News: Trouble logging in? Log in from the login page.
September 30, 2020, 06:58:13 PM

Author Topic: BeePre Resistance Check-Some Are Off  (Read 279 times)

0 Members and 1 Guest are viewing this topic.

Offline Deke609

  • Hero Member
  • *****
  • Posts: 1201
Re: BeePre Resistance Check-Some Are Off
« Reply #15 on: August 28, 2020, 05:53:13 PM »
740F is a pretty healthy temp, so I'd say that's not the issue.  Maybe try some magnifying glasses? I can't solder anything smaller than 1/2" copper pipe without them.

cheers, Derek
Derek
______

Roon Intel NUC ->  Yggdrasil DAC -> BeePre (w/ BeeQuiet and EML 300B)  -> Kaiju (w/ DCFil and EML 300B) or Stereomour II (2A3 [EML Mesh] and 45 Conversion [EML 45B])  -> Audeze LCD4

Offline taffet

  • Jr. Member
  • **
  • Posts: 13
Re: BeePre Resistance Check-Some Are Off
« Reply #16 on: September 12, 2020, 10:38:45 AM »
Hi-

I have re-soldered most all joints and board connections and trimmed the leads on the boards where there was some stick up. On the "B" side, I now get all the LEDs lighting up and have good voltage readings (save a few low mV readings that should be 0) except that I am getting 72V at Terminals 17 and B2 (instead of 90-110V) and 5.2V at D3 (instead of 3.5 to 4.5V). I have re-checked all my wiring over and over and can't find any mis-wire. I have been trying to keep off the forum until I exhaust possibilities but I am stumped. Perhaps there is still a bad solder joint or a mis-wire I keep missing?

Thanks, Michael

Offline Paul Birkeland

  • Global Moderator
  • Hero Member
  • *****
  • Posts: 13595
Re: BeePre Resistance Check-Some Are Off
« Reply #17 on: September 12, 2020, 11:42:16 AM »
Can you double check that the R1 resistors are properly located on the C4S board up front on that side?  Also double check that if you swap tubes between sides that the voltage stays put.  If it moves, that would suggest that it could be tube related.  The 72V at 17/B2 should either come with a voltage on the 5 lug strips under it that's not correct, or swapped resistors on the boards.
Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man

Offline taffet

  • Jr. Member
  • **
  • Posts: 13
Re: BeePre Resistance Check-Some Are Off
« Reply #18 on: September 12, 2020, 12:53:10 PM »
Hi Paul-

I swapped tubes and everything stayed the same except for a rarified minute 17/B2 were reading 90V! Then they went back to 72V. I checked the R1 resistors and they are correct. I have re-soldered all the wires and posts that connect to the C4S board and the 5 lug strip, and I sill get 72V.  I almost have it, it appears. Terminals 11 through 15 on the first 5 lug strip all read correct voltages. On the other 5 lug strip I get 16 (5V), 17 (72V), 18 (OV), 19 (9.87), and 20 (6.2mV). Must be a bad joint somewhere.

Thanks, Michael
« Last Edit: September 12, 2020, 01:14:37 PM by taffet »