https://www.febo.com/pipermail/time-nuts/2017-April/104600.html
We did our first Zeeman frequency test on our good cesium 05061-6077 Tube with a 1 Meg scope probe and a 11 Meg Digital Voltmeter in parallel. KB7APQ used his digital generator for the variable frequency. See paragraph 3-16 on page 3-8. At 53.53 kc the level peaked at 3 V peak to peak which is close to the theoretical 1 V rms. I didn't have a program readily available to do a graph but you can see the main and upper and lower adjacent peaks. We can compare with Figure 4-43 (page 4-31) in the service manual for the HP5061B if anyone can graph this. We had the C field control at the factory setting of 453. Our actual maximum on main peak was 53.657 kc not 53.530 kc. We got 53.530 kc with a slightly different new C field setting of 463. Factor spec is within 100 cps and we were 127 cps off. This is probably not a bad drift for a 30 year old instrument. https://www.febo.com/pipermail/time-nuts/2017-April/104600.html kc beam (C Field set at 453) 55.03 27 54.93 27 54.83 27 54.73 28 54.63 30 54.53 32 54.43 33 54.33 31 54.23 28 54.13 25 54.03 22 53.93 22 53.83 24 53.73 29 53.63 35 53.53 32 53.43 39 53.33 34 53.23 28 53.13 24 53.03 22 52.93 23 52.83 25 52.73 28 52.63 31 52.53 32 52.43 31 52.33 29 52.23 27 52.13 27 52.03 26 We suspect a bad beam tube on our second instrument and therefore wanted to practice the Low Frequency Coil test on our known good beam tube. It allows the performance of the tube to be checked with no rf drive. See paragraph 5-175 (page 5-22) We used 26.765 kc and it also peaked out at 3 V pp. I discovered that this is half of the Zeeman frequency but it is not clear why this is so. We obtained a beam current of 23 with rf drive removed from the tube by pulling P2 on A4A1. I spoke to Corby Dawson last night. Among many things, he reported that you will be able to get 80% to 90% of this beam current in normal lock mode. We are getting 87% or 20. πθ°μΩω±√·Γλ WB0KVV _______________________________________________ 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.
