Page 55 voltage check wrong need help again.

Kurthaudio · 3520

0 Members and 1 Guest are viewing this topic.

Offline Kurthaudio

  • Jr. Member
  • **
    • Posts: 48
on: December 03, 2021, 06:34:04 AM
Hello again,

Short version:
#14 to 30: 9.6vdc

14 to 16: 87vdc

14 to 11: 175vdc



14 to 25: 0.9vdc

14 to 6: 45vdc

14 to 1: 175vdc

Some of the parts look different then stock. That’s because they have been soldered and desoldered to many times so I replaced them with equal values of what I have laying around.

I switched the tubes and the voltages stay exactly the same. I switched out the 100k pot again exact same voltages. If I disconnect the b+ voltage wires I get 260vdc as soon as I connect them it drops to 175?

This kit is kicking my but and once again I’m at a loss………



Offline Kurthaudio

  • Jr. Member
  • **
    • Posts: 48
Reply #1 on: December 03, 2021, 06:38:01 AM
Here is a pic



Offline Paul Birkeland

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 19354
Reply #2 on: December 03, 2021, 06:39:19 AM
You need more heat on those solder joints, most of them look pretty cold.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Kurthaudio

  • Jr. Member
  • **
    • Posts: 48
Reply #3 on: December 03, 2021, 06:44:29 AM
I can assure you they are not cold joints it’s Mundorf supreme diver gold solder and that’s just how it looks.

I do have several hounds that are not soldered until I get this voltage issue sorted



Offline Kurthaudio

  • Jr. Member
  • **
    • Posts: 48
Reply #4 on: December 03, 2021, 07:06:42 AM
Any other help?



Offline Thermioniclife

  • Sr. Member
  • ****
    • Posts: 756
Reply #5 on: December 03, 2021, 07:51:10 AM
I'm certain that 12 and 14 are cold. Balance control and the adjacent terminal strip look to have no solder, just solder them and don't worry about getting the voltage problem solved. How do you know that the unsoldered joints are not causing the problem?

Lee R.


Offline Kurthaudio

  • Jr. Member
  • **
    • Posts: 48
Reply #6 on: December 03, 2021, 08:08:11 AM
I know because I had this problem while everything was soldered. 14 and 11 are not soldered thats why they look like they are cold joints.

When I changed the balance pot I ran new wires and did not solder them. I wanted to leave them until I found out why I’m having this issue. To keep this from getting confused I’ll solder everything up take new readings and report back.



Offline Thermioniclife

  • Sr. Member
  • ****
    • Posts: 756
Reply #7 on: December 03, 2021, 08:17:23 AM
Holy smokes, there is an awful lot of silver in this solder 9.5%

Lee R.


Offline Kurthaudio

  • Jr. Member
  • **
    • Posts: 48
Reply #8 on: December 03, 2021, 08:24:59 AM
Ok guys, I soldered everything up. I’m still getting the same voltages as posted in my first post.

B seems ok with 14 - 30: 9.6vdc and 14 to 16: 87vdc

A seems to be my problem. I’m getting 14- 25:.9vdc and 14- 6: 45vdc.

Is it normal to be getting 175vdc @ 11 and 14?



Offline Kurthaudio

  • Jr. Member
  • **
    • Posts: 48
Reply #9 on: December 03, 2021, 08:27:56 AM
Lol solders like it too  >:(



Offline Thermioniclife

  • Sr. Member
  • ****
    • Posts: 756
Reply #10 on: December 03, 2021, 08:43:28 AM
Not having a beepre 2 I can't be certain but it looks like 11 is getting the b+ to the plate and 14 is ground. S measuring between 11 and 14 could show 175vdc. What voltage do you get on the equivalent terminals on the other tube?
/

Lee R.


Offline Kurthaudio

  • Jr. Member
  • **
    • Posts: 48
Reply #11 on: December 03, 2021, 08:50:11 AM
Yes you are correct 11 is B+ and 14 is negative

The solder tabs are basically just a junction that routs wires down to 1 and 4 of the A socket. I’m getting 175vdc at both 11 to 14 and 4 to 1

Earlier in the build the instructions ask for voltage check of the B+ power supply before it’s connected to anything and I get 260vdc. (250 +/- 20%)

It seems odd to me that once connected it drops to 175vdc?.?. Shouldnt it remain 260vdc?



Offline Thermioniclife

  • Sr. Member
  • ****
    • Posts: 756
Reply #12 on: December 03, 2021, 08:55:34 AM
No i'ts not funny, that's the plate voltage at the operating point. If you pull the tubes out the b
+ will jump back to about 260vdc. You have a voltage drop of around 45vdc due to the cathode resistor. No worries, march on soldier.
« Last Edit: December 03, 2021, 09:00:00 AM by Thermioniclife »

Lee R.


Offline Kurthaudio

  • Jr. Member
  • **
    • Posts: 48
Reply #13 on: December 03, 2021, 09:02:20 AM
Ok. Thank you clearing that up.

But how in the world am I only getting 45 volts at 6? And only .9vdc at 25? I do have 175@ 1.



Offline Thermioniclife

  • Sr. Member
  • ****
    • Posts: 756
Reply #14 on: December 03, 2021, 09:13:09 AM
As I stated earlier, I do not have a Beepre 2 or the schematics. My advise is follow the instructions, solder when told to do so, and preform any resistance and voltage tests when directed to do so. And then if any problems turn up than that's when to ask questions.

Lee R.