dc filament heater - high impedance const. voltage - Page 4 - 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 12th October 2012, 07:03 AM   #31
diyAudio Member
 
Join Date: Aug 2008
So, an LM317 configured as current regulator, a better choice than LM317 as voltage regulator, to avoid overcurrent at startup.
  Reply With Quote
Old 12th October 2012, 05:56 PM   #32
tomchr is offline tomchr  United States
diyAudio Member
 
tomchr's Avatar
 
Join Date: Feb 2009
Location: Greater Seattle Area
Quote:
Originally Posted by Bigun View Post
As soon as I get back in front of a PC (all Mac at home) I'll try those mods.
Dude! Ever heard of VMware, Parallels, or VirtualBox? The latter is freeware, the other two payware (I think I paid $40 or $50 for VMware). Works great.

Quote:
Originally Posted by Bigun View Post
Whilst we don't appear to need fast feedback perhaps it helps. In a way it's a lazy way to deal with any h.f. hash from the mains that gets through the transformer and any h.f. hash generated by the rectifiers.
I highly doubt you'll be able to make a feedback loop that's fast enough to compensate for mains hash and rectifier spikes. Filtering - or just not generating the noise in the first place - works better here. But at least ensure that your circuit doesn't have gain at HF.

Quote:
Originally Posted by Bigun View Post
I mean that the current through the filament, when no signal is present, doesn't change over time.
So low drift? That probably depends mostly on the tempco and drift of your reference as well as that of the op-amp input offset.

~Tom
__________________
Modulus-86: Composite amp achieving 0.00018 % THD. Damn Good 300B, Novar Spud, 21st Century Maida Reg., Filament Reg., etc.
Neurochrome : : Audio - http://www.neurochrome.com/audio - Engineering : : Done : : Right
  Reply With Quote
Old 12th October 2012, 06:09 PM   #33
diyAudio Member
 
yagoolar's Avatar
 
Join Date: Oct 2004
Location: Mazowieckie, Jozefoslaw
Send a message via ICQ to yagoolar Send a message via Skype™ to yagoolar
Quote:
Originally Posted by tomchr View Post
Dude! Ever heard of VMware, Parallels, or VirtualBox? The latter is freeware, the other two payware (I think I paid $40 or $50 for VMware). Works great.

~Tom
VMware player is free of $. You can install and run one image at a time.
VMware Virtualization Products for Virtual Servers, Virtual Desktops, and Data Center. However not for Mac, AFAIK
  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
const. voltage & const. current on output FET ? Bernhard Solid State 64 20th October 2012 01:19 AM
DC Heater Voltage Bengali Tubes / Valves 9 2nd February 2009 05:19 AM
Is 6V DC too low for heater filament? Sunsun22 Tubes / Valves 8 29th December 2008 08:45 AM
DC filament ground and high voltage ground mikeyho Tubes / Valves 0 15th September 2005 06:52 PM
Troubl-shooting heater voltage for filament andy2 Tubes / Valves 12 10th January 2005 05:41 PM


New To Site? Need Help?

All times are GMT. The time now is 09:45 AM.


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