); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] Tom,
I was last involved with a 3336A about 12 years ago, so I hope I can still remember the correct situation (but no guarantee). As I remember it, there are some relays in that aluminum box between the circuit board and the front panel 75, 135 and 600 ohm outputs. If you have the older, tall, yellow plastic relays in there, then those relays might be your problem -- they were not reliable over time. But if you have the newer, black low-profile Omron relays, then you've got good relays (that are far less likely to fail). Given your symptom, I'd guess you have the older, tall, yellow plastic relays. If I remember correctly, that version relay clips to the PCB and its gold leaf contacts actually touch pads on the PCB -- so the PCB itself becomes part of the relay action. The newer, black Omron relays are potted, completely self-contained, and are soldered into a re-designed board. BTW, if your unit has the option 005 precision attenuator, then the precision attenuator is an aluminum cast base, with solenoids on top (and a removeable cover for access to the solenoids) and a factory-only-repairable main channel milled-into the aluminum base, with the attenuator pads in the form of laser-etched substrate pads that fit into the channel. ...The solenoids push various gold-plated leaf contacts against the small contact pads on the substrate pads. Best, Greg ----- Original Message ----- From: "Tom Clifton" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Monday, July 16, 2007 1:16 PM Subject: [time-nuts] HP-3336A Manual I perused the pdf manual and came up more confused than when I started... My problem seems to be in the Option 005 high precision attenuator (as I can best tell). There is an aluminum box between the circuit board and the front panel 75 ohm, 135 ohm and 600 ohm outputs. That mysterious 'box' seems to be open. I'm not sure if it is just an impedence matching assembly, or if it includes the option 005. As the front panel level control is changed, the raw 50 ohm board output measures between +5 and -5 dbm and every time the display crosses a -3dbm threshold (-3, -13, -23 etc) you hear a relay click and the raw output jumps back up 10db. Hope that clarifies more than confuses... _______________________________________________ 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.
