What I noticed is the units seem to want to sync within three discreet values of time ; of the source. I have to press the sync button and watch the output to confirm where its set. I have to press the sync button several times to get the proper value. Attached is a drawing of the test setup.
The data is for two TADD-2 units, I will call them units A & B.Using 10 Mhz input , unit A will either sync to 171 nS, 571 ns or 971 ns. Unit B will sync to 71 nS, 471 nS or 871 ns.
Using 5 Mhz input, unit A will sync 400 ns, 1.200 uS or 2.000 uS. Unit B will sync to 600 nS, 1.400 uS or 2.200 uS.
The Austron 1210 shows 3.5 volts P-P terminated sine waves on the scope for 10 and 5 Mhz, the 1 PPS is +5.8 volts peak, also terminated.
Both TADD-2 were acquired and built less than a month ago - so the parts should be identical values. The only difference is power supply. Unit A runs off my 12 volt system that powers my GPS receivers. Unit B has a 9 volt DC wall wart rated at 0.5A.
I changed the RF Input to my HP5065A and I still see three different values of time; Unit A -102 nS, 698 nS, and 1498 nS. Unit B shows 502 nS, 1302 nS and 2102 nS.
I change to other RF and PPS sources and I see the same problem.My concern is this is repeatable, in my case, and I have to watch the output to get the sync as close to the source, timing wise with the TADD-2. My other dividers, based on async logic do not show this problem. One unit syncs solid at 160 nS on 10 Mhz, the other unit at 210 nS (they were built several years apart and probably different brands of gates).
Brian - KD4FM
TADD2TEST.pdf
Description: Adobe PDF document
_______________________________________________ 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.
