Help needed to find these rare values! - Page 5 - diyAudio
Go Back   Home > Forums > Amplifiers > Tubes / Valves
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

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
Thread Tools Search this Thread
Old 28th September 2004, 03:21 AM   #41
diyAudio Member
jamesjung21's Avatar
Join Date: Dec 2003
Location: New Zealand
Any opinion for above?
  Reply With Quote
Old 28th September 2004, 05:15 AM   #42
diyAudio Senior Member
fdegrove's Avatar
Join Date: Aug 2002
Location: Belgium

Stop crying...Can't have that...

And hey, is it true that putting a 100nF from each heater terminal to ground help to reduce RF noise?

And do I really need to use wires of the gauge just enough to carry the required current for heater wire?
No more metal than strictly necessary.

Of course, I'll use solid wires & twist'em tight for the rectifier HT with AC, but I'm planning to regulate the voltage for the 4 singnal tubes...
Still. It won't hurt. Keep heater harness away from the signal path too.

Hopefully, it'll isolate some of the noise generated by the rectifier tubes...
What noise?

  Reply With Quote
Old 19th November 2004, 06:28 PM   #43
diyAudio Member
jamesjung21's Avatar
Join Date: Dec 2003
Location: New Zealand
Yeah! exams are finished !!

It was holding me for almost 3-4 months !!

And I finally got ONE better potted transformer (Paeco by HP I guess) and is much more powerful with proper primary windings (115+115= 230V).

But ther's no powerful-enough center-tapped sec. winding, but two powerful single windings.

So could you guys help me to design a hybrid rectification for this transformer?

I basically got 2 secondary windings found to be useful:

One is rated for 302V @ 0.2A, but the voltage seems to be too high for hybrid rectification to be used to obtain approx. 250VDC..

The other one is rated for 205V @ 0.25A (with a tap rated for 167V, but that's not a CT... let's ignore the odd tap and use the 205V one...) I'll use the 0V and 205V taps to use the winding as a single winding.

----- 0V
l---- 167V
----- 205V @ 0.25A

Here are the things that I have, to be used for the PS:

*12pcs 100ohm 50W Aluminium Clad Dale resistors. I can connect many of these to increase the resistance.

*Many EZ80 rectifiers.

*A pair of MKP 60uF 370VAC motor-run caps.

I don't have any more space on my chassis to add another large component, like a choke or a cap....

Please remeber that this SINGLE transformer will supply BOTH channels. I'll build TWO PSU, ONE for EACH cahnnel.

I'm finding it very difficult to design one by myself, because the PSU designer program is not available for hybrid rectification, and both tube and SS diodes/rectifiers are used in this... (tube rect. has higher forward V drop than the SS diodes.... Then how do I combine the two to obtain the same, single voltage? ).

Please help, please, please please !!!
  Reply With Quote
Old 23rd November 2004, 04:02 AM   #44
diyAudio Member
jamesjung21's Avatar
Join Date: Dec 2003
Location: New Zealand
Need help!! ......
  Reply With Quote


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
*rare*brand New Avalanche 18 Brand New *rare* thadman Swap Meet 2 17th September 2007 04:20 PM
Info needed on this very rare Kenwood deck Kuja Analogue Source 0 29th September 2006 02:19 PM
Help needed to find PVM 1702 Alexiss Digital Source 9 19th August 2006 08:03 PM
Help desperately needed with find TomJ Solid State 3 2nd May 2003 08:24 PM
Cant find capacitor values - help purist Multi-Way 4 29th April 2003 07:50 PM

New To Site? Need Help?

All times are GMT. The time now is 12:53 PM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2