Re: [time-nuts] Schematic for the 'analog' section of an FE-5680A?

2013-12-14 Thread Jamieson (Jim) Rowe
Hi Bob, Thanks for that tip. I have tweaked C217 a bit already, but I'll try again in the hope that it'll finally do the trick. By the way, which is the correct direction to push the frequency up a tad -- clockwise or anticlockwise? I think I tried antclockwise the first time... All the

Re: [time-nuts] Schematic for the 'analog' section of an FE-5680A?

2013-12-14 Thread Jamieson (Jim) Rowe
Hi Bert, Thank you too for your tips and suggestions. I thought there might be 'some' analog circuitry in the 5680A, because the photodetector output from the 'far end' of the Rb resonance cavity probably needs some amplification, before its 'strong enough' to be fed into an A-to-D converter.

Re: [time-nuts] Schematic for the 'analog' section of an FE-5680A?

2013-12-14 Thread Jamieson (Jim) Rowe
Hi Paul, Thanks for those helpful comments. You have certainly pointed me in the right directions, I suspect. Best wishes for the Festive Season. Jim Rowe -Original Message- From: paul swed Sent: Friday, December 13, 2013 10:10 AM To: Discussion of precise time and frequency

Re: [time-nuts] Schematic for the 'analog' section of an FE-5680A?

2013-12-14 Thread Bob Camp
Hi If I remember it’s a half turn trimmer. The “right” direction will depend on where they left it … If it’s multi turn then the answer is counterclockwise. Best to simply watch the result on a counter. Bob On Dec 14, 2013, at 4:09 PM, Jamieson (Jim) Rowe jimr...@optusnet.com.au wrote:

Re: [time-nuts] Schematic for the 'analog' section of an FE-5680A?

2013-12-14 Thread ewkehren
One thing you also should do is set the tuning, even if it sweeps through 10 MHz if outside the lock range it will not lock. I have seen it. Bert Sent from Samsung tabletJamieson (Jim) Rowe jimr...@optusnet.com.au wrote:Hi Bert, Thank you too for your tips and suggestions. I thought there

Re: [time-nuts] time-nuts Digest, Vol 113, Issue 34

2013-12-14 Thread Stan
Hi Corby, My 5065A is s/n 2816A01565 so technically I don't meet the conditions of your query, but I'm still curious what it is that you're looking for! Regards, Stan - Well it's that time again to ask HP 5065A owners if they have early or late SN units.

Re: [time-nuts] Schematic for the 'analog' section of an FE-5680A?

2013-12-14 Thread EB4APL
Jim, I also found my notes for other unit. It sweeps from 9.9997414 to 10.493 and also locks in 3 minutes. Regards, Ignacio EB4APL On 15/12/2013 2:26, EB4APL wrote: Jim, My unit, according to my notes, sweeps between 9.999766 MHz and 10.56 MHz and locks in 3 minutes from cold

Re: [time-nuts] Schematic for the 'analog' section of an FE-5680A?

2013-12-14 Thread EB4APL
Jim, My unit, according to my notes, sweeps between 9.999766 MHz and 10.56 MHz and locks in 3 minutes from cold start. Maybe you have to move the frequency a bit towards the low side. Regards, Ignacio EB4APL On 15/12/2013 0:27, ewkehren wrote: One thing you also should do is set the