Bittlehead crack hum [resolved]

[Applemacman]

Hi after several months of non problematic use, this morning I switched on my bottlehead crack sound only came out of right channel. So took it to the bench to have a look could not see any issues and bearing in mind been working fine for several months. Switched it back on and now no sound out of either channels but a low hum that gets a bit louder if you turn the volume up. Any ideas?

 

[Paul Birkeland]

I would check your voltages.

 

[Applemacman]

Ok voltages
1.  71
2.  154.1
3.  0
4.  154.3
5.  74
6.  0
7.  96
8.  0
9.  97.9
10. 0

Speedball
OA.  95.2
OB.  95.4
G.    0
B+.  153.1

 

[Paul Birkeland]

This is most likely a loose solder joint, but the voltages don't point to anything specific.  It doesn't take more than 15-20 minutes to just reflow each joint, but generally you can skip the solder joints with the LEDs and the joints on the power switch.

 

[Applemacman]

Well dont I feel the stupid one, after all this ive discovered its the rca leads from the riaa to the bothlehead crack which ate the issue.