I need to get a HP 54121A Test set repaired. Its trigger input works intermittently

[ks1974In]

I need to get a HP 54121A Test set intended for use with a HP 54120A oscilloscope repaired. There is a problem with the Trigger input-It works intermittently. Does anyone know where I can get it repaired? Or failing that, how I can repair it myself?
Thanks,
Sagar Kapadia

 

[Harald Kapp]

the Trigger input-It works intermittently

Is th eintermittent operation linked to anything you do with the equipment, e.g. when you move the connecting cable or the unit? Intermittent operation is often caused by a bad connection or solder joint. A visual inspection plus tapping against any suspect connections may reveal the culprit. Repair should then be obvious. Open the unit and check internal connections, too, including solder joints on the PCB(s).
Unfortunately there is probably not much more you can do yourself.

Does anyone know where I can get it repaired?

Not me, sorry.

 

[(*steve*)]

There is a full service manual available here. You will have to register (kinda) to download it.

It has everything short of the schematics.

 

[ks1974In]

Is th eintermittent operation linked to anything you do with the equipment, e.g. when you move the connecting cable or the unit? Intermittent operation is often caused by a bad connection or solder joint. A visual inspection plus tapping against any suspect connections may reveal the culprit. Repair should then be obvious. Open the unit and check internal connections, too, including solder joints on the PCB(s).
Unfortunately there is probably not much more you can do yourself.


Not me, sorry.

Thanks Harald

 

[ks1974In]

There is a full service manual available here. You will have to register (kinda) to download it.

It has everything short of the schematics.

Thanks Steve. I downloaded it.

 

[ks1974In]

There is a full service manual available here. You will have to register (kinda) to download it.

It has everything short of the schematics.

The following link contains a document that appears to have the schematics too