Bottlehead Forum

Bottlehead Kits => Legacy Kit Products => Quickie => Topic started by: denti alligator on September 28, 2012, 02:58:49 PM

Title: voltage check problem with PJCCS
Post by: denti alligator on September 28, 2012, 02:58:49 PM: I'm getting 15V at A5 and 30V at B5. What's gone wrong??

Yep, right channel isn't working. Can't seem to find where I went wrong.
Title: Re: voltage check problem with PJCCS
Post by: denti alligator on September 28, 2012, 03:30:21 PM: Never mind! I had one of the rectifier diodes in wrong. But in trying to remove it I snapped it in two. >:(

So I just soldered the f&%#er back together ... turned it around, checked the voltages: everything fine. Turned it on, and yes, it works. Should I have a new diode sent from BH or is what I did kosher?
Title: Re: voltage check problem with PJCCS
Post by: Jim R. on September 29, 2012, 05:41:07 AM: Sam,

You soldered a broken diode back together and it worked? That's amazing -- bet you can't do that again :-). Yes, I'd definitely get a replacement. It would be interesting to know how long that repaired diode will last, but I'm guessing it won't be long.

-- Now let's see you do that with a microprocessor chip!

-- Jim
Title: Re: voltage check problem with PJCCS
Post by: denti alligator on September 29, 2012, 06:27:41 AM: Yeah, I was sure it wouldn't work. Not only did it snap in two, I lost part of the bottom half, so really it's only a half-diode with a blob of solder. :D

I was sure it wouldn't work. Nice to be surprised! We'll see how long it lasts. In the meantime, I've put in a request for replacement with Queen Eileen.
Title: Re: voltage check problem with PJCCS
Post by: Irie Roover on October 13, 2012, 06:02:43 AM: Question,,
I seem to have a similar problem, but my voltage readings are on the A6 15v. & B6 32v.
which rectifier did I mess up? Any suggestion would greatly be appriciated.
Thx
Title: Re: voltage check problem with PJCCS
Post by: Paul Joppa on October 13, 2012, 06:55:25 AM: Quote from: Irie Roover on October 13, 2012, 06:02:43 AM
...
which rectifier did I mess up?
The one on the B side :^)

You may have the D-cells reversed - see the sticky top of this forum
Title: Re: voltage check problem with PJCCS
Post by: Irie Roover on October 13, 2012, 07:15:23 AM: I reversed the d cell and got A6 to put out 22v and the B6 is still at 32v.
Where do you think I should look next?
Title: Re: voltage check problem with PJCCS
Post by: Irie Roover on October 13, 2012, 08:16:38 AM: Looking a little deeper, I measured my MJE 350 transistor [ B side ] and found the outside poles measure 33v and the centre pole measures 22v. What next do think? Connect the red wire to the outside pole?
Title: Re: voltage check problem with PJCCS
Post by: Paul Birkeland on October 13, 2012, 08:51:20 AM: Resolder the center leg of the MJE350 on the offending side.

The middle leg and the case are tied together, and that connection likes to dissipate a lot of heat during soldering and cause problems down the road.

-PB
Title: Re: voltage check problem with PJCCS
Post by: Irie Roover on October 13, 2012, 09:00:05 AM: Thank you very much, I will try it now!
Title: Re: voltage check problem with PJCCS
Post by: Irie Roover on October 13, 2012, 01:11:50 PM: Unfortunately the MJE 350 resistor (middle post)will not exceed 23 v after resolding.
I may need to order another resistor and replace it!
Title: Re: voltage check problem with PJCCS
Post by: Paul Joppa on October 13, 2012, 05:36:39 PM: Middle post is the output of the current source, connected to the plate of the tube. 22 volts is excellent; it should be about 2/3 of the battery voltage.
Title: Re: voltage check problem with PJCCS
Post by: Irie Roover on October 13, 2012, 06:16:58 PM: So, when I measure volts at B6 I am to high at 33 v. When I power it on the right side is way loader than the left. When I measure the MJE 350 on side it's output is still high at 33v.
Any suggestions to get both channels even?
Title: Re: voltage check problem with PJCCS
Post by: Paul Joppa on October 14, 2012, 02:57:16 PM: B6 should connect to the middle lead of the MJE350 transistor. Apparently it does not, since the transistor is at 22 volts and B6 is at 33 volts.