Re: [time-nuts] HP10811 dual oven
Hi Dan, I would be interested on that document too Thank you in advance 73 KJ6UHN Alex On 8/3/2015 12:40 PM, Dan Kemppainen wrote: Hi, If you search the internet, you should come across a design by Warren S. It's basically the same type of oven controller that is used in the internal oven for that oscillator. I did a surface mount version of his design a while back. I've been running it for quite a while now. IMO it is helping to reduce the thermal drift of the oscillator. Bob has pointed out in the past that the outer oven was not intended to be active all of the time. This is probably true. That said it seems to help in my setup. If you are unable to find the documentation, please let me know. I can try to dig it up when I get home. Dan On 8/3/2015 12:00 PM, time-nuts-requ...@febo.com wrote: Hi The “external” heater on the Z3801 OCXO is only needed if you are regularly running below -20C in your environment. Other than the alarm signal, there is no harm in letting it simply shut off forever. Bob >On Aug 2, 2015, at 8:56 AM,tim...@timeok.it wrote: > > >Hi, >I have seen, but I do not remember where, someone have rebuilt the external oven controller to complete a stand alone OCXO removed from an HPZ3801A. >Can you hep me to find the document? > >Luciano >timeok ___ 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] Speaking of HP5065 repair/improvement
I recently bought myself a HP5065 and after I replaced the OCXO with one from my defunct 5061, it seems to be humming along nicely: 4e-13 out to about tau=60k so far. Next experiment is to calibrate/tune it according to the manual and see if that helps anything. My reason to buy it was three-fold. I need a free-running house-standard for the NTP stuff I'm doing, I wanted an electronics project to justify having bought AOE3, and finally Corbys "Super" modification and various peoples measurements show there is unrealized potential in the physics package. My unit is series 940, which means that it uses stuff like outdated uA702 op-amps etc, that leaves quite a room for improvement. At the far end of my journey, is an experiment where I drive the physics package with entirely new electronics: A DDS for the 60MHz, an ADC on the "solar cell", a DAC on the C-field and an ARM CPU to do steer it all. (I might leave the temp-controller behind). But to begin with I'm just going to do some of the upgrades I can see in the newer version of the manual, for the sheer fun of it and just to see how much they improve the performance. For instance the A9 Integrator goes from a uA702 to a OPA111BM - that's unlikely to hurt the performance... This is not going to be a particularly fast project, but any insights, wisdom, data og participation is most welcome. Poul-Henning PS: I want to stress that I am not going to compete with Corby: I won't fix or tune your 5065 for you. If you want your 5065 in competent hands, send it to Corby. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ 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] Symmetricom® TS2100-GPS update and conversion
Gregory Beat kirjoitti: I removed the Trimble ACE III receiver (39818-C), but noted that this specific unit had a "widget board" (65398.69) on the SMA antenna connector and 2 wires (DC power) to the 3-pin header on the main board. Was this board used to support +12 VDC powered outdoor antennas? It's antenna biasing circuit, includes 5V regulator to create bias for antenna. It's not needed with Heol N024 anymore, N024 feeds the needed bias itself. Best regards, -- 73s! Esa OH4KJU ___ 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] HP10811 dual oven
Hi, If you search the internet, you should come across a design by Warren S. It's basically the same type of oven controller that is used in the internal oven for that oscillator. I did a surface mount version of his design a while back. I've been running it for quite a while now. IMO it is helping to reduce the thermal drift of the oscillator. Bob has pointed out in the past that the outer oven was not intended to be active all of the time. This is probably true. That said it seems to help in my setup. If you are unable to find the documentation, please let me know. I can try to dig it up when I get home. Dan On 8/3/2015 12:00 PM, time-nuts-requ...@febo.com wrote: Hi The “external” heater on the Z3801 OCXO is only needed if you are regularly running below -20C in your environment. Other than the alarm signal, there is no harm in letting it simply shut off forever. Bob >On Aug 2, 2015, at 8:56 AM,tim...@timeok.it wrote: > > >Hi, >I have seen, but I do not remember where, someone have rebuilt the external oven controller to complete a stand alone OCXO removed from an HPZ3801A. >Can you hep me to find the document? > >Luciano >timeok ___ 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] Lamp oven repair info for HP 5065A
The 3 units I have repaired had the original heater wire twisted with around 7 twists per inch. That's what new windings replicated. The teflon insulated wire and the Kapton tape should prevent any further problem! Corby ___ 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.
