Re: [time-nuts] Opening an Isotemp OCXO

if its the yellow tantalum. then yes 39 uf at 10V. S sort of surprised it didn't go nuclear on you. Makes for a serious mess. Regards Paul WB8TSL On Sat, Oct 29, 2016 at 9:59 AM, Bob Camp wrote: > Hi > > If the OCXO was designed for a ~70 C upper end temperature spec, then a

Re: [time-nuts] Opening an Isotemp OCXO

Hi If the OCXO was designed for a ~70 C upper end temperature spec, then a ~90C crystal would make sense. When you feed +12 into the oven control, you are increasing the effective gain of the control loop (it has more power). The cycling you see is the loop going into oscillation. It’s the

Re: [time-nuts] Opening an Isotemp OCXO

More information; I added a picture to the dropbox from my Flir IR camera. The picture shows the copper block that the crystal is attached to running at about 200 F. In the IR shot the copper block is to the right.In most of the regular pictures it is toward the bottom of the picture.

Re: [time-nuts] Opening an Isotemp OCXO

of precise time and frequency measurement' Subject: Re: [time-nuts] Opening an Isotemp OCXO Sorry. 74S05D. Joe -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of J. L. Trantham Sent: Friday, October 28, 2016 5:50 PM To: 'Tom Miller'; 'Discussion

Re: [time-nuts] Opening an Isotemp OCXO

To: pe...@reilley.com; Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Opening an Isotemp OCXO Can you see the voltage on the yellow dipped tantalum under the board? I think that is what it is. - Original Message - From: "Peter Reilley"

Re: [time-nuts] Opening an Isotemp OCXO

Sorry. 74S05D. Joe -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of J. L. Trantham Sent: Friday, October 28, 2016 5:50 PM To: 'Tom Miller'; 'Discussion of precise time and frequency measurement' Subject: Re: [time-nuts] Opening an Isotemp OCXO I have

Re: [time-nuts] Opening an Isotemp OCXO

:18 PM To: pe...@reilley.com; Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Opening an Isotemp OCXO Can you see the voltage on the yellow dipped tantalum under the board? I think that is what it is. - Original Message - From: "Peter Reilley"

Re: [time-nuts] Opening an Isotemp OCXO

Sent: Friday, October 28, 2016 3:28 PM Subject: Re: [time-nuts] Opening an Isotemp OCXO That seems the most reasonable thing to do. Pete On 10/28/2016 3:20 PM, Tom Miller wrote: It looks like that is the only device that could be damaged by 12 volts. Can you find a replacement and try runni

Re: [time-nuts] Opening an Isotemp OCXO

On 10/28/16 1:09 PM, Bob Stewart wrote: Hi Bob, Can't the OCXOs be characterized pretty closely by someone with the right tools and staff? I don't have a big sample to speak from, but the Trimbles I use only have a couple of ceramic coated pieces, and those can be exposed down to the die by

Re: [time-nuts] Opening an Isotemp OCXO

ies, but given the right tools and employees... > > Bob > > From: Bob Camp <kb...@n1k.org> > To: pe...@reilley.com; Discussion of precise time and frequency measurement > <time-nuts@febo.com> > Sent: Friday, October 28, 2016 2:46 PM > Subject: Re: [time-nuts] Ope

Re: [time-nuts] Opening an Isotemp OCXO

I do not think the designer was considering noise at all because tying the inputs together would not do anything useful. Emitter resistance is inversely proportional to emitter current (26/mA) but putting them in parallel lowers the current through each emitter so the total emitter resistance

Re: [time-nuts] Opening an Isotemp OCXO

From: Peter Reilley <preilley_...@comcast.net> To: Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Friday, October 28, 2016 2:10 PM Subject: Re: [time-nuts] Opening an Isotemp OCXO The reason that there was 12 volts on the unit was because I put it the

Re: [time-nuts] Opening an Isotemp OCXO

<time-nuts@febo.com> Sent: Friday, October 28, 2016 3:10 PM Subject: Re: [time-nuts] Opening an Isotemp OCXO The reason that there was 12 volts on the unit was because I put it there. I should have tried 5 volts first but the only datasheet that I could find said 12 volts. All the eBay

Re: [time-nuts] Opening an Isotemp OCXO

they?  Granted, that's beyond my capabilities, but given the right tools and employees... Bob From: Bob Camp <kb...@n1k.org> To: pe...@reilley.com; Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Friday, October 28, 2016 2:46 PM Subject: Re: [time-n

Re: [time-nuts] Opening an Isotemp OCXO

ter Reilley" < >> preilley_...@comcast.net> >> To: "Discussion of precise time and frequency measurement" < >> time-nuts@febo.com> >> Sent: Friday, October 28, 2016 3:10 PM >> Subject: Re: [time-nuts] Opening an Isotemp OCXO >> >> &

Re: [time-nuts] Opening an Isotemp OCXO

Hi Roughly 99.9% of all OCXO’s made go to large OEM customers. The percentage may actually be a bit higher than that. There are relatively few markets that “catalog” OCXO’s sell into. Inevitably the first thing that an OEM wants is some form of customization. A specific supply voltage, a

Re: [time-nuts] Opening an Isotemp OCXO

<preilley_...@comcast.net> To: "Discussion of precise time and frequency measurement" <time-nuts@febo.com> Sent: Friday, October 28, 2016 3:10 PM Subject: Re: [time-nuts] Opening an Isotemp OCXO The reason that there was 12 volts on the unit was because I put it there. I

Re: [time-nuts] Opening an Isotemp OCXO

The data sheet for the device only mentions 12V. Other data sheets (eg the 131) mention 5V and 12V, but don't indicate how to specify one or the other. Gerry Sweeny's article at http://gerrysweeney.com/diy-hpagilent-53131a-010-high-stability-timebase-option/ mentions a part number suffix that

Re: [time-nuts] Opening an Isotemp OCXO

I don't know, I looked for a name and could not find one. Sometimes there is no substitute for a big block of copper when soldering. I pick them up at flea markets, no one wants them. I have a few. Pete. On 10/28/2016 12:27 PM, Adrian Godwin wrote: That's one sweet soldering iron. Is it an

Re: [time-nuts] Opening an Isotemp OCXO

The reason that there was 12 volts on the unit was because I put it there. I should have tried 5 volts first but the only datasheet that I could find said 12 volts. All the eBay units that look the same say 12 volts. Pete. On 10/28/2016 12:53 PM, paul swed wrote: I confirmed the pin out

Re: [time-nuts] Opening an Isotemp OCXO

? Joe -Original Message- From: Peter Reilley [mailto:preilley_...@comcast.net] Sent: Friday, October 28, 2016 9:11 AM To: J. L. Trantham Subject: Re: [time-nuts] Opening an Isotemp OCXO Thanks for the link. I did not find any S30 chips that would run off 12 volts. Could the whole OCXO

Re: [time-nuts] Opening an Isotemp OCXO

There is no regulator chip in the unit. I am thinking that this must be a 5 volt unit. Pete. On 10/28/2016 12:42 PM, Dan Rae wrote: On 10/28/2016 9:09 AM, Peter Reilley wrote: The only document that I could find said 12 volt. Pete. The 82 series came in a lot of flavors. I have one 82-49

Re: [time-nuts] Opening an Isotemp OCXO

illey" <preilley_...@comcast.net> To: "Discussion of precise time and frequency measurement" <time-nuts@febo.com> Sent: Friday, October 28, 2016 12:09 PM Subject: Re: [time-nuts] Opening an Isotemp OCXO The only document that I could find said 12 volt. Pete. On 10/28/

Re: [time-nuts] Opening an Isotemp OCXO

I wounder if originally the designer was hoping to use all 8 wire or'd inputs to lower the input referred noise during midscale transition. Then backed out later for some reason. On Fri, Oct 28, 2016 at 1:03 PM, Scott Stobbe wrote: > Could also be a quirk about the

Re: [time-nuts] Opening an Isotemp OCXO

The 1k resistor doesn't seem to feed the 'S30'. It looks as though pin 14 (Vcc) goes via that thick track to the +12 input. On Fri, Oct 28, 2016 at 5:46 PM, jimlux wrote: > On 10/28/16 8:31 AM, Peter Reilley wrote: > > Looking around with my scope it seems that the output

Re: [time-nuts] Opening an Isotemp OCXO

Could also be a quirk about the 74S30 that gives it better phase noise over a basic buffer. On Friday, 28 October 2016, jimlux wrote: > On 10/28/16 9:13 AM, Scott Stobbe wrote: > >> The OCXO82-59 datasheet lists 12V supply, 5V clock out, could also be a >> blown regulator

Re: [time-nuts] Opening an Isotemp OCXO

On 10/28/16 8:31 AM, Peter Reilley wrote: Looking around with my scope it seems that the output driver chip is bad as I expected. It is a TI 14 pin surface mount DIP. It says S30 on it which if it is a 74S30 it is an 8 input positive NAND gate. The board layout confirms this as the 10 MHz

Re: [time-nuts] Opening an Isotemp OCXO

I confirmed the pin out matches a 74s30 also. An S30 is TTL. Great pix to look at. So 12 V on a 5 V chip is indeed a smoker. Find out why there was 12 V. OK crazy talk I see a 1K resistor next to the VCC chip. Would anyone be crazy enough to use a dropping resistor from 12 V to get 5?? Really bad

Re: [time-nuts] Opening an Isotemp OCXO

On 10/28/16 9:13 AM, Scott Stobbe wrote: The OCXO82-59 datasheet lists 12V supply, 5V clock out, could also be a blown regulator in your ocxo, if it is indeed a 12v model. There you go..the design could use a 74S30 as a driver - it's fast, fairly good drive, but runs off 5V. If the regulator

Re: [time-nuts] Opening an Isotemp OCXO

On 10/28/2016 9:09 AM, Peter Reilley wrote: The only document that I could find said 12 volt. Pete. The 82 series came in a lot of flavors. I have one 82-49 which is definitely 12V ( draws 0.12A when warm and maybe 0.3 when cold) and has a 5V pp square wave output at 10 MHz. It also has a

Re: [time-nuts] Opening an Isotemp OCXO

Here is the TI document on "Case Marking." It may not be a 74S30. http://www.ti.com/lit/an/snoa039c/snoa039c.pdf --- Graham == On Fri, Oct 28, 2016 at 11:27 AM, Adrian Godwin wrote: > That's one sweet soldering iron. Is it an American Beauty ? > > > On Fri, Oct 28, 2016

Re: [time-nuts] Opening an Isotemp OCXO

That's one sweet soldering iron. Is it an American Beauty ? On Fri, Oct 28, 2016 at 4:31 PM, Peter Reilley wrote: > I did finally get it open. I used a very large old style soldering > iron and .003 inch steel shim stock. I would melt the solder on the > straight

Re: [time-nuts] Opening an Isotemp OCXO

The OCXO82-59 datasheet lists 12V supply, 5V clock out, could also be a blown regulator in your ocxo, if it is indeed a 12v model. On Friday, 28 October 2016, Poul-Henning Kamp wrote: > > In message <10a3ea7d-37f0-51bc-2470-35645d767...@comcast.net >

Re: [time-nuts] Opening an Isotemp OCXO

The only document that I could find said 12 volt. Pete. On 10/28/2016 11:49 AM, Poul-Henning Kamp wrote: In message <10a3ea7d-37f0-51bc-2470-35645d767...@comcast.net>, Peter Reilley writes: The chip is run off 12 volts so it must be CMOS. Or the OCXO is not a 12V model ?

Re: [time-nuts] Opening an Isotemp OCXO

In message <10a3ea7d-37f0-51bc-2470-35645d767...@comcast.net>, Peter Reilley writes: >The chip is run off 12 volts so it must be CMOS. Or the OCXO is not a 12V model ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD

Re: [time-nuts] Opening an Isotemp OCXO

I did finally get it open. I used a very large old style soldering iron and .003 inch steel shim stock. I would melt the solder on the straight seams and insert small pieces of the shim. Solder does not stick well to steel so the shim kept the soldered seam open. I used a soldering iron

Re: [time-nuts] Opening an Isotemp OCXO

I got one open without too much much trouble with a propane torch. Work fast, use gravity and have something pointy to pry with as you go. -ch 73 de ai6kg On Oct 18, 2016 6:14 AM, "Peter Reilley" wrote: > I bought an Isotemp OCXO82-59 with a frequency of 10 MHz for a

Re: [time-nuts] Opening an Isotemp OCXO

Pete, I'm not familiar with your OCXO but I found one shown on 'theBay' (item 261920574725) and it appeared to have an option for 'mounting screws', four of them, on the bottom. Interestingly, the 'link' to the datasheet for that unit did not show threads for mounting screws. If your unit

Re: [time-nuts] Opening an Isotemp OCXO

Pete Another MIT-er. Well the only way I have handled them is with a small torch. Clamp the unit. Heat the solder and it will flow down to the low point and tend to drip out. Stick a small xacto knife in to break any remaining solder loose. Not super pretty but all of it can be cleaned up usually