First Time Crack Builder Need Assistance [solved]

prtuc2 · 12296

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Offline Paul Birkeland

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Reply #60 on: May 26, 2014, 11:45:06 AM
Hmm, try running the amp without the 6080 to see if the voltages at terminals 1-5 look to be about correct.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline prtuc2

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Reply #61 on: May 26, 2014, 12:11:35 PM
Terminal 1-5 voltages shown as 0.  The 6080 tube is taken out and the 12AU7 tube isn't lighten up either.  I am sure there is power cause I got a shock accidentally touching the power supply.



Offline Paul Birkeland

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Reply #62 on: May 26, 2014, 02:12:44 PM
If the 12AU7 isn't glowing, then there is an issue with the twisted pair of wires going from power transformer terminals 4 and 5 to B7/B8 and A4,5/A9. 

We have been seeing some builders lately who accidentally cut one of the wires coming out of the transformer itself, so that's worth looking at as well.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man



Offline Paul Birkeland

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Reply #64 on: May 26, 2014, 05:21:29 PM
If the 6080 is in the socket, does it glow?

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline prtuc2

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Reply #65 on: May 26, 2014, 05:46:08 PM
Both tubes does not glow, seems the current is not going through the socket.  Matter of fact the led does not glow, before the problem occurred all the led lit up just fine.



Offline Paul Birkeland

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Reply #66 on: May 27, 2014, 04:59:24 AM
What is the AC voltage between power transformer terminals 4 and 5?  (Put one probe on each terminal)

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline prtuc2

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Reply #67 on: May 27, 2014, 09:01:00 AM
Both terminal AC voltage is 0.  Seems no power is going through the unit, could it be the power cord module overheat or damage?



Offline Paul Birkeland

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Reply #68 on: May 27, 2014, 09:13:11 AM
What about the AC voltage between power transformer terminals 1 and 2? 

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline prtuc2

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Reply #69 on: May 27, 2014, 09:38:22 AM
All the terminals include the B socket and A socket all the AC voltages are at 0.

Except B6 and terminal 9U both show 0.588V, B6 is connected to 9U and that is the only spot on the amp actually got any voltage reading, while the rest of the amp is at 0.



Offline Paul Birkeland

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Reply #70 on: May 27, 2014, 07:51:50 PM
Power transformer terminals 1 and 2 receive the incoming AC line voltage.  If you have 0V there, your amp isn't plugged in, your power switch is off (or melted), or your fuse is blown.

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline lordnikon

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Reply #71 on: May 28, 2014, 03:52:20 PM
Your picture below indicates you have the wrong orientation of the Speedball PCB board (with the large heat sinks) The printed words "TOP" should be facing south towards the 12AU7 socket and not the 6080 socket.

http://s828.photobucket.com/user/prtuc2/media/P1000273_zpsc6f95926.jpg.html




Offline prtuc2

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Reply #72 on: May 28, 2014, 04:31:52 PM
I have been suspecting the power switch probably melted when I desoldering the solder iron, just going to re-order an exact pair of fuse and power switch to see if that was the problem or not. 

Thanks for pointing out my large PCB is reversed, I will fix it this weekend.

Really appreciate all the help, so far.



Offline Paul Birkeland

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Reply #73 on: May 28, 2014, 06:58:14 PM
The board is functionally the same in either orientation, and will work provided you have the connections attached in the correct positions. 

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline lordnikon

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Reply #74 on: May 28, 2014, 07:26:26 PM
I came across the same problem as I reversed the orientation of the Speedball PCB. The LEDs didn't work. Once I rotated the board, it worked.  ???