Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Doc58 on January 12, 2013, 03:46:57 pm

Title: How do I check the Coupling Caps on a Super Reverb?
Post by: Doc58 on January 12, 2013, 03:46:57 pm

Folks,
  I'd like to know how I check the Coupling Caps on a 67' Super Reverb (Correctly)
Any Advice here of the Forum? Thanks!   Doc

Title: Re: How do I check the Coupling Caps on a Super Reverb?
Post by: tubenit on January 12, 2013, 05:59:46 pm

Here is a thread on that:

http://www.el34world.com/Forum/index.php?topic=9391.0 (http://www.el34world.com/Forum/index.php?topic=9391.0)

With respect, Tubenit

I used the SEARCH function to find that.

It is also covered somewhere in Hoffman's Library of Information

Title: Re: How do I check the Coupling Caps on a Super Reverb?
Post by: HotBluePlates on January 13, 2013, 12:14:25 am

Fastest way is to measure dc voltages on all tube pins and compare to the schematic.

If they're close, then the caps are probably good. Due to today's higher wall voltage, expect measured voltages to be higher than the schematic.

If you get d.c. voltage on any grid other than the phase inverter, then you probably have leaking caps.

Title: Re: How do I check the Coupling Caps on a Super Reverb?
Post by: stratele52 on January 13, 2013, 04:06:31 am

Read voltage each side of the cap , from ground. Disconect the end of the cap with the lower reading . Read voltage at this end, if more than 1/2 volts caps is leaky.