Re: [time-nuts] Need Austron 2110 manual
Hi Skip; I think I have a 2110A manual if you can't find one let me know. I purpose I would drop it at a FedEx Kinkos where they could copy it and ship the copy to you. You could pay them directly by credit card. Be aware this could end up expensive I think this manual has fold out pages, and other things that require hand placement. Best Wishes; Thomas Knox NIST 4475 Whitney Place Boulder Colorado 80305 1-303-554-0307 tomk...@nist.gov Quoting Chuck Harris cfhar...@erols.com: Try PRC68.com Skip Withrow wrote: Hello Time-Nuts, I am in need of a manual for the Austron 2110 Disciplined Frequency Standard. Anyone have an electronic copy? I have already tried KO4BB's site and BAMA. I would be more than happy to pay shipping so that I could copy/scan a hard-copy if you have one. Guaranteed to be returned promptly. Regards, Skip Withrow ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Need Austron 2110 manual
Tom, You might inquire of Brooke Clark whether or not he has a copy. He does provide a CD of a number of Austron models. Brooke Clarke http://www.prc68.com Tom Linbeck -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of tomk...@nist.gov Sent: Wednesday, May 27, 2009 12:27 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Need Austron 2110 manual Hi Skip; I think I have a 2110A manual if you can't find one let me know. I purpose I would drop it at a FedEx Kinkos where they could copy it and ship the copy to you. You could pay them directly by credit card. Be aware this could end up expensive I think this manual has fold out pages, and other things that require hand placement. Best Wishes; Thomas Knox NIST 4475 Whitney Place Boulder Colorado 80305 1-303-554-0307 tomk...@nist.gov Quoting Chuck Harris cfhar...@erols.com: Try PRC68.com Skip Withrow wrote: Hello Time-Nuts, I am in need of a manual for the Austron 2110 Disciplined Frequency Standard. Anyone have an electronic copy? I have already tried KO4BB's site and BAMA. I would be more than happy to pay shipping so that I could copy/scan a hard-copy if you have one. Guaranteed to be returned promptly. Regards, Skip Withrow ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Need Austron 2110 manual
The copy of Brooke Clarke's CD I have has the 2110B manual. Stanley - Original Message From: Thomas Linbeck tlinb...@sbcglobal.net To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Wednesday, May 27, 2009 12:54:59 PM Subject: Re: [time-nuts] Need Austron 2110 manual Tom, You might inquire of Brooke Clark whether or not he has a copy. He does provide a CD of a number of Austron models. Brooke Clarke http://www.prc68.com Tom Linbeck -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of tomk...@nist.gov Sent: Wednesday, May 27, 2009 12:27 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Need Austron 2110 manual Hi Skip; I think I have a 2110A manual if you can't find one let me know. I purpose I would drop it at a FedEx Kinkos where they could copy it and ship the copy to you. You could pay them directly by credit card. Be aware this could end up expensive I think this manual has fold out pages, and other things that require hand placement. Best Wishes; Thomas Knox NIST 4475 Whitney Place Boulder Colorado 80305 1-303-554-0307 tomk...@nist.gov Quoting Chuck Harris cfhar...@erols.com: Try PRC68.com Skip Withrow wrote: Hello Time-Nuts, I am in need of a manual for the Austron 2110 Disciplined Frequency Standard. Anyone have an electronic copy? I have already tried KO4BB's site and BAMA. I would be more than happy to pay shipping so that I could copy/scan a hard-copy if you have one. Guaranteed to be returned promptly. Regards, Skip Withrow ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Need Austron 2110 manual
oops that should be 2010B on the CD Sorry Stanley - Original Message From: Stanley Reynolds stanley_reyno...@yahoo.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Wednesday, May 27, 2009 1:59:26 PM Subject: Re: [time-nuts] Need Austron 2110 manual The copy of Brooke Clarke's CD I have has the 2110B manual. Stanley - Original Message From: Thomas Linbeck tlinb...@sbcglobal.net To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Wednesday, May 27, 2009 12:54:59 PM Subject: Re: [time-nuts] Need Austron 2110 manual Tom, You might inquire of Brooke Clark whether or not he has a copy. He does provide a CD of a number of Austron models. Brooke Clarke http://www.prc68.com Tom Linbeck -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of tomk...@nist.gov Sent: Wednesday, May 27, 2009 12:27 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Need Austron 2110 manual Hi Skip; I think I have a 2110A manual if you can't find one let me know. I purpose I would drop it at a FedEx Kinkos where they could copy it and ship the copy to you. You could pay them directly by credit card. Be aware this could end up expensive I think this manual has fold out pages, and other things that require hand placement. Best Wishes; Thomas Knox NIST 4475 Whitney Place Boulder Colorado 80305 1-303-554-0307 tomk...@nist.gov Quoting Chuck Harris cfhar...@erols.com: Try PRC68.com Skip Withrow wrote: Hello Time-Nuts, I am in need of a manual for the Austron 2110 Disciplined Frequency Standard. Anyone have an electronic copy? I have already tried KO4BB's site and BAMA. I would be more than happy to pay shipping so that I could copy/scan a hard-copy if you have one. Guaranteed to be returned promptly. Regards, Skip Withrow ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Need Austron 2110 manual
I think I have one and did lend it out recently. I would be glad to ship it to you but I am in Europe and will not be back till the 12th of June. Check recent dialog on t-n I thing the person I lend it to did do a digital copy. If every thing else fails wait for three weeks. Bert -Original Message- From: tomk...@nist.gov To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Wed, 27 May 2009 1:27 pm Subject: Re: [time-nuts] Need Austron 2110 manual Hi Skip;? I think I have a 2110A manual if you can't find one let me know.? I purpose I would drop it at a FedEx Kinkos where they could copy it and ship the copy to you.? You could pay them directly by credit card. Be aware this could end up expensive? I think this manual has fold out pages, and other things that require hand placement.? Best Wishes;? Thomas Knox? NIST? 4475 Whitney Place? Boulder Colorado 80305? 1-303-554-0307? tomk...@nist.gov? ? ? Quoting Chuck Harris cfhar...@erols.com:? ? Try PRC68.com? ? Skip Withrow wrote:? Hello Time-Nuts,? ? I am in need of a manual for the Austron 2110 Disciplined Frequency? Standard. Anyone have an electronic copy? I have already tried KO4BB's? site and BAMA.? ? I would be more than happy to pay shipping so that I could copy/scan a? hard-copy if you have one. Guaranteed to be returned promptly.? ? Regards,? Skip Withrow? ? ___? time-nuts mailing list -- time-n...@febo.com? To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts? and follow the instructions there.? ? ? ___? time-nuts mailing list -- time-n...@febo.com? To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts? and follow the instructions there.? ? ? ? ___? time-nuts mailing list -- time-n...@febo.com? To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts? and follow the instructions there.? ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] HP 3320B manual
Fellow time-nuts, Does anyone just happends to have a HP 3320B operations and service manual lying around? I got a unit and wants to become more familiar with it. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] FE 5680A supply voltage
Is anyone familiar with the hazards of an undervoltage supply on an FE 5680A? I've seen reports of users running it at a more commonly available 13.2V instead of 15V. What module might be most affected? The lamp? Thanks, Leigh. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] HP 3320B manual
PDF here : hxxp://www.hparchive.com/Manuals/HP-3320AB-Manual.pdf (change xx to tt). Stanley - Original Message From: Magnus Danielson mag...@rubidium.dyndns.org To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Wednesday, May 27, 2009 4:54:51 PM Subject: [time-nuts] HP 3320B manual Fellow time-nuts, Does anyone just happends to have a HP 3320B operations and service manual lying around? I got a unit and wants to become more familiar with it. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] FE 5680A supply voltage
The FEI units use two paralleled low dropout regulators to drop the 15V input voltage down to 14V. There is also a series protection diode that drops some more voltage. Combined you need at least 14.7V input. Anything less and the regulators will not regulate and the unit will not work within spec. Anything much more than 15V and the regulators will overheat (you can supposedly go to 18V, but I would not do it without lots of cooling). _ Windows Live™: Keep your life in sync. http://windowslive.com/explore?ocid=TXT_TAGLM_BR_life_in_synch_052009 ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] PCI IRIG receiver card for AIX?
Does anybody know of any PCI cards that will receive IRIG-B time signals and come with an I/O driver for AIX (IBM's flavor of UNIX)? Industrial-grade commercial products are preferred. Thanks, Joe Gwinn ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] PCI IRIG receiver card for AIX?
Does anybody know of any PCI cards that will receive IRIG-B time signals and come with an I/O driver for AIX (IBM's flavor of UNIX)? Industrial-grade commercial products are preferred. In the past I have, on one occasion, been able to use a regular audio card for this, and I used the IRIG_AUDIO refclock with ntpd for this. I don't know if that is what you have in mind but it should be an option. H ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] PCI IRIG receiver card for AIX?
Symmetricom bc635pci-V2 or -U? PCI-SG 2U (some of the old TrueTime products, I'm sure) It does IRIG... You'll have to call Symmetricom to see about drivers.. It has Win, Linux, and Solaris. On 5/27/09 7:26 PM, Joe Gwinn joegw...@comcast.net wrote: Does anybody know of any PCI cards that will receive IRIG-B time signals and come with an I/O driver for AIX (IBM's flavor of UNIX)? Industrial-grade commercial products are preferred. Thanks, Joe Gwinn ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Broken Ovenaire OSC 85-50
Bruce, Thanks for your analysis. Is this all in your head or do you use a computer program? If I understand correctly, you are using the term 'buffer' to describe what I call the 'Output Board'. If so, then the Output Board seems to be doing what it is supposed to do and the problem is a low output from the Oscillator Board. Any thoughts as to the cause of the low output? Capacitors changing value, resistors changing value, inductors changing value (by the way, I need a refresher on how to read the color code of inductors), transistors loosing gain? I have not measured the temperature but the crystal has '79 C' written on it. The capacitors appear to be dipped silvered mica and the resistors appear to be carbon. I can send a picture of both boards if that would help. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Bruce Griffiths Sent: Tuesday, May 26, 2009 10:43 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Broken Ovenaire OSC 85-50 Joe A quick analysis if the buffer indicates that the gain with a 50 ohm load is about 1x. The gain into a 1M load should be about 4x. Simulating the output stage indicates that the maximum output achievable is about 1.6V pp into 1M or 0.4Vpp into 50 ohms. However distortion is a bit high. This requires about 0.4Vpp at the input to the buffer. The dc level on the red wire is reasonably consistent with quick simulation of the level without oscillation at an oven temperature of 90-100C. When oscillating the current drawn by the oscillator may increase slightly, bringing the value closer to that observed. Bruce J. L. Trantham wrote: Well, a little work with a scalpel and a small flat bladed screw driver and I was able to open the package. Inside is what I call an 'Output Board' that contains the output circuit and the 'FINE' frequency adjust along with the 'Oven' which has the 'COARSE' frequency adjust. Attached to the 'Oven' is what I call the 'Oven Controller Board'. With the removal of 3 screws and the 'nut' on the 'COARSE' frequency adjust, the 'Oscillator Board' can be removed. I have 'derived' the schematic from inspections of the 'Output Board' and the 'Oscillator Board'. I made no attempt at the 'Oven Controller Board' since it seems to be operating ok. More on this below. I have attached the schematics of the output board and oscillator boards. I made some measurements of DC and RF voltages on the output board. I have multiple pictures that are too large to attach. If anyone would like to see these, I can send them. At start up, the 85-50 draws about 0.5A then falls to about 0.25A as the 'oven' heats up suggesting the temperature regulator circuit is functional. The 'COARSE' and 'FINE' frequency adjusts work and the frequency can be brought spot on as compared to my GPSDO. I have ordered new transistors in the hope that these are the problem. I am a little puzzled by the drop in voltage at the 'Red' wire to the oven. It serves both the 'Oscillator Board' and the 'Oven Controller Board'. 2.5 VDC seems a little low for the oscillator. Also, the gain of the output stage of the output board seems a little low. 0.1 V P-P goes to 0.36 V P-P. I have a second, good, 85-50 but would like to avoid opening it if possible. Any help would be appreciated. I hope I made no mistakes on the schematics. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Gordon Batey Sent: Sunday, May 24, 2009 6:50 PM To: time-nuts@febo.com Subject: Re: [time-nuts] Broken Ovenaire OSC 85-50 I had an earlier model 20 mhx ovenaire osc that had very low output. I opened it up with a scalpel and found the TTL chip had failed and was only letting a small amount of the osc signal thru. I was able to use an external TTl (74LS20 I think) to restore it. As I recall I was unable to readily get to the chip so I replaced it with an external one. Good luck. Gordon ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Broken Ovenaire OSC 85-50
Bruce, I sent you two pictures directly. I hope I did not choke your inbox. They were a total of about 6 MB. If so, I can probably reduce the quality and get a smaller file. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Bruce Griffiths Sent: Wednesday, May 27, 2009 11:03 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Broken Ovenaire OSC 85-50 Joe Low output can be caused by a high impedance path, an open circuit component, an open solder joint, a low value cap, low gain transistor, etc. The oscillator limits by either saturating or better cutting off the oscillator transistor (would need to check to see which but its more likely to be the latter). If oscillator transistor cutoff is the limiting mechanism then too low transistor collector current could be one cause. Bruce J. L. Trantham wrote: Bruce, Thanks for your analysis. Is this all in your head or do you use a computer program? Both. I used LTSpice to check. If I understand correctly, you are using the term 'buffer' to describe what I call the 'Output Board'. Yes. If so, then the Output Board seems to be doing what it is supposed to do and the problem is a low output from the Oscillator Board. Any thoughts as to the cause of the low output? Capacitors changing value, resistors changing value, inductors changing value (by the way, I need a refresher on how to read the color code of inductors), transistors loosing gain? I have not measured the temperature but the crystal has '79 C' written on it. The capacitors appear to be dipped silvered mica and the resistors appear to be carbon. I can send a picture of both boards if that would help. Yes that may help. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Bruce Griffiths Sent: Tuesday, May 26, 2009 10:43 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Broken Ovenaire OSC 85-50 Joe A quick analysis if the buffer indicates that the gain with a 50 ohm load is about 1x. The gain into a 1M load should be about 4x. Simulating the output stage indicates that the maximum output achievable is about 1.6V pp into 1M or 0.4Vpp into 50 ohms. However distortion is a bit high. This requires about 0.4Vpp at the input to the buffer. The dc level on the red wire is reasonably consistent with quick simulation of the level without oscillation at an oven temperature of 90-100C. When oscillating the current drawn by the oscillator may increase slightly, bringing the value closer to that observed. Bruce J. L. Trantham wrote: Well, a little work with a scalpel and a small flat bladed screw driver and I was able to open the package. Inside is what I call an 'Output Board' that contains the output circuit and the 'FINE' frequency adjust along with the 'Oven' which has the 'COARSE' frequency adjust. Attached to the 'Oven' is what I call the 'Oven Controller Board'. With the removal of 3 screws and the 'nut' on the 'COARSE' frequency adjust, the 'Oscillator Board' can be removed. I have 'derived' the schematic from inspections of the 'Output Board' and the 'Oscillator Board'. I made no attempt at the 'Oven Controller Board' since it seems to be operating ok. More on this below. I have attached the schematics of the output board and oscillator boards. I made some measurements of DC and RF voltages on the output board. I have multiple pictures that are too large to attach. If anyone would like to see these, I can send them. At start up, the 85-50 draws about 0.5A then falls to about 0.25A as the 'oven' heats up suggesting the temperature regulator circuit is functional. The 'COARSE' and 'FINE' frequency adjusts work and the frequency can be brought spot on as compared to my GPSDO. I have ordered new transistors in the hope that these are the problem. I am a little puzzled by the drop in voltage at the 'Red' wire to the oven. It serves both the 'Oscillator Board' and the 'Oven Controller Board'. 2.5 VDC seems a little low for the oscillator. Also, the gain of the output stage of the output board seems a little low. 0.1 V P-P goes to 0.36 V P-P. I have a second, good, 85-50 but would like to avoid opening it if possible. Any help would be appreciated. I hope I made no mistakes on the schematics. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Gordon Batey Sent: Sunday, May 24, 2009 6:50 PM To: time-nuts@febo.com Subject: Re: [time-nuts] Broken Ovenaire OSC 85-50 I had an earlier model 20 mhx ovenaire osc that had very low output. I opened it up with a scalpel and found the TTL chip had failed and was only letting a small amount
Re: [time-nuts] Broken Ovenaire OSC 85-50
Joe In box is fine, 6MB is relatively small and not a problem. The brown caps look like they might be silver mica. It may be worth resoldering all the solder joints on these caps as they can sometimes go high impedance over time. The ceramic caps marked 103 are 10,000pF = 10nF = 0.01uF. If you have a current probe and oscilloscope it would be useful to look at the RF current flowing in the crystal, oscillator transistor etc. Bruce J. L. Trantham wrote: Bruce, I sent you two pictures directly. I hope I did not choke your inbox. They were a total of about 6 MB. If so, I can probably reduce the quality and get a smaller file. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Bruce Griffiths Sent: Wednesday, May 27, 2009 11:03 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Broken Ovenaire OSC 85-50 Joe Low output can be caused by a high impedance path, an open circuit component, an open solder joint, a low value cap, low gain transistor, etc. The oscillator limits by either saturating or better cutting off the oscillator transistor (would need to check to see which but its more likely to be the latter). If oscillator transistor cutoff is the limiting mechanism then too low transistor collector current could be one cause. Bruce J. L. Trantham wrote: Bruce, Thanks for your analysis. Is this all in your head or do you use a computer program? Both. I used LTSpice to check. If I understand correctly, you are using the term 'buffer' to describe what I call the 'Output Board'. Yes. If so, then the Output Board seems to be doing what it is supposed to do and the problem is a low output from the Oscillator Board. Any thoughts as to the cause of the low output? Capacitors changing value, resistors changing value, inductors changing value (by the way, I need a refresher on how to read the color code of inductors), transistors loosing gain? I have not measured the temperature but the crystal has '79 C' written on it. The capacitors appear to be dipped silvered mica and the resistors appear to be carbon. I can send a picture of both boards if that would help. Yes that may help. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Bruce Griffiths Sent: Tuesday, May 26, 2009 10:43 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Broken Ovenaire OSC 85-50 Joe A quick analysis if the buffer indicates that the gain with a 50 ohm load is about 1x. The gain into a 1M load should be about 4x. Simulating the output stage indicates that the maximum output achievable is about 1.6V pp into 1M or 0.4Vpp into 50 ohms. However distortion is a bit high. This requires about 0.4Vpp at the input to the buffer. The dc level on the red wire is reasonably consistent with quick simulation of the level without oscillation at an oven temperature of 90-100C. When oscillating the current drawn by the oscillator may increase slightly, bringing the value closer to that observed. Bruce J. L. Trantham wrote: Well, a little work with a scalpel and a small flat bladed screw driver and I was able to open the package. Inside is what I call an 'Output Board' that contains the output circuit and the 'FINE' frequency adjust along with the 'Oven' which has the 'COARSE' frequency adjust. Attached to the 'Oven' is what I call the 'Oven Controller Board'. With the removal of 3 screws and the 'nut' on the 'COARSE' frequency adjust, the 'Oscillator Board' can be removed. I have 'derived' the schematic from inspections of the 'Output Board' and the 'Oscillator Board'. I made no attempt at the 'Oven Controller Board' since it seems to be operating ok. More on this below. I have attached the schematics of the output board and oscillator boards. I made some measurements of DC and RF voltages on the output board. I have multiple pictures that are too large to attach. If anyone would like to see these, I can send them. At start up, the 85-50 draws about 0.5A then falls to about 0.25A as the 'oven' heats up suggesting the temperature regulator circuit is functional. The 'COARSE' and 'FINE' frequency adjusts work and the frequency can be brought spot on as compared to my GPSDO. I have ordered new transistors in the hope that these are the problem. I am a little puzzled by the drop in voltage at the 'Red' wire to the oven. It serves both the 'Oscillator Board' and the 'Oven Controller Board'. 2.5 VDC seems a little low for the oscillator. Also, the gain of
