First Time Crack Builder Need Assistance [solved]

prtuc2 · 12295

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Offline prtuc2

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Reply #45 on: April 29, 2014, 08:35:54 AM
Any inputs?



Offline Paul Birkeland

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Reply #46 on: April 29, 2014, 08:56:48 AM
I would suspect that there was a short circuit present here.

In all likelihood, replacing the four transistors on that board would likely be helpful.

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline prtuc2

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Reply #47 on: April 29, 2014, 09:11:52 AM
Is it possible to get it from bottlehead?  I don't want to order the wrong parts and more troubles.

And I already re-solder the back PCB board as you see in the previous post with the two PCB board pictures.



Offline Paul Birkeland

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Reply #48 on: April 29, 2014, 11:18:06 AM
Sure, you can contact replacementparts(At)Bottlehead(doht)com

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline prtuc2

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Reply #49 on: April 29, 2014, 12:00:24 PM
I just contact bottlehead for parts replacement for 2 of the 2N2222A transistors and the 2 TIP-50 transistors on the large PCB if that is correct? 



Offline Paul Birkeland

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Reply #50 on: April 29, 2014, 12:02:46 PM
That should do the trick.

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline prtuc2

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Reply #51 on: May 25, 2014, 04:47:48 AM
Is this what a blown fuse looks like?
(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fi828.photobucket.com%2Falbums%2Fzz208%2Fprtuc2%2FIMG_8711_zps50390e96.jpg&hash=3d83641ec16a5ef490bcba424d6718d4a6888554)

The amp won't power on at all, the picture doesn't show very clear.  There is a streak of dot silver line along the side of the fuse.



Offline Paul Birkeland

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Reply #52 on: May 25, 2014, 07:06:47 AM
You can measure the resistance of the fuse with your meter.  A blow fuse will be over the limit that your meter can measure, a good fuse will present a low resistance.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline prtuc2

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Reply #53 on: May 25, 2014, 07:36:56 AM
All my resistance values are way above normal.  Only a few terminals are within limit.

Terminal 1     above 3000k ohms
Terminal 2     800k ohms
Terminal 3     0
Terminal 4     5000k ohms
.... etc..

Except Terminal 6 and Terminal 10, most of the values are way above the values of the instruction manual.



Offline Paul Birkeland

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Reply #54 on: May 25, 2014, 08:22:03 AM
Can you provide an example of a resistance that's problematic?  Your report of terminals 1-4 look spot on. 

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline prtuc2

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Reply #55 on: May 25, 2014, 01:34:12 PM
Terminal 1         3500k ohms
Terminal 2         1000k ohms
Terminal 3         0
Terminal 4         1000k ohms
Terminal 5         3500k ohms
Terminal 6         2.494k ohms
Terminal 7         0         <<<< suppose to be 2.9k ohms?
Terminal 8         0
Terminal 9         OL       <<<< suppose to be 2.9k ohms?
Terminal 10       2.494k ohms
Terminal 12       0
Terminal 13       1000k ohms
Terminal 14       0
Terminal 20       0
Terminal 22       0

B3                     0       << suppose to be 2.9k ohms on the crack not sure on the sb upgrade is the same values
B6                     OL     << suppose to be 2.9k ohms

RCA ground lug: 0
Center pin:         100 ohms



Offline Paul Birkeland

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Reply #56 on: May 25, 2014, 02:53:21 PM
Does this Crack have a Speedball installed?

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline prtuc2

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Reply #57 on: May 26, 2014, 08:17:52 AM
Yes, this is with the speedball upgrade install resistance values.  As I double check the soldering joint, so far no luck.  I will continue to check on the joint connection.



Offline Paul Birkeland

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Reply #58 on: May 26, 2014, 08:21:44 AM
If the Crack was working pre-Speedball, then there are no resistance checks to do after installing the Speedball (as indicated by the manual).

If you started with a dysfunctional Crack and installed a Speedball, you will need to remove the Speedball and remedy the original build first.

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline prtuc2

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Reply #59 on: May 26, 2014, 08:47:02 AM
Crack w/o the speedball upgrade works fine for 1 day, then I upgrade the speedball.  The speedball upgrade works fine initially, but after 3rd days on terminal 14U the soldering iron starts melting and the right channel is completely out and after some recommendations you told me to get replacement parts for the 4 transistors for the larger PCB board for the speedball upgrade.  Now I can't seems to power up the amp.
« Last Edit: May 26, 2014, 08:53:48 AM by prtuc2 »