Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: TerryD on October 29, 2014, 11:31:32 am

Title: Intermittant Crapping Out of Tube sockets/Tubes???
Post by: TerryD on October 29, 2014, 11:31:32 am

I can't stand it.  My Vibrolux keeps crapping out on me.  It seems like it's in the phase inverter AT7 or the AX7 right next to it.  When it craps out I jiggle one of those vigorously to get it back running.
I Have:
Swapped the AT7 for another ....still the same problem
Cleaned out the sockets with caig deoxit...still the same problem
Tightened the sockets, twice...still the same problem
Run the amp with the chassis on the outside of the cabinet..seems to run fine!!  Fluke?
Ran with the chassis in the cabinet with the full metal tube retainers (which I hate)...still the same problem
 
Would appreciate any help.
Thanks,
Terry
 

Title: Re: Intermittant Crapping Out of Tube sockets/Tubes???
Post by: John on October 29, 2014, 11:35:41 am

I would then try wiggling the wires coming off the sockets, and also look at all close by solder joints with a strong magnifying glass. It sounds like you're making contact when you wiggle the tubes around.


Of course, if it's a PCB then this idea is totally wrong.  :icon_biggrin:

Title: Re: Intermittant Crapping Out of Tube sockets/Tubes???
Post by: shooter on October 29, 2014, 12:28:34 pm

can you "break it" the same way?  If so, you might be able to gator-clip your meter/scope to the tube pins and "see" if something drops out, or while broke what's missing. 

Title: Re: Intermittant Crapping Out of Tube sockets/Tubes???
Post by: andyfromdenver on October 29, 2014, 02:03:30 pm

If it's vintage, the sockets may just be worn out, so even tightening is ineffective.
Especially if it works sitting on the bench upright or something.

Title: Re: Intermittant Crapping Out of Tube sockets/Tubes???
Post by: TerryD on October 29, 2014, 03:27:01 pm

It's a 66 vibrolux