I'm in the process of restoring a HP 2909A digital clock. This is a Nixie clock that displays the time on the front, and has multiple time coded outputs on the back. I have the documentation for the Dymec 2509A but the schematic doesn't match my unit. The problem with the clock is that several times a day the clock skips seconds and so appears to run fast. This happens when it is using the 60hz line current as the time base, or an external 1PPS. If anyone has a 2509A that they can part with (working or not), or if you have extra cards that you no longer need, I'd be happy to purchase an entire unit or a partial unit, or just one card. The card I'm looking for is 5060-6217 the second from the left looking from the front. Thank you. Regards, Mitch