Roy, check this: http://www.hparchive.com/Manuals/HP-10811AB-Manual.pdf
Btw. you don't happen to have a spare green pilot lamp lens, do you? That's what my 5065A is missing Regards, Adrian Roy Phillips schrieb: > Jim > I have just found a 10811-60111, and I am wondering if you or another member > have the complete schematic for the unit - mine has the PC board # > 05328-20027, with "fine adjust" pot and C12 &C15 - or is this the normal > format. I have not yet power it up and have noted the advice about > adjustment. > > Thanks > > Roy > > ----- Original Message ----- > From: "Palfreyman, Jim L" <[EMAIL PROTECTED]> > To: "Discussion of precise time and frequency measurement" > <[email protected]> > Sent: Sunday, May 11, 2008 1:18 PM > Subject: Re: [time-nuts] HP/Agilent 5065A Rubidium Vapour frequency standard > problem - fixed > > > >> Thanks folks for all your efforts. >> >> It turns out I was right about the 10811. My replacement 10811 fixed the >> fault but as Chuck pointed out I was being to much of a cowboy with the >> course adjustment. Instead I tuned the course control of the 10811 to a >> reference 5 MHz on the bench and then plugged it all in. This time it >> worked and it stayed working well too! I've been calibrating the C field >> over the last 12 hours. >> >> Now of course I'm turning my attention to the 10811. I would like to fix >> that! >> >> With the heater off, the oscillator behaves well with the course >> adjustment providing the appropriate control (haven't check the EFC yet at >> this temperature). It is of course below 10 MHz. When the heater is >> powered it does the right thing (0.5 amp for a few minutes then drops >> back). The frequency rises to a bit over 10.0000 MHz. However the course >> control no longer has any effect whatsoever. >> >> I'm guessing there are some components in the oscillator circuit that are >> heat damaged after two and a half decades of being in an 82 degree oven. >> I'm going to follow through the manual and see what I can find. >> >> However, if anyone has experienced this pattern before - please let me >> know. >> >> Thanks again for all your help! >> >> Regards, >> >> >> Jim Palfreyman >> >> >> -----Original Message----- >> From: [EMAIL PROTECTED] >> [mailto:[EMAIL PROTECTED] >> Sent: Friday, 9 May 2008 4:00 AM >> To: [email protected] >> Subject: Re: [time-nuts] HP/Agilent 5065A Rubidium Vapour frequency >> standard problem >> >> You didn't really say in your description but you really need to have the >> loop open using the front panel switch before you try to adjust the >> oscillator. Unless you are very familiar with how tiny of a turn it takes >> to make it too far off to lock, you will have it out of range very >> quickly. Open the loop and connect the 5Mhz output to a good frequency >> counter, preferably one that is synched to another rubidium, GPS locked >> crystal or cesium. Once connected, adjust your crystal coarse adjust for >> as close to 5Mhz as possible. If you can't get it below a 0.1 hz error, >> you are going to have trouble getting the unit to lock. Make sure you >> allow a good warm up time for the crystal in the 5065 before you do any >> adjusting. >> If you can get the crystal to that small of an error, then close your loop >> and watch the control meter setting. Typical is that the meter will move a >> small amount but not peg. If it pegs, you have another problem with the >> unit. If it moves a small amount and stops, you can then adjust the coarse >> or fine and bring the meter back to zero. If you use the coarse adjust, at >> this point, you are going to be making VERY tiny adjustments of it. >> Let us know what you find from this and we can move you to the next step. >> Chuck Norton >> >> >> >> >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
