Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: spunko on February 17, 2022, 02:06:57 pm

Title: Fender Hot Rod Deville - Recap - not sure of voltage readings
Post by: spunko on February 17, 2022, 02:06:57 pm
Hello there, I have recaped hot rod deluxes but never a deville, which uses 2 more filter caps.
The amp  with the new caps works great, sounds great, bias great and the voltage readings I usually check all seem ok, except for the 2 addional caps that the deville uses, and I don't know if its ok or not.

I have the amp plugged into a bulb limiter, so the voltages are a bit low compared to the schematic.
The schematic doesn't show the voltages on each specific cap, only TP points, and my readings are ok versus those TPs

This is just a simple recap, because the IC caps were leaking material. F&T's are in place now.

Are these readings ok? (green dots)
Am i missing something?

(https://i.imgur.com/phwYV4P.png)
Title: Re: Fender Hot Rod Deville - Recap - not sure of voltage readings
Post by: sluckey on February 17, 2022, 02:15:57 pm
Those readings are fine.
Title: Re: Fender Hot Rod Deville - Recap - not sure of voltage readings
Post by: PRR on February 17, 2022, 07:40:49 pm
....The schematic doesn't show the voltages on each specific cap, only TP points....

https://www.google.com/search?q=fender+hot+rod+deville+schematic
https://www.thetubestore.com/lib/thetubestore/schematics/Fender/Fender-Hot-Rod-Deville-Schematic.pdf
(You may already have this, but not the first page?)

Those caps are bottom-center of page 1. Cap numbers are on the schematic and on the PCB? The first filter bunch shows a lower voltage on top, b/c you have the lamp on it. The 200V readings are really the centers of 2-stack caps and would logically be about half of the top-cap voltage. 220V is half of 438V for all practical purpose.

Title: Re: Fender Hot Rod Deville - Recap - not sure of voltage readings
Post by: spunko on February 18, 2022, 10:25:31 am
Thank you very much for the explanation and the schematic.
I didn't realize they were 2-stack even with the schematic (tunnel vision). After reading your post I took a look at it and there it was  :BangHead:
I removed the bulb limiter and all voltages are ok versus the schematic. :icon_biggrin: