Fisher 800c selenium rectifier pictures - diyAudio
Go Back   Home > Forums > Amplifiers > Tubes / Valves

Tubes / Valves All about our sweet vacuum tubes :) Threads about Musical Instrument Amps of all kinds should be in the Instruments & Amps forum

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 10th April 2009, 07:23 AM   #1
diyAudio Member
 
Join Date: Apr 2009
Default Fisher 800c selenium rectifier pictures

I did a search and got why to change and how to change so
can someone post pictures of the 800c selenium rectifier so I can tell if mine is original I have a square bridge about 1 inch maybe a tad bigger square and maybe 3/8th inch thick mounted on the side.

Thanks
  Reply With Quote
Old 10th April 2009, 08:12 AM   #2
chrish is offline chrish  Australia
diyAudio Member
 
chrish's Avatar
 
Join Date: Oct 2003
Location: Sydney
Maybe post a picture of what you have got, then someone can tell you if it is the selenium rectifier.
  Reply With Quote
Old 10th April 2009, 10:35 AM   #3
diyAudio Member
 
Frank Berry's Avatar
 
Join Date: Sep 2003
Location: Midland, Michigan
If the Fisher is like the old HH Scott amplifiers, the selenium is a bridge rectifier. The size is about correct.
There should be four connections. Two directly from the power transformer, one (the - output) to the electrolytic (possibly through a resistor) and the another (the + output) should be tied to chassis ground.
Hope this helps.
__________________
Frank
  Reply With Quote
Old 10th April 2009, 12:12 PM   #4
diyAudio Member
 
Join Date: Apr 2003
Location: Portland,Oregon
Blog Entries: 4
Send a message via AIM to DigitalJunkie
Does it look like a stack of square metal plates,with a space between each plate,kinda "finned" looking? If so,it's selenium.

Selenium rects on google images
  Reply With Quote
Old 10th April 2009, 01:07 PM   #5
diyAudio Member
 
Frank Berry's Avatar
 
Join Date: Sep 2003
Location: Midland, Michigan
The selenium bridge in the old HH Scott amplifiers is a flat pack ...
no fins. It has two solder terminals on one side and two terminals on the opposite side. It's mounted to the chassis with a small mounting bracket. Fisher may have used a similar bridge.
__________________
Frank
  Reply With Quote
Old 10th April 2009, 04:32 PM   #6
diyAudio Member
 
Join Date: Apr 2009
Ok here's some pics
Attached Images
File Type: jpg 800c 002.jpg (22.7 KB, 156 views)
  Reply With Quote
Old 10th April 2009, 04:32 PM   #7
diyAudio Member
 
Join Date: Apr 2009
Mine looks like the bottom one in this picture
Heres the caption from the picture

Two old selenium rectifiers and on the foreground a modern silicium bridge rectifier
Attached Images
File Type: jpg selenium.jpg (58.3 KB, 138 views)
  Reply With Quote
Old 10th April 2009, 05:59 PM   #8
diyAudio Member
 
Join Date: Apr 2004
Location: Monroe Township, NJ
FWIW, I suggest that no prisoners be taken and 4X 100 PIV Schottky diodes be installed. Remember, the negative rail does double duty providing O/P tube bias and heater power. "Zero" switching noise in the bias supply can't hurt and may help. An adjustment to the rail voltage is probably necessary, given the very small forward drop in Schottkys.
__________________
Eli D.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Fisher 800c static,crackle skiman762 Tubes / Valves 2 9th April 2009 03:59 PM
Fisher 800c neg bias problem Glowin Plates Tubes / Valves 10 26th September 2008 08:39 AM
fisher 800c intermitant hum slhoward Tubes / Valves 1 28th May 2007 04:16 PM
fisher 800c modifications slhoward Tubes / Valves 1 15th May 2007 11:25 PM
Distortion in Fisher 800C Glowin Plates Tubes / Valves 1 2nd November 2005 06:57 PM


New To Site? Need Help?

All times are GMT. The time now is 06:07 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2