[time-nuts] HP 8566B repair YTO Unlock

[David VanHorn]

I finally got work to spring for a nice SA. Based on a recommendation from our EMC guy, I chose an 8566B from Ebay.

Well, less than a week after arrival, it started giving me "YTO Unlock" messages, and in the 0-2GHz band, it would show a 100 mhz carrier at 1.53 GHz (more or less)
After a bit of nosing around, I isolated the failure to a 0.33uF 100V large polyester(?) cap on the A19 board that bypasses an 8.2V zener making the 10V reference.
The cap read 33 ohms.  I replaced it with a pair of 0.15uF 630V polyester caps that I happened to have, and it's all up and running nicely now.

Just posting in case it becomes useful for someone else.