Home SET Asylum

Single Ended Triodes (SETs), the ultimate tube lovers dream.

[ Follow Ups ] Thread: [ Display  All  Email ] [ SET Asylum ]
[ Alert Moderator ] [ Edit ] [ Delete ]

A suspicious voltage!

First mucho thanks to Quest and J. Epsten.
Ok I made some fixes 1. I went ahead and put some volume pots in. No
reason to go "fooling" around with the thing until I get it working
int he first place! Ok and 2 I took out one of the cathode biasing
resistors on each of the fil. supply CT (that makes me wonder, if
before paralled 10 watt resistors were needed, when using only one do
I need a 20 watt??) Ok so I checked my B+ (between the plate screen
grid sockets in the empty 45 tube sockets) I got 321 VDC, close
enough to the 325 VDC i guess. OK BUT I did the same for the imput
tube, with the pots all the way "down" I got like 399 VDC and 421 VDC
with them all the way "up"!!! SO that is a bit more than the 180 VDC
the schematic calls for! Ok so I guess that the 100K ohm resistor on
the plates of the 5691 input tubes is a voltage dropping resistor?
BUT it doesn't seem to be doing any voltage dropping. OK check this
out. At the input of the choke I get about 470 volts, and at the
OUTPUT of the choke I get ABOUT 470 VOLTS! Is that right??? OK so one
last thing, the choke is the right size and rating and all, it is a
Hammond 158M, and I have the white lead on the "output" side and the
black one on the "input" (ie the black one is connected to the
rectifier) IS THAT backwards? I guess I should add that I am not
using a 5V4 because the filament windings on my power tansformer were
rated at a higher current than 2 amps ( I think it is 4A) so I have a
5AW4, a 5V3 and a 5U4, they all seem the same when it comes to the
output voltages of the power supply.
Where do I go from here?



This post is made possible by the generous support of people like you and our sponsors:
  Sonic Craft  

Follow Ups Full Thread
Follow Ups
You can not post to an archived thread.

[ Top Top of Page ] [ Contact Us ] [ Support/Wish List ] [ Copyright © 2025, Audio Asylum, all rights reserved ]
[ General ] [ Speakers ] [ Tubes ] [ Vinyl ] [ Digital ] [ Hi-Rez ] [ Video Asylum ] [ Cables ] [ Tweaks/DIY ] [ Music ] [ Films ]