Resistance numbers incorrect?

Dynakitbuilder · 1663

0 Members and 1 Guest are viewing this topic.

Offline Dynakitbuilder

  • Jr. Member
  • **
    • Posts: 49
on: August 18, 2020, 11:04:07 AM
Just saw the entry about  #45 - shows 0 ohms on manual, I get fluctuation. OK?  Other readings on the 43-48 terminal strip : #43- 0; 44-*; 45-*; 46 - 0; 47 - *; 48 - 0.  Manual shows #46 as OL.
Thanks for the help.



Offline Paul Birkeland

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 19406
Reply #1 on: August 18, 2020, 03:38:07 PM
We have had an issue getting the automated PDF distribution of the Reduction manual to take the latest version.  Here are the correct resistance and voltage numbers for those terminals that are not quite right in your manual.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Dynakitbuilder

  • Jr. Member
  • **
    • Posts: 49
Reply #2 on: August 19, 2020, 09:23:59 AM
Thanks for the correct readings.  My readings are:  #43 - O ;   44 - fluctuating ;   45 - fluctuating;   46 - 0 ;   47 - fluctuating;     48 - O

OK, well I assumed these were OK, and went on to the Voltage checks.  Tubes glowed and LEDs lit up, but NO voltage readings on any terminal.  Power switch test showed same ( OL ) reading in off or on .
The power switch tested OK on the first test, but somewhere along the way I must have fried it?  Fuse not blown.  Need to order new power switch is pretty obvious, but don't know how to prevent this again.



Deke609

  • Guest
Reply #3 on: August 19, 2020, 09:43:25 AM
Tubes glowed and LEDs lit up, but NO voltage readings on any terminal.

If the tubes glowed and the LEDs lit, you had voltages and current flow. Do you mean they glowed/lit at first but then went out? If not, double check that your meter was set to measure DC voltage, not AC.

cheers, Derek



Offline Doc B.

  • Administrator
  • Hero Member
  • *****
    • Posts: 9570
    • Bottlehead
Reply #4 on: August 19, 2020, 10:44:13 AM
If the tubes and LEDs glow, there is voltage. So you need to figure why you're not getting a reading rather than whether or not the amp is getting power. My initial thought is that the meter setting or connection might need some attention. Maybe a test lead is not making good contact?

Dan "Doc B." Schmalle
President For Life
Bottlehead Corp.


Offline Dynakitbuilder

  • Jr. Member
  • **
    • Posts: 49
Reply #5 on: August 19, 2020, 11:19:05 AM
OK.  Went back and rechecked power switch and changed wire and attached/soldered.  Checked meter on Dcv - OK.  All voltage readings magically changed to correct readings EXCEPT #s 44 and 45.
My readings : #44 = 77v ;  #45 = 77v.  Correct should be 0V.  Cleaned up excess solder on 44 and reheated both.  Readings stayed the same.  Tubes and LEDs are all glowing.



Deke609

  • Guest
Reply #6 on: August 19, 2020, 11:28:02 AM
Those are the same DC voltages another recent builder got at 44 and 45: http://forum.bottlehead.com/index.php?topic=12523.msg115151#msg115151

So there may be errors in the copy of the resistance and voltage targets that PB posted above.  But wait for PB to confirm.

cheers, Derek



Offline Paul Birkeland

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 19406
Reply #7 on: August 19, 2020, 11:46:42 AM
If everything else is correct, then your meter is showing some voltage on the DC setting because it can't filter out the AC voltage that's there.  I wouldn't worry about that if those are the only two that are off.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Dynakitbuilder

  • Jr. Member
  • **
    • Posts: 49
Reply #8 on: August 20, 2020, 01:27:59 AM

Thanks to Derek and PB for all the help and advice.  I will sally forth and try a set-up to my TT.
Please stay healthy and sane.



Offline Dynakitbuilder

  • Jr. Member
  • **
    • Posts: 49
Reply #9 on: August 20, 2020, 06:10:40 AM
Just hooked up the Resistance pre-amp to my system - fine music - listening to vintage late 50s jazz by Art Pepper and Chet Baker.  A few questions:  Necessary to add rubber feet?  Are tube shields used for heat dissipation and/or EMI ?  I love to look at those glowing tubes.  OK to experiment with the sound with and without shields? Do you expect a certain time for "burn-in" for the pre-amp ?
Looking forward to building the Integration to see even better performance.
Thanks again for the product and service!  Tom



Offline Paul Birkeland

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 19406
Reply #10 on: August 20, 2020, 07:29:56 AM
Yes, the rubber feet are mandatory for airflow.  The tube shields are for noise, not for heat. 

Burn in should be roughly 100 hours. 

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man