Go Back   Home > Forums > > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Tubelab Discussion and support of Tubelab products, prototypes and experiments

Reply
 
Thread Tools Search this Thread
Old 2nd July 2020, 03:26 PM   #811
Tubelab_com is offline Tubelab_com  United States
diyAudio Member
 
Tubelab_com's Avatar
 
Join Date: Jul 2005
Location: West Virginia panhandle
Quote:
Would this cap work: ESMH160VSN104MA80T United Chemi-Con | Mouser
It should be fine.

Quote:
it might be my PT complaining about having too much current drawn from it.
I have built several amplifiers including my original Lexan TSE with a transformer that was too small with good luck except for the heat produced.

When a transformer is feeding a rectifier follower by a cap input filter most of the current is drawn right at the peak of the sine wave. The TSE and TSE-II are worse in this regard because two out of three secondaries have this type of load. This can cause the transformer to exhibit higher losses at the peak current point.

An oversized transformer is good in this case. I am using a Hammond 372HX on my TSE-II because I had one. It was originally intended to power TWO SPP boards at the same time, which it did just fine, but wouldn't work with my odd packaging scheme that I made for this amp.

The 372HX works good in the TSE-II with 300B's at about 385 volts, and 2A3's at about 380 volts (way over spec). The increased filament draw is the reason for the 5 volt B+ drop.

The 370FX should do fine with 45's.

Edit, My email box tells me that AES (tubesand more.com) has "everything 10% off this week." I don't know if that's a deal or not since I haven't bought anything from them in a few years.
__________________
Tubelab, I blow stuff up so that you don't have to.

Last edited by Tubelab_com; 2nd July 2020 at 03:29 PM.
  Reply With Quote
Old 7th July 2020, 08:10 PM   #812
winggo is offline winggo  United States
diyAudio Member
 
Join Date: Dec 2004
Location: Sioux Falls, SD
Default Still no volts at C11

It's me again. I had no voltage at C11. I started tracing voltages from the IC's (both channels) toward the c11 and c9. Right off I found that IC1 had 419 v at A but nothing at S & G. IC2 had 419 v at A and 211 +/- at S & G. I took an old IC from my TSE I board and tried it but got same result, but I know it is easy to short out these ICs so that one may be bad also.

I'll order a couple of new ICs (one extra) and see if that solves the no voltage problem.
  Reply With Quote
Old 8th July 2020, 12:22 AM   #813
Tubelab_com is offline Tubelab_com  United States
diyAudio Member
 
Tubelab_com's Avatar
 
Join Date: Jul 2005
Location: West Virginia panhandle
OK, you have the right voltage going into IC1, but nothing coming out. The voltages are even low without the 5842 tube (post#787). There are three likely reasons for this. A bad chip, R27 or R28.

I looked at the picture that you attached in post #790 and it looks like R27 may be the wrong part. It should be 330 ohms, orange-orange-black-black-brown. Yours looks like orange-orange-black-orange-brown, which would be 330K. This would result in very low voltage coming out of the chip.

I can't tell if the colors are correct on R16 in the picture, but it should also be 330 ohms.
__________________
Tubelab, I blow stuff up so that you don't have to.
  Reply With Quote
Old 8th July 2020, 05:09 PM   #814
debije is offline debije  Netherlands
diyAudio Member
 
Join Date: Feb 2004
Location: Sittard, The Netherlands
I recently got a good deal on a pair of Gold Lion PX300B tubes and 2 sets of 5842 tubes. So I would be interested in building a TSE. I allready built the SSE 2.5 years ago, and it is still working great.

I would like to use a pair of DHT regulators I have, each running of a separate transformer tap and also a regulator for the 6.3V 5842 heaters. Would it be possible to connect this to the pcb and not use the on board heater supply?

The power transformer I have has one 5V 3A tap, 2x 6.3V 2A taps and one 6.3V 4A tap for the heaters, all with center tap, so that is nice. The HT tap is 380-0-380V, so that is a bit high. Will have to bring that down a bit, maybe with something like a Maida regulator of different rectifier tube? I am not sure if the Gold Lion tubes also have this thermal runaway problem, the data sheet says it is good up to 450V. I will be using 5K opt's.

I am hoping someone can say if this will work with the parts I have. If someone has an old TSE board they are not using, that would probably also be good enough for what I would like to do.

Thanks,

Rob.
  Reply With Quote
Old 8th July 2020, 06:11 PM   #815
winggo is offline winggo  United States
diyAudio Member
 
Join Date: Dec 2004
Location: Sioux Falls, SD
You were right George. That R27 was 330K I replaced it with 330 and I am now getting the correct voltage at C11. My eyes are so bad I can't make out those color bands very well. Now on the the next step. Thanks
  Reply With Quote
Old 8th July 2020, 09:42 PM   #816
winggo is offline winggo  United States
diyAudio Member
 
Join Date: Dec 2004
Location: Sioux Falls, SD
I have my 300b tubes in and I get 400 B+ volts. What should my two volt meters be set to (Volts or amps) and what should the desired current be?
  Reply With Quote
Old 8th July 2020, 09:52 PM   #817
itsikhefez is offline itsikhefez  United States
diyAudio Member
 
Join Date: Aug 2015
After a 14 year run, the TSE must DIE!
I have my TSE 300B at ~400V B+ and 70-90mA (there are tradeoffs for each setting)

To adjust it, you need your DMM set to measure Volts.
Since you are measuring on a 10R resistor, if your DMM reads 700mV, then your bias is set at 70mA.
Also make sure your output transformers are rated for the bias you are setting..
  Reply With Quote
Old 8th July 2020, 10:36 PM   #818
brl0301 is offline brl0301
diyAudio Member
 
Join Date: Dec 2019
Quote:
Originally Posted by winggo View Post
I have my 300b tubes in and I get 400 B+ volts. What should my two volt meters be set to (Volts or amps) and what should the desired current be?
I run my amp at 380v and 65ma. Your b+ should drop a bit as you increase the bias
  Reply With Quote
Old 9th July 2020, 07:16 PM   #819
Tubelab_com is offline Tubelab_com  United States
diyAudio Member
 
Tubelab_com's Avatar
 
Join Date: Jul 2005
Location: West Virginia panhandle
Quote:
I would like to use a pair of DHT regulators I have, each running of a separate transformer tap and also a regulator for the 6.3V 5842 heaters. Would it be possible to connect this to the pcb and not use the on board heater supply?
All of this is possible, but it's a matter of how much work is involved. Assuming a TSE-II board:

Quote:
I would like to use a pair of DHT regulators I have, each running of a separate transformer tap
The filament of the two output tubes are in parallel, done with two heavy traces between each of them. The trace for the positive connection is doubled up on the top and bottom side of the board to support the high current drawn by 2A3's without voltage drop. This trace would need to be cut in three places, but it would not be too hard to do.

The ground trace running to the tubes is an even bigger trace, also doubled up on top and bottom sides. It also connects to other components, so cutting it would not be a wise choice.

This would leave the negative side of both filaments connected directly to ground. I prefer this connection, but it means that tube current measurements must be made in the plate circuit. One would connect your external filament regulator's negative leads to ground, preferably directly at the tube socket pins on the board. The positive connections from each regulator would go directly to the positive filament pins on the tube socket on the bottom of the PC board. The filament regulator components would not be populated on the board.

Quote:
also a regulator for the 6.3V 5842 heaters.
No board modifications are needed here. Leave out D1, D4, D5 C1, C2, C12, C13 and R3 at build time. Connect the negative side of your external 6.3 volt source to the board where D4 and D5 meet, and the positive side to board at the end of R3 closest to V1 (one of the 5842's).

You could probably drop enough B+ voltage by using a 5U4 tube and reducing the value of C4. Using a choke with a lot of DCR will help too.

An external power regulator could be used for the B+ voltage if needed. It can be connected to the board in place of or in series with the choke. The on board negative supply would still be used.

The same steps would be needed if you were using the original TSE board. It might be a little bit easier to make the PC board cuts on the old board. Both positive and ground filament connections could be easily cut as they are not doubled up so that the current measuring resistors or meters could be placed in the filament side (not B+). The old TSE board is considerably smaller and heat build up could be an issue with 300B tubes with B+ levels around of over 400 volts.

If I was to do this myself I would use a TSE-II board because it is bigger and has better thermal management, but I still have 3 of the old boards left if you choose to go this route.
__________________
Tubelab, I blow stuff up so that you don't have to.
  Reply With Quote
Old 10th July 2020, 08:41 PM   #820
debije is offline debije  Netherlands
diyAudio Member
 
Join Date: Feb 2004
Location: Sittard, The Netherlands
Hi George,

Thanks for the detailed desciption of how to use the seperate regulators. The reason I wanted to use them is because I thought this would be best for DHT tubes. Since you built the pcb with one regulator for both 300B tubes, this would suggest that it isn't really needed to have them seperate. I am not really sure what to do, seems a waste to cut up a nice new pcb if the benefit is not going to be a lot. I do have very efficient speakers, 102 dB/1W/1m, so if there is any hum from the amp, I will definately hear it.

Would you suggest building the TSE first the way it is supposed to be built, and maybe replace the regulators later if there is a reason for it? I could allways use the regulators for another project.

Thanks,

Rob.
  Reply With Quote

Reply


After a 14 year run, the TSE must DIE!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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
DIY'er of the Year! CanAm Man Pass Labs 2 2nd January 2015 10:26 PM
Happy New Year..."Happy New Year" to all . Best Wishes and God Bless Albert Walfie Fixer The Lounge 12 1st January 2012 11:02 AM
Baaa...New Year same as the Old Year T in AZ The Lounge 36 7th January 2010 09:06 PM
xp20 year oct 08/xp20 year 2009 GUSTAV1966 Pass Labs 2 12th December 2009 04:26 PM
Best New Year Yonnat Pass Labs 0 1st January 2004 11:02 AM


New To Site? Need Help?

All times are GMT. The time now is 12:15 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
Copyright ©1999-2020 diyAudio
Wiki