either end. 
> > Leave another led turned on for the duration of the dir signal when
> > I want to reverse the direction. rs-422-485 gismos I have a bag of
> > 5, still haven't found a place to put them other than hanging on the
> > end of a usb extension cable as a pretty, lights up bright red so I
> > can pick my way out of the garage if the overhead lighting breaker
> > fails. I was going to use one to drive my vfd, till I found the fake
> > vfd didn't didn't have any seriel circuitry, not even designed in
> > but un-populated on its boards.  A SpinX1 runs it rather nicely
> > after I programmed it from its own keypad.
> >
> > > On April 22, 2017 9:56:27 AM PDT, Gene Heskett
> > > 
> >
> > wrote:
> > > >On Friday 21 April 2017 19:10:23 dave wrote:
> > > >
> > > >Did you get my PM to you yesterday evening?
> > > >
> > > >> Years ago when I thought fiber might catch-on I grabbed some
> > > >> 62.5/120 plenum fiber at Boeing Surplus.
> > > >> I got as far as connecting a 10-base2 card to a fiber converter
> > > >> fishing out both ends of the fiber on the reel
> > > >> and terminating with 3M (?) hot-melt end. It worked nicely but
> > > >> 10 Mhz isn't straining fiber very much. The good thing about
> > > >> fiber is the
> > > >
> > > >low
> > > >
> > > >> error rate; something around 1E-12. I just disposed of the
> > > >> converters a few days ago.
> > > >> Still have several Km of fiber and a few connectors. 10-baseT
> > > >> works just  fine thru conduit buried between desktop
> > > >> (house) and shop. About 35 m.
> > > >>
> > > >> Dave
> > > >
> > > >I found, at newark/element14, some  more fiber fittings, in this
> > > > case a
> > > >
> > > >board mount cover for a 603 sized smd led that the fiber can be
> > > > plugged
> > > >
> > > >into, takes 2mm od fiber, snap fit in board holes, at $0.17 a
> > > > copy from
> > > >
> > > >Bivar. Found some fiber but in 10" lengths, assembled, so still
> > > >looking.
> > > >The key brand name seems to be Bivar for the hardware. 603 size
> > > > smd leds
> > > >are similarly priced. I did find an smd phototransistor, but its
> > > > target
> > > >
> > > >is not centered in the package. Not a major problem since I'll
> > > > probably
> > > >
> > > >be designing the pcb, but it would be nice to use the same pcb
> > > > pattern on both ends.  Since Bivar has a phone numnber in the
> > > > pdf, I'll see if I
> > > >can contact them Monday.  Hopefully its still a good number.
> > > >
> > > >> On 04/21/2017 01:53 AM, Erik Christiansen wrote:
> > > >> > On 20.04.17 14:51, Gene Heskett wrote:
> > > >> >> The led makers have now had 40+ 

Re: [Emc-users] Fiber optic control for CNC

[Gene Heskett]

On Sunday 23 April 2017 01:58:32 Erik Christiansen wrote:

> On 22.04.17 21:24, Gene Heskett wrote:
> > I watched the local cable folks install a fiber link from our studio
> > output to the cable head end in Enterprise WV, 39 klicks long as the
> > cable went. This was in about 1998.  Had to send the splicer back
> > and get new knives or something in it, but when it came back, the
> > first cut & termination they did was good. 0.47 db of loss in that
> > 39 klicks of fiber. I half expected 15 to 20 db of loss. Blew me
> > away.  I probably failed but tried not to look impressed.
>
> Have to admit that I would have expected at least the same. I'm not
> sure the tech wasn't referring to the termination loss, though - that
> would be half a dB for a good termination or splice, if my wet RAM's
> refresh cycles are holding up. Back in the late 80s, when we were
> designing 565 Mb/s optical fibre transmission equipment for the Aussie
> telco, they installed a regenerator every 50 km up the coast. The
> remote power feed unit was a switchmode constant current generator
> with 300 Vdc o/c and enough oomph to power about 1000 km of
> regenerators. We called it the "Death Machine", and I was very happy
> to concentrate on the telemetry and alarm system instead, with its
> microprocessors and much more forgiving firmware.

:)

> Erik

I don't think one could get such a supply past the ULabs here.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] Fiber optic control for CNC

[Chris Albertson]

Gene,
They do make such devices. But there is one fundamental difference between
a fiber cable and an isolator, the cable can have any length and hence a
WIDE range if attenuation.The cable could be short and with high
quality termination and low losses in the conniptions of it could be very
long with poorly made terminals

So the transmitter / receiver has to be able to handle a couple others of
magnitude different attenuation rates.

Look on page 2 of the below  linked document The figures describe EXACTLY
what you are asking for and it even compares it to an isolator like you did
http://media.digikey/fiber-optic%20devices%20toslink.pdf


DIgikey sells the stuff and its cheap because these parts are used in
consumer electronics and produced by the millions.

On Sat, Apr 22, 2017 at 1:01 PM, Gene Heskett  wrote:

> On Saturday 22 April 2017 14:26:56 Linden wrote:
>
> > When I worked in the semi con industry we used to have converters for
> > regular rs232 serial com at 9200 bod. Was a 9 pin sub d at one end of
> > the adaptor then 2 glass fiber cables plugged in to the other. The
> > receptacle and the fiber cable were made by omron. I think the device
> > itself was made in Austria and grew out of some ones basement to small
> > production. The only problems we had were the glass fiber portion of
> > the cables not being crossed when some one had it apart or corrosion
> > on the little PCB due to exposer to HF fumes and other nasties. This
> > was on machines designed and built in the early 90.
> >
> Gee I wish I could convince folks I do NOT need a serial signal at such
> and such a baud rate. ALL I want to do is turn on an led shining into
> the fiber at one end, and detect it with a high gain phototransistor at
> the other end. Seems pretty simple to me.  Turn on the led shining into
> the end of the fiber for 3 u-secs, the phototransistor does a turnon at
> the other end, and voila! a step pulse, with no noise being shoved into
> the circuit on either end.  Leave another led turned on for the duration
> of the dir signal when I want to reverse the direction. rs-422-485
> gismos I have a bag of 5, still haven't found a place to put them other
> than hanging on the end of a usb extension cable as a pretty, lights up
> bright red so I can pick my way out of the garage if the overhead
> lighting breaker fails. I was going to use one to drive my vfd, till I
> found the fake vfd didn't didn't have any seriel circuitry, not even
> designed in but un-populated on its boards.  A SpinX1 runs it rather
> nicely after I programmed it from its own keypad.
>
> > On April 22, 2017 9:56:27 AM PDT, Gene Heskett 
> wrote:
> > >On Friday 21 April 2017 19:10:23 dave wrote:
> > >
> > >Did you get my PM to you yesterday evening?
> > >
> > >> Years ago when I thought fiber might catch-on I grabbed some
> > >> 62.5/120 plenum fiber at Boeing Surplus.
> > >> I got as far as connecting a 10-base2 card to a fiber converter
> > >> fishing out both ends of the fiber on the reel
> > >> and terminating with 3M (?) hot-melt end. It worked nicely but 10
> > >> Mhz isn't straining fiber very much. The good thing about fiber is
> > >> the
> > >
> > >low
> > >
> > >> error rate; something around 1E-12. I just disposed of the
> > >> converters a few days ago.
> > >> Still have several Km of fiber and a few connectors. 10-baseT works
> > >> just  fine thru conduit buried between desktop
> > >> (house) and shop. About 35 m.
> > >>
> > >> Dave
> > >
> > >I found, at newark/element14, some  more fiber fittings, in this case
> > > a
> > >
> > >board mount cover for a 603 sized smd led that the fiber can be
> > > plugged
> > >
> > >into, takes 2mm od fiber, snap fit in board holes, at $0.17 a copy
> > > from
> > >
> > >Bivar. Found some fiber but in 10" lengths, assembled, so still
> > >looking.
> > >The key brand name seems to be Bivar for the hardware. 603 size smd
> > >leds
> > >are similarly priced. I did find an smd phototransistor, but its
> > > target
> > >
> > >is not centered in the package. Not a major problem since I'll
> > > probably
> > >
> > >be designing the pcb, but it would be nice to use the same pcb
> > > pattern on both ends.  Since Bivar has a phone numnber in the pdf,
> > > I'll see if I
> > >can contact them Monday.  Hopefully its still a good number.
> > >
> > >> On 04/21/2017 01:53 AM, Erik Christiansen wrote:
> > >> > On 20.04.17 14:51, Gene Heskett wrote:
> > >> >> The led makers have now had 40+ years to design such a package,
> > >
> > >and
> > >
> > >> >> I fail to understand why it has not happened.
> > >> >
> > >> > Somewhere near the bottom of my junkbox is an envelope with a
> > >> > pair of Siemens opto-link (real product name long forgotten)
> > >> > devices, which came out around 35 years ago. They're small grey
> > >> > rectangles with through-hole pins, and a 

Re: [Emc-users] Fiber optic control for CNC

[Erik Christiansen]

On 22.04.17 21:24, Gene Heskett wrote:
> I watched the local cable folks install a fiber link from our studio 
> output to the cable head end in Enterprise WV, 39 klicks long as the 
> cable went. This was in about 1998.  Had to send the splicer back and 
> get new knives or something in it, but when it came back, the first cut 
> & termination they did was good. 0.47 db of loss in that 39 klicks of 
> fiber. I half expected 15 to 20 db of loss. Blew me away.  I probably 
> failed but tried not to look impressed.

Have to admit that I would have expected at least the same. I'm not sure
the tech wasn't referring to the termination loss, though - that would
be half a dB for a good termination or splice, if my wet RAM's refresh
cycles are holding up. Back in the late 80s, when we were designing 565
Mb/s optical fibre transmission equipment for the Aussie telco, they
installed a regenerator every 50 km up the coast. The remote power feed
unit was a switchmode constant current generator with 300 Vdc o/c and
enough oomph to power about 1000 km of regenerators. We called it the
"Death Machine", and I was very happy to concentrate on the telemetry
and alarm system instead, with its microprocessors and much more
forgiving firmware.

Erik

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Re: [Emc-users] Fiber optic control for CNC

[Gene Heskett]

On Saturday 22 April 2017 20:03:05 dave wrote:

> Gene,
> I thought about the limit switch thing years ago. The problem is
> getting enough energy into a small fiber.
> 62.5 um is not a large target. However, 900 um fiber if you can find
> it might be just right. For short runs even plastic fiber should work.
>
> Dave

This stuff I'm looking at is plastic, a 1.2mm core with a 2.0mm jacket.  
Plastic of course. The longest run would in the 16 feet range.

Step-dir lines to the drivers maybe 40".  At the response times I'd 
expect, losses should not be that bad even in plastic.

I watched the local cable folks install a fiber link from our studio 
output to the cable head end in Enterprise WV, 39 klicks long as the 
cable went. This was in about 1998.  Had to send the splicer back and 
get new knives or something in it, but when it came back, the first cut 
& termination they did was good. 0.47 db of loss in that 39 klicks of 
fiber. I half expected 15 to 20 db of loss. Blew me away.  I probably 
failed but tried not to look impressed.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] Fiber optic control for CNC

[dave]

On 04/22/2017 01:01 PM, Gene Heskett wrote:
> On Saturday 22 April 2017 14:26:56 Linden wrote:
>
>> When I worked in the semi con industry we used to have converters for
>> regular rs232 serial com at 9200 bod. Was a 9 pin sub d at one end of
>> the adaptor then 2 glass fiber cables plugged in to the other. The
>> receptacle and the fiber cable were made by omron. I think the device
>> itself was made in Austria and grew out of some ones basement to small
>> production. The only problems we had were the glass fiber portion of
>> the cables not being crossed when some one had it apart or corrosion
>> on the little PCB due to exposer to HF fumes and other nasties. This
>> was on machines designed and built in the early 90.
>>
> Gee I wish I could convince folks I do NOT need a serial signal at such
> and such a baud rate. ALL I want to do is turn on an led shining into
> the fiber at one end, and detect it with a high gain phototransistor at
> the other end. Seems pretty simple to me.  Turn on the led shining into
> the end of the fiber for 3 u-secs, the phototransistor does a turnon at
> the other end, and voila! a step pulse, with no noise being shoved into
> the circuit on either end.  Leave another led turned on for the duration
> of the dir signal when I want to reverse the direction. rs-422-485
> gismos I have a bag of 5, still haven't found a place to put them other
> than hanging on the end of a usb extension cable as a pretty, lights up
> bright red so I can pick my way out of the garage if the overhead
> lighting breaker fails. I was going to use one to drive my vfd, till I
> found the fake vfd didn't didn't have any seriel circuitry, not even
> designed in but un-populated on its boards.  A SpinX1 runs it rather
> nicely after I programmed it from its own keypad.
>
>> On April 22, 2017 9:56:27 AM PDT, Gene Heskett 
> wrote:
>>> On Friday 21 April 2017 19:10:23 dave wrote:
>>>
>>> Did you get my PM to you yesterday evening?
>>>
 Years ago when I thought fiber might catch-on I grabbed some
 62.5/120 plenum fiber at Boeing Surplus.
 I got as far as connecting a 10-base2 card to a fiber converter
 fishing out both ends of the fiber on the reel
 and terminating with 3M (?) hot-melt end. It worked nicely but 10
 Mhz isn't straining fiber very much. The good thing about fiber is
 the
>>> low
>>>
 error rate; something around 1E-12. I just disposed of the
 converters a few days ago.
 Still have several Km of fiber and a few connectors. 10-baseT works
 just  fine thru conduit buried between desktop
 (house) and shop. About 35 m.

 Dave
>>> I found, at newark/element14, some  more fiber fittings, in this case
>>> a
>>>
>>> board mount cover for a 603 sized smd led that the fiber can be
>>> plugged
>>>
>>> into, takes 2mm od fiber, snap fit in board holes, at $0.17 a copy
>>> from
>>>
>>> Bivar. Found some fiber but in 10" lengths, assembled, so still
>>> looking.
>>> The key brand name seems to be Bivar for the hardware. 603 size smd
>>> leds
>>> are similarly priced. I did find an smd phototransistor, but its
>>> target
>>>
>>> is not centered in the package. Not a major problem since I'll
>>> probably
>>>
>>> be designing the pcb, but it would be nice to use the same pcb
>>> pattern on both ends.  Since Bivar has a phone numnber in the pdf,
>>> I'll see if I
>>> can contact them Monday.  Hopefully its still a good number.
>>>
 On 04/21/2017 01:53 AM, Erik Christiansen wrote:
> On 20.04.17 14:51, Gene Heskett wrote:
>> The led makers have now had 40+ years to design such a package,
>>> and
>>>
>> I fail to understand why it has not happened.
> Somewhere near the bottom of my junkbox is an envelope with a
> pair of Siemens opto-link (real product name long forgotten)
> devices, which came out around 35 years ago. They're small grey
> rectangles with through-hole pins, and a fibre entry with
> ring-nut (like on a collet holder) on one end. Dunno if they're
> still marketed, though.
>
> At Digi-key, this Broadcom offering looks just like one end:
>>> https://www.digikey.com/product-detail/en/broadcom-limited/SP638
>>>
> 58/516-2872-ND/2220931
>
> But that would leave the rest of my coil of shielded twisted-pair
> (for RS485) cable gathering dust. With 7v of permissible
> common-mode, and differential transmission for noise immunity,
> what more is really needed? RS485 transceivers are around $2 to
> $3 IIRC. (I saw some for 25c today, but they were surplus stock
> of a now obsolete device.)
>
> Erik
>>> -
>>> -
>>>
>>>
Gene,
I thought about the limit switch thing years ago. The problem is getting 
enough energy into a small fiber.
62.5 um is not a large target. However, 900 um fiber if you can find it 
might be just right. For short runs even plastic fiber should work.

Re: [Emc-users] Fiber optic control for CNC

[Gregg Eshelman]

In other words you just need long distance opto-isolators.

On Saturday, April 22, 2017, 2:06:53 PM MDT, Gene Heskett 
 wrote:
Gee I wish I could convince folks I do NOT need a serial signal at such 
and such a baud rate. ALL I want to do is turn on an led shining into 
the fiber at one end, and detect it with a high gain phototransistor at 
the other end. Seems pretty simple to me.  Turn on the led shining into 
the end of the fiber for 3 u-secs, the phototransistor does a turnon at 
the other end, and voila! a step pulse, with no noise being shoved into 
the circuit on either end.  Leave another led turned on for the duration 
of the dir signal when I want to reverse the direction. rs-422-485 
gismos I have a bag of 5, still haven't found a place to put them other 
than hanging on the end of a usb extension cable as a pretty, lights up 
bright red so I can pick my way out of the garage if the overhead 
lighting breaker fails. I was going to use one to drive my vfd, till I 
found the fake vfd didn't didn't have any seriel circuitry, not even 
designed in but un-populated on its boards.  A SpinX1 runs it rather 
nicely after I programmed it from its own keypad.
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Re: [Emc-users] Fiber optic control for CNC

[Gregg Eshelman]

Probably. A google for fiber optic USB shows the thing exists.

On Saturday, April 22, 2017, 1:46:56 PM MDT, Roland Jollivet 
 wrote:Maybe not for CNC, but would USB-fibre -- 
fibre-USB cables transcend the
terrible 5m limit?

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Re: [Emc-users] Fiber optic control for CNC

[Gene Heskett]

On Saturday 22 April 2017 14:26:56 Linden wrote:

> When I worked in the semi con industry we used to have converters for
> regular rs232 serial com at 9200 bod. Was a 9 pin sub d at one end of
> the adaptor then 2 glass fiber cables plugged in to the other. The
> receptacle and the fiber cable were made by omron. I think the device
> itself was made in Austria and grew out of some ones basement to small
> production. The only problems we had were the glass fiber portion of
> the cables not being crossed when some one had it apart or corrosion
> on the little PCB due to exposer to HF fumes and other nasties. This
> was on machines designed and built in the early 90.
>
Gee I wish I could convince folks I do NOT need a serial signal at such 
and such a baud rate. ALL I want to do is turn on an led shining into 
the fiber at one end, and detect it with a high gain phototransistor at 
the other end. Seems pretty simple to me.  Turn on the led shining into 
the end of the fiber for 3 u-secs, the phototransistor does a turnon at 
the other end, and voila! a step pulse, with no noise being shoved into 
the circuit on either end.  Leave another led turned on for the duration 
of the dir signal when I want to reverse the direction. rs-422-485 
gismos I have a bag of 5, still haven't found a place to put them other 
than hanging on the end of a usb extension cable as a pretty, lights up 
bright red so I can pick my way out of the garage if the overhead 
lighting breaker fails. I was going to use one to drive my vfd, till I 
found the fake vfd didn't didn't have any seriel circuitry, not even 
designed in but un-populated on its boards.  A SpinX1 runs it rather 
nicely after I programmed it from its own keypad.   

> On April 22, 2017 9:56:27 AM PDT, Gene Heskett  
wrote:
> >On Friday 21 April 2017 19:10:23 dave wrote:
> >
> >Did you get my PM to you yesterday evening?
> >
> >> Years ago when I thought fiber might catch-on I grabbed some
> >> 62.5/120 plenum fiber at Boeing Surplus.
> >> I got as far as connecting a 10-base2 card to a fiber converter
> >> fishing out both ends of the fiber on the reel
> >> and terminating with 3M (?) hot-melt end. It worked nicely but 10
> >> Mhz isn't straining fiber very much. The good thing about fiber is
> >> the
> >
> >low
> >
> >> error rate; something around 1E-12. I just disposed of the
> >> converters a few days ago.
> >> Still have several Km of fiber and a few connectors. 10-baseT works
> >> just  fine thru conduit buried between desktop
> >> (house) and shop. About 35 m.
> >>
> >> Dave
> >
> >I found, at newark/element14, some  more fiber fittings, in this case
> > a
> >
> >board mount cover for a 603 sized smd led that the fiber can be
> > plugged
> >
> >into, takes 2mm od fiber, snap fit in board holes, at $0.17 a copy
> > from
> >
> >Bivar. Found some fiber but in 10" lengths, assembled, so still
> >looking.
> >The key brand name seems to be Bivar for the hardware. 603 size smd
> >leds
> >are similarly priced. I did find an smd phototransistor, but its
> > target
> >
> >is not centered in the package. Not a major problem since I'll
> > probably
> >
> >be designing the pcb, but it would be nice to use the same pcb
> > pattern on both ends.  Since Bivar has a phone numnber in the pdf,
> > I'll see if I
> >can contact them Monday.  Hopefully its still a good number.
> >
> >> On 04/21/2017 01:53 AM, Erik Christiansen wrote:
> >> > On 20.04.17 14:51, Gene Heskett wrote:
> >> >> The led makers have now had 40+ years to design such a package,
> >
> >and
> >
> >> >> I fail to understand why it has not happened.
> >> >
> >> > Somewhere near the bottom of my junkbox is an envelope with a
> >> > pair of Siemens opto-link (real product name long forgotten)
> >> > devices, which came out around 35 years ago. They're small grey
> >> > rectangles with through-hole pins, and a fibre entry with
> >> > ring-nut (like on a collet holder) on one end. Dunno if they're
> >> > still marketed, though.
> >> >
> >> > At Digi-key, this Broadcom offering looks just like one end:
> >
> >https://www.digikey.com/product-detail/en/broadcom-limited/SP638
> >
> >> >58/516-2872-ND/2220931
> >> >
> >> > But that would leave the rest of my coil of shielded twisted-pair
> >> > (for RS485) cable gathering dust. With 7v of permissible
> >> > common-mode, and differential transmission for noise immunity,
> >> > what more is really needed? RS485 transceivers are around $2 to
> >> > $3 IIRC. (I saw some for 25c today, but they were surplus stock
> >> > of a now obsolete device.)
> >> >
> >> > Erik
> >
> >
> >
> >> >-- Check out the vibrant tech community on one of the
> >
> >world's
> >
> >> > most engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> >> > ___
> >> > Emc-users mailing list
> >> > Emc-users@lists.sourceforge.net
> >> > 

Re: [Emc-users] Fiber optic control for CNC

[Linden]

When I worked in the semi con industry we used to have converters for regular 
rs232 serial com at 9200 bod. Was a 9 pin sub d at one end of the adaptor then 
2 glass fiber cables plugged in to the other. The receptacle and the fiber 
cable were made by omron. I think the device itself was made in Austria and 
grew out of some ones basement to small production. The only problems we had 
were the glass fiber portion of the cables not being crossed when some one had 
it apart or corrosion on the little PCB due to exposer to HF fumes and other 
nasties. This was on machines designed and built in the early 90.

On April 22, 2017 9:56:27 AM PDT, Gene Heskett  wrote:
>On Friday 21 April 2017 19:10:23 dave wrote:
>
>Did you get my PM to you yesterday evening?
>
>> Years ago when I thought fiber might catch-on I grabbed some 62.5/120
>> plenum fiber at Boeing Surplus.
>> I got as far as connecting a 10-base2 card to a fiber converter
>> fishing out both ends of the fiber on the reel
>> and terminating with 3M (?) hot-melt end. It worked nicely but 10 Mhz
>> isn't straining fiber very much. The good thing about fiber is the
>low
>> error rate; something around 1E-12. I just disposed of the converters
>> a few days ago.
>> Still have several Km of fiber and a few connectors. 10-baseT works
>> just  fine thru conduit buried between desktop
>> (house) and shop. About 35 m.
>>
>> Dave
>
>I found, at newark/element14, some  more fiber fittings, in this case a
>
>board mount cover for a 603 sized smd led that the fiber can be plugged
>
>into, takes 2mm od fiber, snap fit in board holes, at $0.17 a copy from
>
>Bivar. Found some fiber but in 10" lengths, assembled, so still
>looking.  
>The key brand name seems to be Bivar for the hardware. 603 size smd
>leds 
>are similarly priced. I did find an smd phototransistor, but its target
>
>is not centered in the package. Not a major problem since I'll probably
>
>be designing the pcb, but it would be nice to use the same pcb pattern 
>on both ends.  Since Bivar has a phone numnber in the pdf, I'll see if
>I 
>can contact them Monday.  Hopefully its still a good number.
>
>> On 04/21/2017 01:53 AM, Erik Christiansen wrote:
>> > On 20.04.17 14:51, Gene Heskett wrote:
>> >> The led makers have now had 40+ years to design such a package,
>and
>> >> I fail to understand why it has not happened.
>> >
>> > Somewhere near the bottom of my junkbox is an envelope with a pair
>> > of Siemens opto-link (real product name long forgotten) devices,
>> > which came out around 35 years ago. They're small grey rectangles
>> > with through-hole pins, and a fibre entry with ring-nut (like on a
>> > collet holder) on one end. Dunno if they're still marketed, though.
>> >
>> > At Digi-key, this Broadcom offering looks just like one end:
>> >
>> >
>https://www.digikey.com/product-detail/en/broadcom-limited/SP638
>> >58/516-2872-ND/2220931
>> >
>> > But that would leave the rest of my coil of shielded twisted-pair
>> > (for RS485) cable gathering dust. With 7v of permissible
>> > common-mode, and differential transmission for noise immunity, what
>> > more is really needed? RS485 transceivers are around $2 to $3 IIRC.
>> > (I saw some for 25c today, but they were surplus stock of a now
>> > obsolete device.)
>> >
>> > Erik
>> >
>> >
>
>> >-- Check out the vibrant tech community on one of the
>world's
>> > most engaging tech sites, Slashdot.org! http://sdm.link/slashdot
>> > ___
>> > Emc-users mailing list
>> > Emc-users@lists.sourceforge.net
>> > https://lists.sourceforge.net/lists/listinfo/emc-users
>>
>>
>--
>> Check out the vibrant tech community on one of the world's
>> most engaging tech sites, Slashdot.org! http://sdm.link/slashdot
>> ___
>> Emc-users mailing list
>> Emc-users@lists.sourceforge.net
>> https://lists.sourceforge.net/lists/listinfo/emc-users
>
>
>Cheers, Gene Heskett
>-- 
>"There are four boxes to be used in defense of liberty:
> soap, ballot, jury, and ammo. Please use in that order."
>-Ed Howdershelt (Author)
>Genes Web page 
>
>--
>Check out the vibrant tech community on one of the world's most
>engaging tech sites, Slashdot.org! http://sdm.link/slashdot
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>https://lists.sourceforge.net/lists/listinfo/emc-users

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Re: [Emc-users] Fiber optic control for CNC

[Gene Heskett]

On Friday 21 April 2017 19:10:23 dave wrote:

Did you get my PM to you yesterday evening?

> Years ago when I thought fiber might catch-on I grabbed some 62.5/120
> plenum fiber at Boeing Surplus.
> I got as far as connecting a 10-base2 card to a fiber converter
> fishing out both ends of the fiber on the reel
> and terminating with 3M (?) hot-melt end. It worked nicely but 10 Mhz
> isn't straining fiber very much. The good thing about fiber is the low
> error rate; something around 1E-12. I just disposed of the converters
> a few days ago.
> Still have several Km of fiber and a few connectors. 10-baseT works
> just  fine thru conduit buried between desktop
> (house) and shop. About 35 m.
>
> Dave

I found, at newark/element14, some  more fiber fittings, in this case a 
board mount cover for a 603 sized smd led that the fiber can be plugged 
into, takes 2mm od fiber, snap fit in board holes, at $0.17 a copy from 
Bivar. Found some fiber but in 10" lengths, assembled, so still looking.  
The key brand name seems to be Bivar for the hardware. 603 size smd leds 
are similarly priced. I did find an smd phototransistor, but its target 
is not centered in the package. Not a major problem since I'll probably 
be designing the pcb, but it would be nice to use the same pcb pattern 
on both ends.  Since Bivar has a phone numnber in the pdf, I'll see if I 
can contact them Monday.  Hopefully its still a good number.

> On 04/21/2017 01:53 AM, Erik Christiansen wrote:
> > On 20.04.17 14:51, Gene Heskett wrote:
> >> The led makers have now had 40+ years to design such a package, and
> >> I fail to understand why it has not happened.
> >
> > Somewhere near the bottom of my junkbox is an envelope with a pair
> > of Siemens opto-link (real product name long forgotten) devices,
> > which came out around 35 years ago. They're small grey rectangles
> > with through-hole pins, and a fibre entry with ring-nut (like on a
> > collet holder) on one end. Dunno if they're still marketed, though.
> >
> > At Digi-key, this Broadcom offering looks just like one end:
> >
> > https://www.digikey.com/product-detail/en/broadcom-limited/SP638
> >58/516-2872-ND/2220931
> >
> > But that would leave the rest of my coil of shielded twisted-pair
> > (for RS485) cable gathering dust. With 7v of permissible
> > common-mode, and differential transmission for noise immunity, what
> > more is really needed? RS485 transceivers are around $2 to $3 IIRC.
> > (I saw some for 25c today, but they were surplus stock of a now
> > obsolete device.)
> >
> > Erik
> >
> > 
> >-- Check out the vibrant tech community on one of the world's
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 soap, ballot, jury, and ammo. Please use in that order."
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Re: [Emc-users] Fiber optic control for CNC

[Gregg Eshelman]

Fiber was 200 megabit, 100 each way. Had to have two fibers for full speed. 
Then came 100 megabit full duplex wired Ethernet, matching the speed of fiber. 
For some reason companies quit working on fiber to speed it up as an 
alternative to Ethernet.
Then came gigabit, 2.5 gigabit, 5 and now 10 gigabit on copper. 5 gigabit can 
make a NAS pretty much as good as a locally connected SATA drive.

Fiber 'cables' can often be found dirt cheap, pieces ready to plug in. But try 
finding the network cards. Then what about drivers for anything newer than 
Windows XP?
Fiber for local computer networking has died due to apathy and neglect, 
surpassed by even the lowliest DSL connection over POTS for long distance links 
- which most of the time now get switched over fiber optic lines.

On Friday, April 21, 2017, 5:16:49 PM MDT, dave  
wrote:Years ago when I thought fiber might catch-on I grabbed some 62.5/120 
plenum fiber at Boeing Surplus.
I got as far as connecting a 10-base2 card to a fiber converter fishing 
out both ends of the fiber on the reel
and terminating with 3M (?) hot-melt end. It worked nicely but 10 Mhz 
isn't straining fiber very much. The good thing about fiber is the low 
error rate; something around 1E-12. I just disposed of the converters a 
few days ago.
Still have several Km of fiber and a few connectors. 10-baseT works 
just  fine thru conduit buried between desktop
(house) and shop. About 35 m.
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Re: [Emc-users] Fiber optic control for CNC

[dave]

Years ago when I thought fiber might catch-on I grabbed some 62.5/120 
plenum fiber at Boeing Surplus.
I got as far as connecting a 10-base2 card to a fiber converter fishing 
out both ends of the fiber on the reel
and terminating with 3M (?) hot-melt end. It worked nicely but 10 Mhz 
isn't straining fiber very much. The good thing about fiber is the low 
error rate; something around 1E-12. I just disposed of the converters a 
few days ago.
Still have several Km of fiber and a few connectors. 10-baseT works 
just  fine thru conduit buried between desktop
(house) and shop. About 35 m.

Dave

On 04/21/2017 01:53 AM, Erik Christiansen wrote:
> On 20.04.17 14:51, Gene Heskett wrote:
>> The led makers have now had 40+ years to design such a package, and I
>> fail to understand why it has not happened.
> Somewhere near the bottom of my junkbox is an envelope with a pair of
> Siemens opto-link (real product name long forgotten) devices, which came
> out around 35 years ago. They're small grey rectangles with through-hole
> pins, and a fibre entry with ring-nut (like on a collet holder) on one
> end. Dunno if they're still marketed, though.
>
> At Digi-key, this Broadcom offering looks just like one end:
>
> https://www.digikey.com/product-detail/en/broadcom-limited/SP63858/516-2872-ND/2220931
>
> But that would leave the rest of my coil of shielded twisted-pair (for
> RS485) cable gathering dust. With 7v of permissible common-mode, and
> differential transmission for noise immunity, what more is really
> needed? RS485 transceivers are around $2 to $3 IIRC. (I saw some for 25c
> today, but they were surplus stock of a now obsolete device.)
>
> Erik
>
> --
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Re: [Emc-users] Fiber optic control for CNC

[Chris Albertson]

On Thu, Apr 20, 2017 at 8:54 PM, Danny Miller  wrote:
> Leadshine drives input/output are not just opto, they're differential.
> i.e. the step signal has 2 wires and dir has 2 wires,

You are right the noise impunity could be VERY good.  But I bet 99% of
users simply tie one end to ground and send single ended pluses.   (
But I'd say you don't get to complain about noise if you do this.)

> Fiber optic requires serialization, added a lot of new complexity and
> latency, for no real benefit.

Two comments on that
(1) One COULD use a bundle for fibers just like they use a bundle of
wires.  Replace each wire with one fiber.   It is not that horribly
expensive.   But why bother?

(2) Serialization is not hard and is already done for you if your Mesa
FPGA card is the Ethernet type.  Simply use a fiber Ethernet link.

(3) Benefit, I agree.  Fiber only makes sense in an application where
even shielded twisted pairs can't work. Or if you need isolation from
lightening strikes


-- 

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Redondo Beach, California

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Re: [Emc-users] Fiber optic control for CNC

[Erik Christiansen]

On 21.04.17 06:57, Gene Heskett wrote:
> On Friday 21 April 2017 04:53:14 Erik Christiansen wrote:
> > At Digi-key, this Broadcom offering looks just like one end:
> >
> > https://www.digikey.com/product-detail/en/broadcom-limited/SP63858
> >/516-2872-ND/2220931
> >
> Neat. North of $12?  No way Jose'. What I am looking at is $2.35 a copy 
> for the transmitter, and the receiver is $2.00/copy.  What seems to be 
> missing is the interconnection fiber.  Dennis is still looking for that.

Yeah, that's way too expensive. The fibre which came with my two samples
was just a thick plastic fibre - same quality as the stuff used for
fibre optic lamps at the time, I figure.

Here in Oz there are people using POF for ethernet, and patch cords seem
to be a stock item:

http://www.afwtechnologies.com.au/plastic_fiber.html

The prices here are more manageable if you ignore the terminated cable,
and go for bare:

http://au.element14.com/fiber-optic-cable

However, I'd expect the stuff used for low tech purposes to be cheaper:

http://www.opticfibrelighting.com.au/category_oflfibrecable

And when the needed range isn't likely to exceed 3 metres, and the
end-emitting stuff seems to be jacketed (giving mechanical protection),
then I suspect it might be the most economical choice. The 2.5 mm
diameter stuff would plug straight into the Tx/Rx units, if my memory of
their size is right.

There must be more sources up there where it snows, than down here - we
import the stuff, I'm certain. 

Erik



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Re: [Emc-users] Fiber optic control for CNC

[Gene Heskett]

On Friday 21 April 2017 04:53:14 Erik Christiansen wrote:

> On 20.04.17 14:51, Gene Heskett wrote:
> > The led makers have now had 40+ years to design such a package, and
> > I fail to understand why it has not happened.
>
> Somewhere near the bottom of my junkbox is an envelope with a pair of
> Siemens opto-link (real product name long forgotten) devices, which
> came out around 35 years ago. They're small grey rectangles with
> through-hole pins, and a fibre entry with ring-nut (like on a collet
> holder) on one end. Dunno if they're still marketed, though.
>
> At Digi-key, this Broadcom offering looks just like one end:
>
> https://www.digikey.com/product-detail/en/broadcom-limited/SP63858
>/516-2872-ND/2220931
>
Neat. North of $12?  No way Jose'. What I am looking at is $2.35 a copy 
for the transmitter, and the receiver is $2.00/copy.  What seems to be 
missing is the interconnection fiber.  Dennis is still looking for that.

> But that would leave the rest of my coil of shielded twisted-pair (for
> RS485) cable gathering dust. With 7v of permissible common-mode, and
> differential transmission for noise immunity, what more is really
> needed? RS485 transceivers are around $2 to $3 IIRC. (I saw some for
> 25c today, but they were surplus stock of a now obsolete device.)
>
> Erik
>
> --
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> most engaging tech sites, Slashdot.org! http://sdm.link/slashdot
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Cheers, Gene Heskett
-- 
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 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] Fiber optic control for CNC

[Gene Heskett]

On Thursday 20 April 2017 23:54:53 Danny Miller wrote:

> Leadshine drives input/output are not just opto, they're differential.
> i.e. the step signal has 2 wires and dir has 2 wires, there's no
> common ground or common anode.  So they're not just galvoisolated from
> the pulse source, but from each other.
>
> When run as twisted pairs or just pairs, the noise immunity is greater
> than you'd ever need.
>
> You are still going to tie them together as common-gnd or common-anode
> at the pulse source, but the differential-pair part that creates is
> important.

You are saying in essence that I should be powering the drivers opto's as 
two twisted pairs, + from the 5 volt source on the 7i90, and - from the 
gpio pin. Nice in theory I suppose, but prevented by the fact that the 
7i90 has a total of 4, 5 volt srcs, one pin on each of the 3 50 pin 
connectors and the 5 volt power src. The ability to handle large numbers 
of 5 volt srcs is handled by an inch of bare 14 gauge wire inserted into 
the back of that teeny power connector, and the various grounds and 5 
volt loads such as the + connectors on the drives are soldered on there.
Grounds can be had as there is a ground pin on the other row of the 50 
pin for every active input or output.

Radiated noise inside the box those 2 drivers are in can be picked up 
with nothing but the push-on clip it to a wire clip of the typical 10x 
probe feeding a gigahertz sampler scope, spectrum of that noise seems 
peaked at 90 to 110 mhz, and can easily exceed 30 volts peak to peak in 
the air 2" from the drivers. With only a 5 volt tolerance at the 
connections on the 7i90, I've destroyed 3 of the 7i90's so far.

I see that going to fiber as a way to prevent the nominally 12" piece of 
ribbon cable going to the drivers input opto's as an antenna, 
potentially destroying yet another 7i90. I have just received a separate 
box, way bigger than needed, which I am going to move the pi, the 7i90, 
and a large group of snubber diodes so that no input can go above about 
4.75 volts, nor below ground more than the on bias of a 1n914, and 
bypassed to ground with a .005 ceramic capacitor. Each i/o line will be 
so protected.

The way the spi cable leaves the pi and connects to the 7i90 is problem 
because just about the only way to run it that doesn't need a pin order 
swap, is to run it over the pi, or under it. Running the pi on 1" high 
standoff, it can run under the pi and be about 2" shorter than my 
present lashup, which has to improve the noise margin of the spi bus.

That leaves room for the hdmi cable to clear the 7i90 sitting on much 
lower standoffs.  And thats a ground loop right there because the 
monitor has its own power cord ground, so thats a good noise pickup src.

> Fiber optic requires serialization, added a lot of new complexity and
> latency, for no real benefit.

Serialization?  How so?  Maybe with toslink. Here the led is on, or its 
off. Signal latencies are  nanoseconds in single digit quantities.  This 
is not, and never will be, an encoded serial bit stream anyplace but 
over the spi cable. Anything else is a logic signal of totally arbitrary 
duration.  With enough noise on it to destroy a 7i90. BTDT, 3 too many 
times already.

And I've just clicked on a bigger box to put the power electronics in, so 
I will be able to put the vfd inside it. And I'd really like to make ALL 
of those control interconnects fiber.  Presently thats 4 to drive the 
steppers, 3 to drive the SpinX1, and two to drive a pair of SSR's 
switching all motor power with the LCNC enable button. 9 total. With the 
links I sent earlier, the only missing piece is the fiber 
interconnection, which is not a toslink style connector & therefore 1/4 
the cost since there shouldn't be a toslink/firewire royalty to pay per 
socket. Apparently those royalties are still being collected despite 
Jack Tramiel's passing some years ago.

> Danny

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] Fiber optic control for CNC

[Erik Christiansen]

On 20.04.17 14:51, Gene Heskett wrote:
> The led makers have now had 40+ years to design such a package, and I 
> fail to understand why it has not happened.

Somewhere near the bottom of my junkbox is an envelope with a pair of
Siemens opto-link (real product name long forgotten) devices, which came
out around 35 years ago. They're small grey rectangles with through-hole
pins, and a fibre entry with ring-nut (like on a collet holder) on one
end. Dunno if they're still marketed, though.

At Digi-key, this Broadcom offering looks just like one end:

https://www.digikey.com/product-detail/en/broadcom-limited/SP63858/516-2872-ND/2220931

But that would leave the rest of my coil of shielded twisted-pair (for
RS485) cable gathering dust. With 7v of permissible common-mode, and
differential transmission for noise immunity, what more is really
needed? RS485 transceivers are around $2 to $3 IIRC. (I saw some for 25c
today, but they were surplus stock of a now obsolete device.)

Erik

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Re: [Emc-users] Fiber optic control for CNC

[Gregg Eshelman]

Such exists. It's called TOSLINK. It's used for digital audio but should be 
adaptable to other sorts of digital optical communication.

On Thursday, April 20, 2017, 12:58:32 PM MDT, Gene Heskett 
 wrote:On Thursday 20 April 2017 11:22:03 Todd Zuercher 
wrote:

> Fanuc has been using fiber optic connections for more than 30 years. 
> And I work with an old SCM machine with a Num 1040 control that has a
> bank of fiber optic remote io that is one of the things holding me
> back from trying to convert it to Linuxcnc.
>
This has been a wish of mine for a long time.  We need some cheap stuff 
that can be the equ of an opto-isolator, but with a piece of glass or 
plastic fiber up to several feet long as the optical media between them. 
With power on the rx end, signal losses in the plastic fiber could be 
easily compensated. I can visualize stepper drivers incorporating it, 
probably at no more cost for the pair of fiber sockets than they cost 
for the full opto-isolation BOM right now.

All we would need would be an HE IR LED with a molded in funnel to guide 
the fiber tip to the chip face in the LED.  Some sort of a jacket on the 
fiber to prolong its life if rubbing on something, or to prevent optical 
crosstalk would be needed. The major design problem AISI is in gripping 
the fiber to anchor it at both ends, with long term gripping pressure 
imprinting itself on the fiber creating radiation leaks.  Even glass 
will do that, but usually over time frames that exceed the life of the 
rest of the machine since technically, glass is a super-cooled liquid, 
flowing visibly over the lifetime of the observer.

The led makers have now had 40+ years to design such a package, and I 
fail to understand why it has not happened.

Or has it, and I missed the announcement?  Thats a plausible excuse given 
my age and retired status. If anybody would have it on this side of the 
pond, digikey, and I've only found one candidate so far. Intended to be 
a remoteable indicator, the led is conventional shaped, available in 
several colors.  Pricing starts at $2.15 with a 6" light pipe, Available 
up to 3940" long. :) With the far end of that pipe facing into an 
avalanche mode transistor, mounted exactly the same as the led, and 
substituted for the BOM that puts the opto-isolation into the stepper 
drivers input circuits, it ought to be essentially free! What sort of 
speed would have TBD.  But I'd certainly have to think its faster than 
the 200 to 300 kilohertz we can now drive a $35 M542 stepper driver.

Look at 

And see what you think of it.

One of those in red led, looking at one of these:



Would I think, be a good test bed. Need some smd bypassing of the rx 
supply, and I'm not sure what buffering might be needed to make it 
actually drive the opto's in the stepper driver.  Pulse time distortions 
are quite small and the data rate can be as high as 16 megabaud.

Now if I can find where to source the fiber cable it uses in say 10' 
pieces, I could try it out in this lathe conversion. With 10 40" 
assemblies, I could put feet and sheet metal between the pi-7i90 and the 
noise makers already installed.  With 30 of them I could replace the 
copper leaving the pi's box, except for the power cord, with fiber, and 
enjoy the peace and quiet.

And I've got Dennis Strander at DigiKey furiously sending out requests 
for more info. W/O the fibers, we're under a $5 bill a connection so 
far. I can live with that.  We'll see what falls out of my email box in 
the next few hours.

> - Original Message -
> From: "Gregg Eshelman" 
> To: "Enhanced Machine Controller (EMC)"
>  Sent: Thursday, April 20, 2017
> 4:39:08 AM
> Subject: [Emc-users] Fiber optic control for CNC
>
> Looks interesting. Can't have a ground loop when there's no wires.
> http://hackaday.com/2016/03/20/add-fiber-optic-control-to-your-cnc/
>
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 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

Re: [Emc-users] Fiber optic control for CNC

[Danny Miller]

Leadshine drives input/output are not just opto, they're differential.  
i.e. the step signal has 2 wires and dir has 2 wires, there's no common 
ground or common anode.  So they're not just galvoisolated from the 
pulse source, but from each other.

When run as twisted pairs or just pairs, the noise immunity is greater 
than you'd ever need.

You are still going to tie them together as common-gnd or common-anode 
at the pulse source, but the differential-pair part that creates is 
important.

Fiber optic requires serialization, added a lot of new complexity and 
latency, for no real benefit.

Danny


On 4/20/2017 3:10 PM, Chris Albertson wrote:
> Yes.  The linked device acts just like 1/2 of a 3.3 volt opto isolator.
>
> However there are devices LIKE it that cost 1/10 as much, run on 5
> volts are faster and use consumer grade cables.
>
> But the ability to use un-terminated fiber cable cut from a bulk
> spool.  It is worth paying more for that.
>
> I'm wondering WHY?  Is it for galvanic isolation?  A small opto device
> does that.  Is it for noise impunity, shielded differential twisted
> pair cable does that really well.  Normal 100BaseT  Ethernet is
> already differential and isolated.  The normal engineering method is
> to first spec a requirement THEN look for parts.  This saves a lot of
> work compared to doing it the other way around.
>
>
>
>
> On Thu, Apr 20, 2017 at 12:22 PM, Ken Strauss <ken.stra...@sympatico.ca> 
> wrote:
>> Could something like
>> https://www.digikey.com/catalog/en/partgroup/afbr-1528cz/66628 be useful?
>> They are about $12 each but operate at 5Mbps so perhaps you could multiplex
>> some of the signals. There is also an eval kit
>> https://www.digikey.com/products/en/development-boards-kits-programmers/eval
>> uation-and-demonstration-boards-and-kits/787?k=hfbr-1506amz  You can get
>> 10-foot fibre patch cables with SMA terminations to avoid making your own.
>>
>>> -Original Message-
>>> From: Gene Heskett [mailto:ghesk...@shentel.net]
>>> Sent: Thursday, April 20, 2017 2:51 PM
>>> To: emc-users@lists.sourceforge.net
>>> Subject: Re: [Emc-users] Fiber optic control for CNC
>>>
>>> On Thursday 20 April 2017 11:22:03 Todd Zuercher wrote:
>>>
>>>> Fanuc has been using fiber optic connections for more than 30 years.
>>>> And I work with an old SCM machine with a Num 1040 control that has a
>>>> bank of fiber optic remote io that is one of the things holding me
>>>> back from trying to convert it to Linuxcnc.
>>>>
>>> This has been a wish of mine for a long time.  We need some cheap stuff
>> that
>>> can be the equ of an opto-isolator, but with a piece of glass or plastic
>> fiber up
>>> to several feet long as the optical media between them.
>>> With power on the rx end, signal losses in the plastic fiber could be
>> easily
>>> compensated. I can visualize stepper drivers incorporating it, probably at
>> no
>>> more cost for the pair of fiber sockets than they cost for the full opto-
>>> isolation BOM right now.
>>>
>>> All we would need would be an HE IR LED with a molded in funnel to guide
>> the
>>> fiber tip to the chip face in the LED.  Some sort of a jacket on the fiber
>> to
>>> prolong its life if rubbing on something, or to prevent optical crosstalk
>> would
>>> be needed. The major design problem AISI is in gripping the fiber to
>> anchor it
>>> at both ends, with long term gripping pressure imprinting itself on the
>> fiber
>>> creating radiation leaks.  Even glass will do that, but usually over time
>> frames
>>> that exceed the life of the rest of the machine since technically, glass
>> is a
>>> super-cooled liquid, flowing visibly over the lifetime of the observer.
>>>
>>> The led makers have now had 40+ years to design such a package, and I fail
>> to
>>> understand why it has not happened.
>>>
>>> Or has it, and I missed the announcement?  Thats a plausible excuse given
>> my
>>> age and retired status. If anybody would have it on this side of the pond,
>>> digikey, and I've only found one candidate so far. Intended to be a
>> remoteable
>>> indicator, the led is conventional shaped, available in several colors.
>> Pricing
>>> starts at $2.15 with a 6" light pipe, Available up to 3940" long. :) With
>> the far
>>> end of that pipe facing into an avalanche mode transistor, mounted exactly
>>> the same as the led, and substituted for the BOM that puts the
>> opto-is

Re: [Emc-users] Fiber optic control for CNC

[Chris Albertson]

Yes.  The linked device acts just like 1/2 of a 3.3 volt opto isolator.

However there are devices LIKE it that cost 1/10 as much, run on 5
volts are faster and use consumer grade cables.

But the ability to use un-terminated fiber cable cut from a bulk
spool.  It is worth paying more for that.

I'm wondering WHY?  Is it for galvanic isolation?  A small opto device
does that.  Is it for noise impunity, shielded differential twisted
pair cable does that really well.  Normal 100BaseT  Ethernet is
already differential and isolated.  The normal engineering method is
to first spec a requirement THEN look for parts.  This saves a lot of
work compared to doing it the other way around.




On Thu, Apr 20, 2017 at 12:22 PM, Ken Strauss <ken.stra...@sympatico.ca> wrote:
> Could something like
> https://www.digikey.com/catalog/en/partgroup/afbr-1528cz/66628 be useful?
> They are about $12 each but operate at 5Mbps so perhaps you could multiplex
> some of the signals. There is also an eval kit
> https://www.digikey.com/products/en/development-boards-kits-programmers/eval
> uation-and-demonstration-boards-and-kits/787?k=hfbr-1506amz  You can get
> 10-foot fibre patch cables with SMA terminations to avoid making your own.
>
>> -Original Message-
>> From: Gene Heskett [mailto:ghesk...@shentel.net]
>> Sent: Thursday, April 20, 2017 2:51 PM
>> To: emc-users@lists.sourceforge.net
>> Subject: Re: [Emc-users] Fiber optic control for CNC
>>
>> On Thursday 20 April 2017 11:22:03 Todd Zuercher wrote:
>>
>> > Fanuc has been using fiber optic connections for more than 30 years.
>> > And I work with an old SCM machine with a Num 1040 control that has a
>> > bank of fiber optic remote io that is one of the things holding me
>> > back from trying to convert it to Linuxcnc.
>> >
>> This has been a wish of mine for a long time.  We need some cheap stuff
> that
>> can be the equ of an opto-isolator, but with a piece of glass or plastic
> fiber up
>> to several feet long as the optical media between them.
>> With power on the rx end, signal losses in the plastic fiber could be
> easily
>> compensated. I can visualize stepper drivers incorporating it, probably at
> no
>> more cost for the pair of fiber sockets than they cost for the full opto-
>> isolation BOM right now.
>>
>> All we would need would be an HE IR LED with a molded in funnel to guide
> the
>> fiber tip to the chip face in the LED.  Some sort of a jacket on the fiber
> to
>> prolong its life if rubbing on something, or to prevent optical crosstalk
> would
>> be needed. The major design problem AISI is in gripping the fiber to
> anchor it
>> at both ends, with long term gripping pressure imprinting itself on the
> fiber
>> creating radiation leaks.  Even glass will do that, but usually over time
> frames
>> that exceed the life of the rest of the machine since technically, glass
> is a
>> super-cooled liquid, flowing visibly over the lifetime of the observer.
>>
>> The led makers have now had 40+ years to design such a package, and I fail
> to
>> understand why it has not happened.
>>
>> Or has it, and I missed the announcement?  Thats a plausible excuse given
> my
>> age and retired status. If anybody would have it on this side of the pond,
>> digikey, and I've only found one candidate so far. Intended to be a
> remoteable
>> indicator, the led is conventional shaped, available in several colors.
> Pricing
>> starts at $2.15 with a 6" light pipe, Available up to 3940" long. :) With
> the far
>> end of that pipe facing into an avalanche mode transistor, mounted exactly
>> the same as the led, and substituted for the BOM that puts the
> opto-isolation
>> into the stepper drivers input circuits, it ought to be essentially free!
> What
>> sort of speed would have TBD.  But I'd certainly have to think its faster
> than
>> the 200 to 300 kilohertz we can now drive a $35 M542 stepper driver.
>>
>> Look at <http://www.bivar.com/portals/0/products/FLPRX.X-XX.pdf>
>>
>> And see what you think of it.
>>
>> One of those in red led, looking at one of these:
>>
>> <http://www.everlight.com/file/ProductFile/PLR135-T9.pdf>
>>
>> Would I think, be a good test bed. Need some smd bypassing of the rx
> supply,
>> and I'm not sure what buffering might be needed to make it actually drive
> the
>> opto's in the stepper driver.  Pulse time distortions are quite small and
> the
>> data rate can be as high as 16 megabaud.
>>
>> Now if I can find where to source the fiber cable it uses in say 10'
>>

Re: [Emc-users] Fiber optic control for CNC

[Ken Strauss]

Also look at
http://media.digikey.com/pdf/data%20sheets/toshiba%20pdfs/fiber-optic%20devi
ces%20toslink.pdf


> -Original Message-
> From: Gene Heskett [mailto:ghesk...@shentel.net]
> Sent: Thursday, April 20, 2017 2:51 PM
> To: emc-users@lists.sourceforge.net
> Subject: Re: [Emc-users] Fiber optic control for CNC
>
> On Thursday 20 April 2017 11:22:03 Todd Zuercher wrote:
>
> > Fanuc has been using fiber optic connections for more than 30 years.
> > And I work with an old SCM machine with a Num 1040 control that has a
> > bank of fiber optic remote io that is one of the things holding me
> > back from trying to convert it to Linuxcnc.
> >
> This has been a wish of mine for a long time.  We need some cheap stuff
that
> can be the equ of an opto-isolator, but with a piece of glass or plastic
fiber up
> to several feet long as the optical media between them.
> With power on the rx end, signal losses in the plastic fiber could be
easily
> compensated. I can visualize stepper drivers incorporating it, probably at
no
> more cost for the pair of fiber sockets than they cost for the full opto-
> isolation BOM right now.
>
> All we would need would be an HE IR LED with a molded in funnel to guide
the
> fiber tip to the chip face in the LED.  Some sort of a jacket on the fiber
to
> prolong its life if rubbing on something, or to prevent optical crosstalk
would
> be needed. The major design problem AISI is in gripping the fiber to
anchor it
> at both ends, with long term gripping pressure imprinting itself on the
fiber
> creating radiation leaks.  Even glass will do that, but usually over time
frames
> that exceed the life of the rest of the machine since technically, glass
is a
> super-cooled liquid, flowing visibly over the lifetime of the observer.
>
> The led makers have now had 40+ years to design such a package, and I fail
to
> understand why it has not happened.
>
> Or has it, and I missed the announcement?  Thats a plausible excuse given
my
> age and retired status. If anybody would have it on this side of the pond,
> digikey, and I've only found one candidate so far. Intended to be a
remoteable
> indicator, the led is conventional shaped, available in several colors.
Pricing
> starts at $2.15 with a 6" light pipe, Available up to 3940" long. :) With
the far
> end of that pipe facing into an avalanche mode transistor, mounted exactly
> the same as the led, and substituted for the BOM that puts the
opto-isolation
> into the stepper drivers input circuits, it ought to be essentially free!
What
> sort of speed would have TBD.  But I'd certainly have to think its faster
than
> the 200 to 300 kilohertz we can now drive a $35 M542 stepper driver.
>
> Look at <http://www.bivar.com/portals/0/products/FLPRX.X-XX.pdf>
>
> And see what you think of it.
>
> One of those in red led, looking at one of these:
>
> <http://www.everlight.com/file/ProductFile/PLR135-T9.pdf>
>
> Would I think, be a good test bed. Need some smd bypassing of the rx
supply,
> and I'm not sure what buffering might be needed to make it actually drive
the
> opto's in the stepper driver.  Pulse time distortions are quite small and
the
> data rate can be as high as 16 megabaud.
>
> Now if I can find where to source the fiber cable it uses in say 10'
> pieces, I could try it out in this lathe conversion. With 10 40"
> assemblies, I could put feet and sheet metal between the pi-7i90 and the
> noise makers already installed.  With 30 of them I could replace the
copper
> leaving the pi's box, except for the power cord, with fiber, and enjoy the
> peace and quiet.
>
> And I've got Dennis Strander at DigiKey furiously sending out requests for
> more info. W/O the fibers, we're under a $5 bill a connection so far. I
can live
> with that.  We'll see what falls out of my email box in the next few
hours.
>
> > - Original Message -
> > From: "Gregg Eshelman" <g_ala...@yahoo.com>
> > To: "Enhanced Machine Controller (EMC)"
> > <emc-users@lists.sourceforge.net> Sent: Thursday, April 20, 2017
> > 4:39:08 AM
> > Subject: [Emc-users] Fiber optic control for CNC
> >
> > Looks interesting. Can't have a ground loop when there's no wires.
> > http://hackaday.com/2016/03/20/add-fiber-optic-control-to-your-cnc/
> >
> > --
> > Check out the vibrant tech community on one of the world's
> >most engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> >___
> > Emc-users mailing list
> > Emc-users@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/list

Re: [Emc-users] Fiber optic control for CNC

[Ken Strauss]

Could something like
https://www.digikey.com/catalog/en/partgroup/afbr-1528cz/66628 be useful?
They are about $12 each but operate at 5Mbps so perhaps you could multiplex
some of the signals. There is also an eval kit
https://www.digikey.com/products/en/development-boards-kits-programmers/eval
uation-and-demonstration-boards-and-kits/787?k=hfbr-1506amz  You can get
10-foot fibre patch cables with SMA terminations to avoid making your own.

> -Original Message-
> From: Gene Heskett [mailto:ghesk...@shentel.net]
> Sent: Thursday, April 20, 2017 2:51 PM
> To: emc-users@lists.sourceforge.net
> Subject: Re: [Emc-users] Fiber optic control for CNC
>
> On Thursday 20 April 2017 11:22:03 Todd Zuercher wrote:
>
> > Fanuc has been using fiber optic connections for more than 30 years.
> > And I work with an old SCM machine with a Num 1040 control that has a
> > bank of fiber optic remote io that is one of the things holding me
> > back from trying to convert it to Linuxcnc.
> >
> This has been a wish of mine for a long time.  We need some cheap stuff
that
> can be the equ of an opto-isolator, but with a piece of glass or plastic
fiber up
> to several feet long as the optical media between them.
> With power on the rx end, signal losses in the plastic fiber could be
easily
> compensated. I can visualize stepper drivers incorporating it, probably at
no
> more cost for the pair of fiber sockets than they cost for the full opto-
> isolation BOM right now.
>
> All we would need would be an HE IR LED with a molded in funnel to guide
the
> fiber tip to the chip face in the LED.  Some sort of a jacket on the fiber
to
> prolong its life if rubbing on something, or to prevent optical crosstalk
would
> be needed. The major design problem AISI is in gripping the fiber to
anchor it
> at both ends, with long term gripping pressure imprinting itself on the
fiber
> creating radiation leaks.  Even glass will do that, but usually over time
frames
> that exceed the life of the rest of the machine since technically, glass
is a
> super-cooled liquid, flowing visibly over the lifetime of the observer.
>
> The led makers have now had 40+ years to design such a package, and I fail
to
> understand why it has not happened.
>
> Or has it, and I missed the announcement?  Thats a plausible excuse given
my
> age and retired status. If anybody would have it on this side of the pond,
> digikey, and I've only found one candidate so far. Intended to be a
remoteable
> indicator, the led is conventional shaped, available in several colors.
Pricing
> starts at $2.15 with a 6" light pipe, Available up to 3940" long. :) With
the far
> end of that pipe facing into an avalanche mode transistor, mounted exactly
> the same as the led, and substituted for the BOM that puts the
opto-isolation
> into the stepper drivers input circuits, it ought to be essentially free!
What
> sort of speed would have TBD.  But I'd certainly have to think its faster
than
> the 200 to 300 kilohertz we can now drive a $35 M542 stepper driver.
>
> Look at <http://www.bivar.com/portals/0/products/FLPRX.X-XX.pdf>
>
> And see what you think of it.
>
> One of those in red led, looking at one of these:
>
> <http://www.everlight.com/file/ProductFile/PLR135-T9.pdf>
>
> Would I think, be a good test bed. Need some smd bypassing of the rx
supply,
> and I'm not sure what buffering might be needed to make it actually drive
the
> opto's in the stepper driver.  Pulse time distortions are quite small and
the
> data rate can be as high as 16 megabaud.
>
> Now if I can find where to source the fiber cable it uses in say 10'
> pieces, I could try it out in this lathe conversion. With 10 40"
> assemblies, I could put feet and sheet metal between the pi-7i90 and the
> noise makers already installed.  With 30 of them I could replace the
copper
> leaving the pi's box, except for the power cord, with fiber, and enjoy the
> peace and quiet.
>
> And I've got Dennis Strander at DigiKey furiously sending out requests for
> more info. W/O the fibers, we're under a $5 bill a connection so far. I
can live
> with that.  We'll see what falls out of my email box in the next few
hours.
>
> > - Original Message -
> > From: "Gregg Eshelman" <g_ala...@yahoo.com>
> > To: "Enhanced Machine Controller (EMC)"
> > <emc-users@lists.sourceforge.net> Sent: Thursday, April 20, 2017
> > 4:39:08 AM
> > Subject: [Emc-users] Fiber optic control for CNC
> >
> > Looks interesting. Can't have a ground loop when there's no wires.
> > http://hackaday.com/2016/03/20/add-fiber-optic-control-to-your-cnc/
> >
> > --

Re: [Emc-users] Fiber optic control for CNC

[Chris Albertson]

Fiber optics is not hard to use.   One of the easiest systems is the
one used for audio cables in your TV set and stereo.  they call it
Toslink digital audio or S/PDIF.  You buy the cables with ends
attached at Best Buy or way-cheeper at monoprice.com   Using a
consumer cable makes it easy to buy and cheap.

The sockets you need on both ends are active 5 volt devices that act
like TTL buffer chips or like opto isolators.  Place a 5V logic signal
in one end and it comes out the other.  The sockets are mass produced
for the consumer market and are not expensive, about a buck each end.
  Can go about 20MHz   Toshiba makes them and I'd guess others too.
Digikey, Mouser and other sell them.  They work EXACTLY like opto
isolators.

There is another kind of fiber you can buy cheap and easy that is
intended for Ethernet.   This is another mass market product that is
easy to find.   Bt you can't cable the cables at Best Buy and it costs
more but this system goes up to 1 GHz if you buy the right kind

You want a system where the cables are available at retail outlets and
are already cut and terminated at each end.Toslink uses cheap
plastic cable and is limited length.  But I've used the Ethernet kind
and we bought it on a two kilometer spool.  Terminating bulk glass
fiber is a skill, about as hard as hand soldering BNC or N connectors
on coax.

Possible the BEST why to use fiber for CNC that would require zero
modifications and using only off the shelf stuff is to get an Ethernet
linked Mesa FPGA board and use a fiber segment to connect the Mesa
card to the PC. But WHY???  Cat 5 wired Ethernet is already
galvanically isolated using tiny transformers on each end.   THAT is
one of the best parts of Ethernet.  But fiber is even lightening proof
if you need that.


On Thu, Apr 20, 2017 at 11:51 AM, Gene Heskett  wrote:
> On Thursday 20 April 2017 11:22:03 Todd Zuercher wrote:
>
>> Fanuc has been using fiber optic connections for more than 30 years.
>> And I work with an old SCM machine with a Num 1040 control that has a
>> bank of fiber optic remote io that is one of the things holding me
>> back from trying to convert it to Linuxcnc.
>>
> This has been a wish of mine for a long time.  We need some cheap stuff
> that can be the equ of an opto-isolator, but with a piece of glass or
> plastic fiber up to several feet long as the optical media between them.
> With power on the rx end, signal losses in the plastic fiber could be
> easily compensated. I can visualize stepper drivers incorporating it,
> probably at no more cost for the pair of fiber sockets than they cost
> for the full opto-isolation BOM right now.
>
> All we would need would be an HE IR LED with a molded in funnel to guide
> the fiber tip to the chip face in the LED.  Some sort of a jacket on the
> fiber to prolong its life if rubbing on something, or to prevent optical
> crosstalk would be needed. The major design problem AISI is in gripping
> the fiber to anchor it at both ends, with long term gripping pressure
> imprinting itself on the fiber creating radiation leaks.  Even glass
> will do that, but usually over time frames that exceed the life of the
> rest of the machine since technically, glass is a super-cooled liquid,
> flowing visibly over the lifetime of the observer.
>
> The led makers have now had 40+ years to design such a package, and I
> fail to understand why it has not happened.
>
> Or has it, and I missed the announcement?  Thats a plausible excuse given
> my age and retired status. If anybody would have it on this side of the
> pond, digikey, and I've only found one candidate so far. Intended to be
> a remoteable indicator, the led is conventional shaped, available in
> several colors.  Pricing starts at $2.15 with a 6" light pipe, Available
> up to 3940" long. :) With the far end of that pipe facing into an
> avalanche mode transistor, mounted exactly the same as the led, and
> substituted for the BOM that puts the opto-isolation into the stepper
> drivers input circuits, it ought to be essentially free! What sort of
> speed would have TBD.  But I'd certainly have to think its faster than
> the 200 to 300 kilohertz we can now drive a $35 M542 stepper driver.
>
> Look at 
>
> And see what you think of it.
>
> One of those in red led, looking at one of these:
>
> 
>
> Would I think, be a good test bed. Need some smd bypassing of the rx
> supply, and I'm not sure what buffering might be needed to make it
> actually drive the opto's in the stepper driver.  Pulse time distortions
> are quite small and the data rate can be as high as 16 megabaud.
>
> Now if I can find where to source the fiber cable it uses in say 10'
> pieces, I could try it out in this lathe conversion. With 10 40"
> assemblies, I could put feet and sheet metal between the pi-7i90 and the
> noise makers already installed.  With 30 of 

Re: [Emc-users] Fiber optic control for CNC

[Gene Heskett]

On Thursday 20 April 2017 11:22:03 Todd Zuercher wrote:

> Fanuc has been using fiber optic connections for more than 30 years. 
> And I work with an old SCM machine with a Num 1040 control that has a
> bank of fiber optic remote io that is one of the things holding me
> back from trying to convert it to Linuxcnc.
>
This has been a wish of mine for a long time.  We need some cheap stuff 
that can be the equ of an opto-isolator, but with a piece of glass or 
plastic fiber up to several feet long as the optical media between them. 
With power on the rx end, signal losses in the plastic fiber could be 
easily compensated. I can visualize stepper drivers incorporating it, 
probably at no more cost for the pair of fiber sockets than they cost 
for the full opto-isolation BOM right now.

All we would need would be an HE IR LED with a molded in funnel to guide 
the fiber tip to the chip face in the LED.  Some sort of a jacket on the 
fiber to prolong its life if rubbing on something, or to prevent optical 
crosstalk would be needed. The major design problem AISI is in gripping 
the fiber to anchor it at both ends, with long term gripping pressure 
imprinting itself on the fiber creating radiation leaks.  Even glass 
will do that, but usually over time frames that exceed the life of the 
rest of the machine since technically, glass is a super-cooled liquid, 
flowing visibly over the lifetime of the observer.

The led makers have now had 40+ years to design such a package, and I 
fail to understand why it has not happened.

Or has it, and I missed the announcement?  Thats a plausible excuse given 
my age and retired status. If anybody would have it on this side of the 
pond, digikey, and I've only found one candidate so far. Intended to be 
a remoteable indicator, the led is conventional shaped, available in 
several colors.  Pricing starts at $2.15 with a 6" light pipe, Available 
up to 3940" long. :) With the far end of that pipe facing into an 
avalanche mode transistor, mounted exactly the same as the led, and 
substituted for the BOM that puts the opto-isolation into the stepper 
drivers input circuits, it ought to be essentially free! What sort of 
speed would have TBD.  But I'd certainly have to think its faster than 
the 200 to 300 kilohertz we can now drive a $35 M542 stepper driver.

Look at 

And see what you think of it.

One of those in red led, looking at one of these:



Would I think, be a good test bed. Need some smd bypassing of the rx 
supply, and I'm not sure what buffering might be needed to make it 
actually drive the opto's in the stepper driver.  Pulse time distortions 
are quite small and the data rate can be as high as 16 megabaud.

Now if I can find where to source the fiber cable it uses in say 10' 
pieces, I could try it out in this lathe conversion. With 10 40" 
assemblies, I could put feet and sheet metal between the pi-7i90 and the 
noise makers already installed.  With 30 of them I could replace the 
copper leaving the pi's box, except for the power cord, with fiber, and 
enjoy the peace and quiet.

And I've got Dennis Strander at DigiKey furiously sending out requests 
for more info. W/O the fibers, we're under a $5 bill a connection so 
far. I can live with that.  We'll see what falls out of my email box in 
the next few hours.

> - Original Message -
> From: "Gregg Eshelman" 
> To: "Enhanced Machine Controller (EMC)"
>  Sent: Thursday, April 20, 2017
> 4:39:08 AM
> Subject: [Emc-users] Fiber optic control for CNC
>
> Looks interesting. Can't have a ground loop when there's no wires.
> http://hackaday.com/2016/03/20/add-fiber-optic-control-to-your-cnc/
>
> --
> Check out the vibrant tech community on one of the world's
> most engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users
>
> --
> Check out the vibrant tech community on one of the world's
> most engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users


Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

--
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot

Re: [Emc-users] Fiber optic control for CNC

[Todd Zuercher]

Fanuc has been using fiber optic connections for more than 30 years.  And I 
work with an old SCM machine with a Num 1040 control that has a bank of fiber 
optic remote io that is one of the things holding me back from trying to 
convert it to Linuxcnc.

- Original Message -
From: "Gregg Eshelman" 
To: "Enhanced Machine Controller (EMC)" 
Sent: Thursday, April 20, 2017 4:39:08 AM
Subject: [Emc-users] Fiber optic control for CNC

Looks interesting. Can't have a ground loop when there's no wires.
http://hackaday.com/2016/03/20/add-fiber-optic-control-to-your-cnc/

--
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