Bottlehead Forum

Bottlehead Kits => S.E.X. Kit => Topic started by: bubba_pa on September 15, 2018, 01:48:39 PM

Title: New build won't pass voltage checks.
Post by: bubba_pa on September 15, 2018, 01:48:39 PM

Completed build.  Line voltage in 122 V.  Passed glow test.  All resistance checks within specs.  A side voltages good.  H2, H5, H4, and H7 all good.  B side not.  Got first set and rechecked connections.  Fixed B8 (poor connection).  Readings as follows:
   
    Before fixing B8       After fix B8
       16     63 V                  77
     *17     <1 V                 38
     *18     <1 V                 33
       19       0 V                   0
       20    312 V               354
       21    325 V               371
       24    240 V               325

Careful inspection I don't see and bulging caps.  Solder joints look good.  Had also attached the 8.2 ohm, 1W to 21U and 22U, not lower. Checked before reinstall and still in specs.  Moved to correct location, no change.

The B side 680 ohm, 3W does look like it might have gotten hotter than the A side companion.  Haven't pulled it out to check yet.

I have limited internet access and can't seem to get photos to load

Title: Re: New build won't pass voltage checks.
Post by: bubba_pa on September 15, 2018, 01:59:46 PM

Trying photos again

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fi67.tinypic.com%2F29zzn6o.jpg&hash=7bb49af04a9418fbe7a579f7371990ba94c7f80b)

Title: Re: New build won't pass voltage checks.
Post by: Paul Birkeland on September 15, 2018, 04:23:27 PM

18 and 19 connect together with a 249K resistor.  I see that it's there, is it well soldered in?  17 and 18 do not connect together but seem to have the same voltage.  Are you sure this isn't something like 33mV instead of 33V?

It can also be a good check to swap tubes between sides. 

Do you have additional photos/angles of the build? 

Title: Re: New build won't pass voltage checks.
Post by: bubba_pa on September 16, 2018, 11:48:41 AM

Thank you for response. I will check 18 & 19 and the resistance.  I had seen some confusion of mV with V before so don’t think that was it, but will recheck as I am very new at this.  Will also swap tubes and recheck.

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fi65.tinypic.com%2Fskvvjb.jpg&hash=e3a86fc8a399e3c3b3cc46e756dc3ee640aa9941)

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fi64.tinypic.com%2F2q9xu1j.jpg&hash=45528c85e91b79d32e55b52b27674e38e39bd19c)

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fi66.tinypic.com%2F20h83df.jpg&hash=da255f1590e57a9104d0bf32f5cbe46be2c2cb84)

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fi63.tinypic.com%2F311on86.jpg&hash=a74962a5b8647d87de5bd6167f279b1acd08371b)

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fi66.tinypic.com%2Fnyh8vn.jpg&hash=564aa44a205586c42d6a68a41380deb2bc5fb08a)

Other pics.  If something specific needed, let me know, can try to get.  Thanks again.

Title: Re: New build won't pass voltage checks.
Post by: Paul Birkeland on September 16, 2018, 12:14:54 PM

If this resistor is out of position, that would explain at least one of the spots where you have 30V.

Title: Re: New build won't pass voltage checks.
Post by: bubba_pa on September 16, 2018, 12:27:50 PM

will also check, but pretty sure 19L to 25L. 

Title: Re: New build won't pass voltage checks.
Post by: bubba_pa on September 16, 2018, 02:42:41 PM

Good troubleshooting from afar.  Swapping the tubes around gave me the answer.  Problems switched sides as well.  At least I know that the soldering isn't the problem.  My faith is restored.

What is the easiest way to obtain a replacement tube?  Through you, or open market? 

Is there any problem with pulling the bad tube and running it as a mono amp?  I'm kind of anxious to at least hear something.

Thank you again for helping to solve the problem.  I am off line until tomorrow, and will check then.

Title: Re: New build won't pass voltage checks.
Post by: Paul Birkeland on September 17, 2018, 04:29:24 AM

You can e-mail replacementparts(at)bottlehead(dot)com about this issue.  Be sure to provide your name, order number (if possible), and a link to this post.

-PB

Title: Re: New build won't pass voltage checks.
Post by: bubba_pa on September 17, 2018, 05:14:22 AM

Thank you.  Much appreciated.