Re: GW-DEC-1: A New DEC Prototyping Board
As Jon said, from my analysis of busted-apart DEC connectors, there's a selectively plated "pad" where the contact surface actually is. I wouldn't be surprised if the bulk of the contact fingers is *phosphor bronze* which is often used in springs. Perhaps we can get Connor to do a metallurgical analysis once he gets the EDX attachment for his SEM going! Thanks, Jonathan On Fri, Aug 16, 2019 at 10:21 PM Jon Elson via cctalk wrote: > On 08/16/2019 05:59 PM, Noel Chiappa via cctalk wrote: > > > From: Brent Hilpert > > > > > I've seen pieces of HP high-end lab equipment from thru the 60s > that > > > used tin plating on the PCB edge fingers, mating into gold-plated > edge > > > connectors on the backplane. > > > > ISTR that DEC used bronze contacts in their backplanes, but basically > all the > > boards had gold-plated fingers. (I think I've seen a few power supply > boards > > that had tinned fingers.) > > > > I think the bronze was preferred since the contacts bend back and forth > as > > cards are inserted/removed, and bronze is more durable; and being part > tin, > > has the same corrosion characteristics are the tin. > > > > Noel > > > The contacts were mostly phosphor bronze, but they had a > little spot of selectively plated gold where the PC board > finger actually wiped. I think they used basically the same > technology from the PDP-8 era to the VAX 7xx series. > > Jon > > Jon >
Re: GW-DEC-1: A New DEC Prototyping Board
On 08/16/2019 05:59 PM, Noel Chiappa via cctalk wrote: > From: Brent Hilpert > I've seen pieces of HP high-end lab equipment from thru the 60s that > used tin plating on the PCB edge fingers, mating into gold-plated edge > connectors on the backplane. ISTR that DEC used bronze contacts in their backplanes, but basically all the boards had gold-plated fingers. (I think I've seen a few power supply boards that had tinned fingers.) I think the bronze was preferred since the contacts bend back and forth as cards are inserted/removed, and bronze is more durable; and being part tin, has the same corrosion characteristics are the tin. Noel The contacts were mostly phosphor bronze, but they had a little spot of selectively plated gold where the PC board finger actually wiped. I think they used basically the same technology from the PDP-8 era to the VAX 7xx series. Jon Jon
Re: GW-DEC-1: A New DEC Prototyping Board
> From: Brent Hilpert > I've seen pieces of HP high-end lab equipment from thru the 60s that > used tin plating on the PCB edge fingers, mating into gold-plated edge > connectors on the backplane. ISTR that DEC used bronze contacts in their backplanes, but basically all the boards had gold-plated fingers. (I think I've seen a few power supply boards that had tinned fingers.) I think the bronze was preferred since the contacts bend back and forth as cards are inserted/removed, and bronze is more durable; and being part tin, has the same corrosion characteristics are the tin. Noel
Re: GW-DEC-1: A New DEC Prototyping Board
On 8/16/19 5:46 PM, Brent Hilpert via cctalk wrote:
> On 2019-Aug-16, at 11:56 AM, systems_glitch via cctalk wrote:
>> On Fri, Aug 16, 2019 at 2:53 PM Paul Koning wrote:
>>>
On Aug 16, 2019, at 2:43 PM, systems_glitch via cctalk <
I'm sure DEC wouldn't have bothered with hard gold plating if their
connectors were metallurgically incompatible :P The few busted DEC
connectors I've replaced did indeed have selective gold plating on the
contact surfaces. Most quality edge connector slots are similarly
constructed.
>>>
>>> It's been a while and I never looked in depth, but it most definitely is
>>> not true that gold is only compatible with gold.
>>>
>>> From what I remember, the detailed analysis involves an "electrochemical
>>> series", which has metals like sodium at one end, copper closer to the
>>> middle, and gold at or near the other end. Metals are compatible if their
>>> potential value differs by less than a limit. The limit depends on the
>>> environment; in an office you can have a larger limit than on a ship where
>>> you have salt spray, or a tire factory with lots of SO2 in the air.
>>>
>>> There are also some twists; I think stainless steel is compatible with
>>> many things thanks to the alloy ("stainless") properties. In fact, I think
>>> the subject came up in connection with failure analysis of coin cell
>>> battery holders. The battery cases are stainless steel; the question is
>>> what contacts are acceptable. Gold is; there may be others but some things
>>> that are used in the market are not good choices.
>
>> You can look it up in an electronegativity chart for a quick "will these
>> ruin each other" check.
>>
>> I think a lot of this comes from the SIMM era in PCs, where folks were told
>> to only use gold-flash SIMMs in gold sockets, and only tin plated SIMMs in
>> tin plated sockets.
>
>
> I've seen pieces of HP high-end lab equipment from thru the 60s that used tin
> plating on the PCB edge fingers, mating into gold-plated edge connectors on
> the backplane.
> Never quiet understood it, they (HP) were doing gold-plated edge fingers on
> other equipment at the same time.
>
>
Back in the dark ages when MITS Altair (and dirt) was new
Initial board were tin and not the fancy stuff either, sockets were
commonly gold. then came the occasional gold. What was nasty was the
gold over copper not gold/nickel/copper... Can you say Electromigration
and green plague? It was the cause of the shake well disorder as in
before powering up, pull the board and wipe the edge connector,
re-insert boards and it would be hopefully stable, maybe. I had to
retire that machine after about 2 years it was so flakey due to that.
By then the suspect boards were retired and never used again.
Looking back and having it to look at part of the issue was crappy gold
plating (looked good) and also some of the sockets did not have a hard
wipe or high spring tension both of which were likely causative.
I've not see that anywhere else. Dec connector blocks are hard wipe
and very good at what they do, make a connection. Even tin plate seems
to be no trouble at all.
Allison
Re: GW-DEC-1: A New DEC Prototyping Board
That *is* surprising, HP sometimes gold plated the whole thing!
In any case, I will continue to run edge connectors with the superior
albeit more expensive selective hard gold process :P
Thanks,
Jonathan
On Fri, Aug 16, 2019 at 5:46 PM Brent Hilpert via cctalk <
cctalk@classiccmp.org> wrote:
> On 2019-Aug-16, at 11:56 AM, systems_glitch via cctalk wrote:
> > On Fri, Aug 16, 2019 at 2:53 PM Paul Koning
> wrote:
> >>
> >>> On Aug 16, 2019, at 2:43 PM, systems_glitch via cctalk <
> >>>
> >>> I'm sure DEC wouldn't have bothered with hard gold plating if their
> >>> connectors were metallurgically incompatible :P The few busted DEC
> >>> connectors I've replaced did indeed have selective gold plating on the
> >>> contact surfaces. Most quality edge connector slots are similarly
> >>> constructed.
> >>
> >> It's been a while and I never looked in depth, but it most definitely is
> >> not true that gold is only compatible with gold.
> >>
> >> From what I remember, the detailed analysis involves an "electrochemical
> >> series", which has metals like sodium at one end, copper closer to the
> >> middle, and gold at or near the other end. Metals are compatible if
> their
> >> potential value differs by less than a limit. The limit depends on the
> >> environment; in an office you can have a larger limit than on a ship
> where
> >> you have salt spray, or a tire factory with lots of SO2 in the air.
> >>
> >> There are also some twists; I think stainless steel is compatible with
> >> many things thanks to the alloy ("stainless") properties. In fact, I
> think
> >> the subject came up in connection with failure analysis of coin cell
> >> battery holders. The battery cases are stainless steel; the question is
> >> what contacts are acceptable. Gold is; there may be others but some
> things
> >> that are used in the market are not good choices.
>
> > You can look it up in an electronegativity chart for a quick "will these
> > ruin each other" check.
> >
> > I think a lot of this comes from the SIMM era in PCs, where folks were
> told
> > to only use gold-flash SIMMs in gold sockets, and only tin plated SIMMs
> in
> > tin plated sockets.
>
>
> I've seen pieces of HP high-end lab equipment from thru the 60s that used
> tin plating on the PCB edge fingers, mating into gold-plated edge
> connectors on the backplane.
> Never quiet understood it, they (HP) were doing gold-plated edge fingers
> on other equipment at the same time.
>
>
>
Re: GW-DEC-1: A New DEC Prototyping Board
On 2019-Aug-16, at 11:56 AM, systems_glitch via cctalk wrote:
> On Fri, Aug 16, 2019 at 2:53 PM Paul Koning wrote:
>>
>>> On Aug 16, 2019, at 2:43 PM, systems_glitch via cctalk <
>>>
>>> I'm sure DEC wouldn't have bothered with hard gold plating if their
>>> connectors were metallurgically incompatible :P The few busted DEC
>>> connectors I've replaced did indeed have selective gold plating on the
>>> contact surfaces. Most quality edge connector slots are similarly
>>> constructed.
>>
>> It's been a while and I never looked in depth, but it most definitely is
>> not true that gold is only compatible with gold.
>>
>> From what I remember, the detailed analysis involves an "electrochemical
>> series", which has metals like sodium at one end, copper closer to the
>> middle, and gold at or near the other end. Metals are compatible if their
>> potential value differs by less than a limit. The limit depends on the
>> environment; in an office you can have a larger limit than on a ship where
>> you have salt spray, or a tire factory with lots of SO2 in the air.
>>
>> There are also some twists; I think stainless steel is compatible with
>> many things thanks to the alloy ("stainless") properties. In fact, I think
>> the subject came up in connection with failure analysis of coin cell
>> battery holders. The battery cases are stainless steel; the question is
>> what contacts are acceptable. Gold is; there may be others but some things
>> that are used in the market are not good choices.
> You can look it up in an electronegativity chart for a quick "will these
> ruin each other" check.
>
> I think a lot of this comes from the SIMM era in PCs, where folks were told
> to only use gold-flash SIMMs in gold sockets, and only tin plated SIMMs in
> tin plated sockets.
I've seen pieces of HP high-end lab equipment from thru the 60s that used tin
plating on the PCB edge fingers, mating into gold-plated edge connectors on the
backplane.
Never quiet understood it, they (HP) were doing gold-plated edge fingers on
other equipment at the same time.
Re: GW-DEC-1: A New DEC Prototyping Board
On 8/16/2019 12:53 PM, Paul Koning via cctalk wrote:
From what I remember, the detailed analysis involves an "electrochemical
series", which has metals like sodium at one end, copper closer to the middle, and
gold at or near the other end. Metals are compatible if their potential value differs by
less than a limit. The limit depends on the environment; in an office you can have a
larger limit than on a ship where you have salt spray, or a tire factory with lots of SO2
in the air.
There are also some twists; I think stainless steel is compatible with many things thanks
to the alloy ("stainless") properties. In fact, I think the subject came up in
connection with failure analysis of coin cell battery holders. The battery cases are
stainless steel; the question is what contacts are acceptable. Gold is; there may be
others but some things that are used in the market are not good choices.
paul
That reminds me, Tubes and More ( https://www.tubesandmore.com ) sell a
contact cleaner used for vacuum tubes. That may be useful for cleaning
cards and card edge sockets. Deoxit is the product and comes in assorted
types depending what you are cleaning.
Ben.
Re: GW-DEC-1: A New DEC Prototyping Board
You can look it up in an electronegativity chart for a quick "will these
ruin each other" check.
I think a lot of this comes from the SIMM era in PCs, where folks were told
to only use gold-flash SIMMs in gold sockets, and only tin plated SIMMs in
tin plated sockets.
Thanks,
Jonathan
On Fri, Aug 16, 2019 at 2:53 PM Paul Koning wrote:
>
>
> > On Aug 16, 2019, at 2:43 PM, systems_glitch via cctalk <
> cctalk@classiccmp.org> wrote:
> >
> > I'm sure DEC wouldn't have bothered with hard gold plating if their
> > connectors were metallurgically incompatible :P The few busted DEC
> > connectors I've replaced did indeed have selective gold plating on the
> > contact surfaces. Most quality edge connector slots are similarly
> > constructed.
>
> It's been a while and I never looked in depth, but it most definitely is
> not true that gold is only compatible with gold.
>
> From what I remember, the detailed analysis involves an "electrochemical
> series", which has metals like sodium at one end, copper closer to the
> middle, and gold at or near the other end. Metals are compatible if their
> potential value differs by less than a limit. The limit depends on the
> environment; in an office you can have a larger limit than on a ship where
> you have salt spray, or a tire factory with lots of SO2 in the air.
>
> There are also some twists; I think stainless steel is compatible with
> many things thanks to the alloy ("stainless") properties. In fact, I think
> the subject came up in connection with failure analysis of coin cell
> battery holders. The battery cases are stainless steel; the question is
> what contacts are acceptable. Gold is; there may be others but some things
> that are used in the market are not good choices.
>
> paul
>
> > On Fri, Aug 16, 2019 at 2:27 PM ben via cctalk
> > wrote:
> >
> >> On 8/16/2019 12:13 PM, systems_glitch via cctalk wrote:
> >>> Dwight,
> >>>
> >>> I spot check boards. I lack sufficiently sensitive instruments to
> measure
> >>> actual thickness (even on a surface plate, it's the same for ENIG as
> hard
> >>> gold with an 0.0001" indicator) but ENIG won't stand up to a few swipes
> >>> with an ink eraser, whereas hard gold will stand up to it no problem.
> The
> >>> main issue I've seen, in buying other people's products and projects,
> is
> >>> board houses passing off ENIG as hard gold (and charging for it!) or
> >>> claiming they're using "extra heavy ENIG" -- which of course isn't a
> >> thing,
> >>> because ENIG is an ion swap!
> >>>
> >>> Thanks,
> >>> Jonathan
> >>
> >> Is gold plating the best thing? I thought that gold plating only works
> >> best when matching other gold connections.
> >> Ben.
> >>
> >>
>
>
Re: GW-DEC-1: A New DEC Prototyping Board
> On Aug 16, 2019, at 2:43 PM, systems_glitch via cctalk
> wrote:
>
> I'm sure DEC wouldn't have bothered with hard gold plating if their
> connectors were metallurgically incompatible :P The few busted DEC
> connectors I've replaced did indeed have selective gold plating on the
> contact surfaces. Most quality edge connector slots are similarly
> constructed.
It's been a while and I never looked in depth, but it most definitely is not
true that gold is only compatible with gold.
From what I remember, the detailed analysis involves an "electrochemical
series", which has metals like sodium at one end, copper closer to the middle,
and gold at or near the other end. Metals are compatible if their potential
value differs by less than a limit. The limit depends on the environment; in
an office you can have a larger limit than on a ship where you have salt spray,
or a tire factory with lots of SO2 in the air.
There are also some twists; I think stainless steel is compatible with many
things thanks to the alloy ("stainless") properties. In fact, I think the
subject came up in connection with failure analysis of coin cell battery
holders. The battery cases are stainless steel; the question is what contacts
are acceptable. Gold is; there may be others but some things that are used in
the market are not good choices.
paul
> On Fri, Aug 16, 2019 at 2:27 PM ben via cctalk
> wrote:
>
>> On 8/16/2019 12:13 PM, systems_glitch via cctalk wrote:
>>> Dwight,
>>>
>>> I spot check boards. I lack sufficiently sensitive instruments to measure
>>> actual thickness (even on a surface plate, it's the same for ENIG as hard
>>> gold with an 0.0001" indicator) but ENIG won't stand up to a few swipes
>>> with an ink eraser, whereas hard gold will stand up to it no problem. The
>>> main issue I've seen, in buying other people's products and projects, is
>>> board houses passing off ENIG as hard gold (and charging for it!) or
>>> claiming they're using "extra heavy ENIG" -- which of course isn't a
>> thing,
>>> because ENIG is an ion swap!
>>>
>>> Thanks,
>>> Jonathan
>>
>> Is gold plating the best thing? I thought that gold plating only works
>> best when matching other gold connections.
>> Ben.
>>
>>
Re: GW-DEC-1: A New DEC Prototyping Board
I'm sure DEC wouldn't have bothered with hard gold plating if their connectors were metallurgically incompatible :P The few busted DEC connectors I've replaced did indeed have selective gold plating on the contact surfaces. Most quality edge connector slots are similarly constructed. Thanks, Jonathan On Fri, Aug 16, 2019 at 2:27 PM ben via cctalk wrote: > On 8/16/2019 12:13 PM, systems_glitch via cctalk wrote: > > Dwight, > > > > I spot check boards. I lack sufficiently sensitive instruments to measure > > actual thickness (even on a surface plate, it's the same for ENIG as hard > > gold with an 0.0001" indicator) but ENIG won't stand up to a few swipes > > with an ink eraser, whereas hard gold will stand up to it no problem. The > > main issue I've seen, in buying other people's products and projects, is > > board houses passing off ENIG as hard gold (and charging for it!) or > > claiming they're using "extra heavy ENIG" -- which of course isn't a > thing, > > because ENIG is an ion swap! > > > > Thanks, > > Jonathan > > Is gold plating the best thing? I thought that gold plating only works > best when matching other gold connections. > Ben. > >
Re: GW-DEC-1: A New DEC Prototyping Board
On 8/16/2019 12:13 PM, systems_glitch via cctalk wrote: Dwight, I spot check boards. I lack sufficiently sensitive instruments to measure actual thickness (even on a surface plate, it's the same for ENIG as hard gold with an 0.0001" indicator) but ENIG won't stand up to a few swipes with an ink eraser, whereas hard gold will stand up to it no problem. The main issue I've seen, in buying other people's products and projects, is board houses passing off ENIG as hard gold (and charging for it!) or claiming they're using "extra heavy ENIG" -- which of course isn't a thing, because ENIG is an ion swap! Thanks, Jonathan Is gold plating the best thing? I thought that gold plating only works best when matching other gold connections. Ben.
Re: GW-DEC-1: A New DEC Prototyping Board
Dwight, I spot check boards. I lack sufficiently sensitive instruments to measure actual thickness (even on a surface plate, it's the same for ENIG as hard gold with an 0.0001" indicator) but ENIG won't stand up to a few swipes with an ink eraser, whereas hard gold will stand up to it no problem. The main issue I've seen, in buying other people's products and projects, is board houses passing off ENIG as hard gold (and charging for it!) or claiming they're using "extra heavy ENIG" -- which of course isn't a thing, because ENIG is an ion swap! Thanks, Jonathan On Fri, Aug 16, 2019 at 1:14 PM dwight via cctalk wrote: > I was wondering, does anyone check the thickness of the gold plating > anymore. Years ago, working at another large company, we saw quite a bit of > cheating on this. > Trust but verity. > Dwight > > > From: cctalk on behalf of Dennis Boone > via cctalk > Sent: Friday, August 16, 2019 8:46 AM > To: cctalk@classiccmp.org > Subject: Re: GW-DEC-1: A New DEC Prototyping Board > > > I've gotten the distinct impression that US board houses really are > > only interested in government/military/aerospace work. I've often > > wondered what it would take to set up a modern "no human interaction" > > line and if one could be even a little competitive with the Chinese > > on it. > > Based on a couple of youtube videos I've seen in the last year (sorry, > don't have links), I'm not sure it's entirely fair to describe the > Chinese board house process as "no human interaction". I mean, sure, > web form submission, but they seem to have a lot of "engineers" checking > designs, and factory workers, and... > > De >
Re: GW-DEC-1: A New DEC Prototyping Board
I was wondering, does anyone check the thickness of the gold plating anymore. Years ago, working at another large company, we saw quite a bit of cheating on this. Trust but verity. Dwight From: cctalk on behalf of Dennis Boone via cctalk Sent: Friday, August 16, 2019 8:46 AM To: cctalk@classiccmp.org Subject: Re: GW-DEC-1: A New DEC Prototyping Board > I've gotten the distinct impression that US board houses really are > only interested in government/military/aerospace work. I've often > wondered what it would take to set up a modern "no human interaction" > line and if one could be even a little competitive with the Chinese > on it. Based on a couple of youtube videos I've seen in the last year (sorry, don't have links), I'm not sure it's entirely fair to describe the Chinese board house process as "no human interaction". I mean, sure, web form submission, but they seem to have a lot of "engineers" checking designs, and factory workers, and... De
Re: GW-DEC-1: A New DEC Prototyping Board
> I've gotten the distinct impression that US board houses really are > only interested in government/military/aerospace work. I've often > wondered what it would take to set up a modern "no human interaction" > line and if one could be even a little competitive with the Chinese > on it. Based on a couple of youtube videos I've seen in the last year (sorry, don't have links), I'm not sure it's entirely fair to describe the Chinese board house process as "no human interaction". I mean, sure, web form submission, but they seem to have a lot of "engineers" checking designs, and factory workers, and... De
Re: GW-DEC-1: A New DEC Prototyping Board
Indeed, when I tried to get quotes for the first XT-IDE run, the best US-based quote I got was around $15/board with a *16 WEEK* lead time. Compare to my usual "does good hard gold" shop in China, PCB Cart, at $8/board (final all-in cost) and 12 day lead time, including the initial tooling fees. PCB Cart is the same shop that the former N8VEM project, s100computers.com, etc. have used for their work, so they've got a long, solid track record with the hobbyist community. I've gotten the distinct impression that US board houses really are only interested in government/military/aerospace work. I've often wondered what it would take to set up a modern "no human interaction" line and if one could be even a little competitive with the Chinese on it. Thanks, Jonathan On Fri, Aug 16, 2019 at 11:18 AM Jon Elson wrote: > On 08/16/2019 08:59 AM, systems_glitch via cctalk wrote: > > Paul, > > > > I've got a board house I usually use, but if I can find a shop in the USA > > that will do hard gold plating and provide a comparable cost-per-board, > I'd > > certainly switch! > > > > > There are few board houses in the US anymore, and they are > usually doing aerospace or government work, and are quite > expensive. Most of the supposedly US-based outfits now do > almost all their fabrication in China. > > I use E-teknet, based in AZ, but their fabs are in China. > They do VERY good work. In the distant past I did a lot of > boards with US makers, but had a constant problem that they > would charge me for electrical test, and then just cheat and > NOT actually test the boards, just do a visual inspection. > So, I ended up with 4-layer boards with shorts on the inner > layers! And, only found those after stuffing the boards. A > MAJOR pain, and I would blacklist those companies. > Well, E-teknet has never done that to me. (The flying probe > tester leaves TINY dots on the pads, so you can tell whether > a board has been tested or not.) > > Jon >
Re: GW-DEC-1: A New DEC Prototyping Board
On 08/16/2019 08:59 AM, systems_glitch via cctalk wrote: Paul, I've got a board house I usually use, but if I can find a shop in the USA that will do hard gold plating and provide a comparable cost-per-board, I'd certainly switch! There are few board houses in the US anymore, and they are usually doing aerospace or government work, and are quite expensive. Most of the supposedly US-based outfits now do almost all their fabrication in China. I use E-teknet, based in AZ, but their fabs are in China. They do VERY good work. In the distant past I did a lot of boards with US makers, but had a constant problem that they would charge me for electrical test, and then just cheat and NOT actually test the boards, just do a visual inspection. So, I ended up with 4-layer boards with shorts on the inner layers! And, only found those after stuffing the boards. A MAJOR pain, and I would blacklist those companies. Well, E-teknet has never done that to me. (The flying probe tester leaves TINY dots on the pads, so you can tell whether a board has been tested or not.) Jon
Re: GW-DEC-1: A New DEC Prototyping Board
Paul, I've got a board house I usually use, but if I can find a shop in the USA that will do hard gold plating and provide a comparable cost-per-board, I'd certainly switch! Thanks, Jonathan On Fri, Aug 16, 2019 at 12:55 AM Paul Anderson wrote: > Hi Jonathan, > > If you are looking for someone to make the boards, I know someone in CA. > I'll try to dig up his contact info this weekend. > > Paul > > > On Wed, Aug 14, 2019 at 7:14 PM systems_glitch via cctalk < > cctalk@classiccmp.org> wrote: > >> Connor Krukosky and I have been working on laying out a new quad-height >> DEC >> protoboard, which can also be sheared down into a dual-height board. Full >> announce on the VC Forums: >> >> >> http://www.vcfed.org/forum/showthread.php?71177-GW-DEC-1-A-New-Quad-Height-DEC-Prototyping-Board=582892#post582892 >> >> These should be available within a month or so. I'll be putting up a >> preorder soon to gauge interest in the production run, which as usual will >> have hard gold plating on the edge connectors. I haven't gotten a quote >> for >> the cost, but I expect them to be $30-40 each for production boards. >> They'll be available at VCF Midwest as well as online! >> >> Thanks, >> Jonathan >> >
Re: GW-DEC-1: A New DEC Prototyping Board
Hi Jonathan, If you are looking for someone to make the boards, I know someone in CA. I'll try to dig up his contact info this weekend. Paul On Wed, Aug 14, 2019 at 7:14 PM systems_glitch via cctalk < cctalk@classiccmp.org> wrote: > Connor Krukosky and I have been working on laying out a new quad-height DEC > protoboard, which can also be sheared down into a dual-height board. Full > announce on the VC Forums: > > > http://www.vcfed.org/forum/showthread.php?71177-GW-DEC-1-A-New-Quad-Height-DEC-Prototyping-Board=582892#post582892 > > These should be available within a month or so. I'll be putting up a > preorder soon to gauge interest in the production run, which as usual will > have hard gold plating on the edge connectors. I haven't gotten a quote for > the cost, but I expect them to be $30-40 each for production boards. > They'll be available at VCF Midwest as well as online! > > Thanks, > Jonathan >
RE: GW-DEC-1: A New DEC Prototyping Board
-Original Message- From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Noel Chiappa via cctalk Sent: Thursday, August 15, 2019 12:45 PM To: cctalk@classiccmp.org Cc: j...@mercury.lcs.mit.edu Subject: Re: GW-DEC-1: A New DEC Prototyping Board > From: Paul Birkel > But which bus? There are three ... So I'm clearly not very awake this morning. I can only think of two major quad-width DEC standard slots - SPC (UNIBUS) and dual QBUS. What's the third - PMI? (MUD is hex, as is Fastbus.) Or OMNIBUS, if we're not restricted to PDP-11's? Noel - OMNIBUS, yes. Use case: http://tronola.com/html/ram_for_pdp-8e.html -
Re: GW-DEC-1: A New DEC Prototyping Board
> From: Paul Birkel > But which bus? There are three ... So I'm clearly not very awake this morning. I can only think of two major quad-width DEC standard slots - SPC (UNIBUS) and dual QBUS. What's the third - PMI? (MUD is hex, as is Fastbus.) Or OMNIBUS, if we're not restricted to PDP-11's? Noel
Re: GW-DEC-1: A New DEC Prototyping Board
Speaking from experience from having done a few Unibus boards now (none of them available yet unfortunately) that providing a general Unibus interface on a quad board will consume a reasonable amount of the board space and limit flexibility on which driver/receiver/transceiver parts that can be used. That’s just for the Unibus drivers. If you want to actually *run* the interface then you’re talking a lot more stuff. Of course, the boards I’m doing are all SMD (with the exception of the unibus interface parts). I also have to add in 5v to 3.3v conversion. Even on a 4 layer board there’s lots of “congestion” which limits the number of parts that can actually placed on the board. :-( TTFN - Guy > On Aug 15, 2019, at 1:23 AM, emanuel stiebler via cctalk > wrote: > > On 2019-08-15 02:13, systems_glitch via cctalk wrote: >> Connor Krukosky and I have been working on laying out a new quad-height DEC >> protoboard, which can also be sheared down into a dual-height board. Full >> announce on the VC Forums: >> >> http://www.vcfed.org/forum/showthread.php?71177-GW-DEC-1-A-New-Quad-Height-DEC-Prototyping-Board=582892#post582892 > > Was always hoping somebody would do something like that, but with the > bus interface already on it ...
Re: GW-DEC-1: A New DEC Prototyping Board
On 8/14/19 5:13 PM, systems_glitch via cctalk wrote: > These should be available within a month or so. I'll be putting up a > preorder soon to gauge interest in the production run Do all three busses share the same ground pins? Many proto boards I've seen have ground planes on the board backside. Other suggestions I've seen are beefing up the trace widths (esp for the power pins) and changing the pin spacing to be able to use a .1" header for the edge connector pins.
Re: GW-DEC-1: A New DEC Prototyping Board
And then there's things that use the same connector, but it's none of the three more common DEC buses! The need that led to the development of this prototype board is actually replacing missing boards in a VT05! Thanks, Jonathan On Thu, Aug 15, 2019 at 10:21 AM Paul Birkel wrote: > -Original Message- > From: cctech [mailto:cctech-boun...@classiccmp.org] On Behalf Of emanuel > stiebler via cctech > Sent: Thursday, August 15, 2019 4:23 AM > To: systems_glitch; General Discussion: On-Topic and Off-Topic Posts > Subject: Re: GW-DEC-1: A New DEC Prototyping Board > > On 2019-08-15 02:13, systems_glitch via cctalk wrote: > > Connor Krukosky and I have been working on laying out a new quad-height > DEC > > protoboard, which can also be sheared down into a dual-height board. Full > > announce on the VC Forums: > > > > > http://www.vcfed.org/forum/showthread.php?71177-GW-DEC-1-A-New-Quad-Height-DEC-Prototyping-Board=582892#post582892 > > Was always hoping somebody would do something like that, but with the > bus interface already on it ... > > - > > But which bus? There are three ... > > - > >
RE: GW-DEC-1: A New DEC Prototyping Board
-Original Message- From: cctech [mailto:cctech-boun...@classiccmp.org] On Behalf Of emanuel stiebler via cctech Sent: Thursday, August 15, 2019 4:23 AM To: systems_glitch; General Discussion: On-Topic and Off-Topic Posts Subject: Re: GW-DEC-1: A New DEC Prototyping Board On 2019-08-15 02:13, systems_glitch via cctalk wrote: > Connor Krukosky and I have been working on laying out a new quad-height DEC > protoboard, which can also be sheared down into a dual-height board. Full > announce on the VC Forums: > > http://www.vcfed.org/forum/showthread.php?71177-GW-DEC-1-A-New-Quad-Height-DEC-Prototyping-Board=582892#post582892 Was always hoping somebody would do something like that, but with the bus interface already on it ... - But which bus? There are three ... -
Re: GW-DEC-1: A New DEC Prototyping Board
On 2019-08-15 02:13, systems_glitch via cctalk wrote: > Connor Krukosky and I have been working on laying out a new quad-height DEC > protoboard, which can also be sheared down into a dual-height board. Full > announce on the VC Forums: > > http://www.vcfed.org/forum/showthread.php?71177-GW-DEC-1-A-New-Quad-Height-DEC-Prototyping-Board=582892#post582892 Was always hoping somebody would do something like that, but with the bus interface already on it ...
GW-DEC-1: A New DEC Prototyping Board
Connor Krukosky and I have been working on laying out a new quad-height DEC protoboard, which can also be sheared down into a dual-height board. Full announce on the VC Forums: http://www.vcfed.org/forum/showthread.php?71177-GW-DEC-1-A-New-Quad-Height-DEC-Prototyping-Board=582892#post582892 These should be available within a month or so. I'll be putting up a preorder soon to gauge interest in the production run, which as usual will have hard gold plating on the edge connectors. I haven't gotten a quote for the cost, but I expect them to be $30-40 each for production boards. They'll be available at VCF Midwest as well as online! Thanks, Jonathan
