Vacuum Tube OTL power amp!! - Page 29 - 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 25th October 2011, 10:43 PM   #281
M Gregg is offline M Gregg  United Kingdom
diyAudio Member
 
M Gregg's Avatar
 
Join Date: Jun 2010
Location: UK
Quote:
Originally Posted by flatheadmurre View Post
Trying to straighten out my PSU design.

6800uF in each +-150 rail one dropping resistor.

With my 115v transformer not here i have to guess but seems like a little to less for real quite one ?

M Gregg did you go regulated for small signal HT ?
Do what you know works best for you,
You could use electronic choke.....

I Thought about using a Maida,
however I just used 47uF- 10H choke-47uF.
470K across the last cap. 50mA fuse.
Regulated DC heaters for first two 6SN7's.

The type of rectifier will make a difference...BYV96E or hex or standard + snub.

Regards
M. Gregg
__________________
What is the sound of one hand clapping?

Last edited by M Gregg; 25th October 2011 at 10:47 PM.
  Reply With Quote
Old 25th October 2011, 11:16 PM   #282
diyAudio Member
 
Join Date: Mar 2011
Location: Jarna
For rectifier itīs one fits all.

Meaning that i bought a reel of Philips BY 448 at sale and they will do.
  Reply With Quote
Old 26th October 2011, 10:59 AM   #283
M Gregg is offline M Gregg  United Kingdom
diyAudio Member
 
M Gregg's Avatar
 
Join Date: Jun 2010
Location: UK
Quote:
Originally Posted by flatheadmurre View Post
For rectifier itīs one fits all.

Meaning that i bought a reel of Philips BY 448 at sale and they will do.
Standard Avalanche,
Good spec 2A 1500V
The 6C33C stage required current not voltage so I used higher current diodes in this section..also inrush for the high capacitor values on each rail.
I used a 1K 12W on the common rail. 4700uF across each rail and 1000uF across the +/- rails and 4.7uF film cap.

Any snubbing?

Regards
M. Gregg
__________________
What is the sound of one hand clapping?

Last edited by M Gregg; 26th October 2011 at 11:11 AM.
  Reply With Quote
Old 26th October 2011, 11:28 AM   #284
diyAudio Member
 
Alastair E's Avatar
 
Join Date: Feb 2004
Location: South Wales
Hmmm....

Not sure a small 2A diode will put up with the 'inrush current' if used in the two O/P stage rail supplies....

May need bigger diodes, or guess you could paralell em up....
__________________
Das Beste Oder Nichts
  Reply With Quote
Old 26th October 2011, 01:04 PM   #285
M Gregg is offline M Gregg  United Kingdom
diyAudio Member
 
M Gregg's Avatar
 
Join Date: Jun 2010
Location: UK
The Alpairs are getting another bashing, 3hrs so far again

Poco Legend...

You got to think current with this.....cables, fuses, diodes,
sun tan...LOL

Snow machine for cooling...oven gloves for the volume control....LOL

Its working great......

Regards
M. Gregg
__________________
What is the sound of one hand clapping?
  Reply With Quote
Old 26th October 2011, 04:13 PM   #286
diyAudio Member
 
Join Date: Mar 2011
Location: Jarna
The toroids has arrived.

The smallest one in the picture is supposed to be a 500VA 2x115.

Click the image to open in full size.

BUT itīs now a 50VA 2x15

Talked to airlink they apologized and makes me a new one in a week !!!!!

This is now officially the Murphys law OTL amp.
  Reply With Quote
Old 26th October 2011, 04:17 PM   #287
diyAudio Member
 
Join Date: Mar 2011
Location: Jarna
Youīre probably right about the diodes.

Have some from a UPS they will be more up to the job.

Still angry about the transformers.
  Reply With Quote
Old 26th October 2011, 04:21 PM   #288
M Gregg is offline M Gregg  United Kingdom
diyAudio Member
 
M Gregg's Avatar
 
Join Date: Jun 2010
Location: UK
Quote:
Originally Posted by flatheadmurre View Post
The toroids has arrived.

The smallest one in the picture is supposed to be a 500VA 2x115.

Click the image to open in full size.

BUT itīs now a 50VA 2x15

Talked to airlink they apologized and makes me a new one in a week !!!!!

This is now officially the Murphys law OTL amp.
50VA 2x15?

Thats a shame....What Transformer specs are you using?
Do you know the physical size of the 500VA 2x115.
Can you build arround it. (leave a space).
Are all the others OK?


Regards
M. Gregg
__________________
What is the sound of one hand clapping?
  Reply With Quote
Old 26th October 2011, 04:36 PM   #289
diyAudio Member
 
Join Date: Mar 2011
Location: Jarna
I got the measurements for the toroid but thereīs a little lack of trust right now.

Itīs very crowded inside so iīll finish the small signal HT and then itīs back to waiting.
  Reply With Quote
Old 26th October 2011, 04:43 PM   #290
M Gregg is offline M Gregg  United Kingdom
diyAudio Member
 
M Gregg's Avatar
 
Join Date: Jun 2010
Location: UK
Quote:
Originally Posted by flatheadmurre View Post
I got the measurements for the toroid but thereīs a little lack of trust right now.

Itīs very crowded inside so iīll finish the small signal HT and then itīs back to waiting.
I used

TT0913.<<Airlink.

I had no problems with them. YMMV.

Do you not trust them?

Regards
M. Gregg
__________________
What is the sound of one hand clapping?
  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
FS: Vacuum Tube Monoblock Power Amp Kit cuibono Swap Meet 13 7th May 2011 01:49 AM
Vacuum tube VCO Bitrex Tubes / Valves 1 15th March 2011 01:07 PM
HLLY MK III 3 Vacuum Tube Headphone Amplifier Pre Amp hllyelec Vendor's Bazaar 2 19th July 2009 06:54 AM
S3E Vacuum Tube angsuman Tubes / Valves 12 15th March 2008 06:12 AM
DIY Vacuum tube amp turbo_h4 Tubes / Valves 2 1st July 2004 02:48 AM


New To Site? Need Help?

All times are GMT. The time now is 05:48 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright Đ1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2