Crack Voltage Check [solved]

[murpha77]

Hi All

I have just completed the kit and have passed the resistance check but unfortunately fail the voltage check.

1: -0.93
2: -0.91
3: 0
4: -0.91
5: -0.93
6: 0
7: 0
8: 0
9: 0
10: 0
11: -1.2
12: 0
13: -0.92
14: 0
15: 239.2
20: 0
21: 239.2

A1: 0
A2: 0
A3:0.8
A4: 0
A5: 0
A6: -0.9
A7: 0
A8: 0.8
A9: 0

B1: -0.9
B2: 0.8
B3: 0
B4 -0.9
B5: 0
B6: 0
B7: 0
B8: 0

Both valves light up (the 12AU7 in two places) however the LEDs don't.

I have done the gross error checks of checking the orientation of the capacitors, tube sockets, LEDs and the leads on the multimeter (which is why the negative readings don't make sense).

Any help is greatly appreciated.

Cheers

 

[Paul Birkeland]

T15 and T13 are connected with a 270 Ohm 5W resistor.  Yours is most likely not well soldered.  I'm also not so sure about the solder joint on 12L. 

Is the upper ground lug on the volume pot soldered?  (If it is soldered, try holing the iron on it a little longer to get the solder to flow)

 

[murpha77]

That was a quick reply!

You're right with 12L and the upper ground lug - they weren't soldered at all. Feel a bit silly missing those, a fresh set of eyes is always good!

The 270k ohm resistor is between terminal 12U and 13U (bottom of page 30 of the instructions), not 13 and 15 as you stated. Which is correct?

 

[Paul Birkeland]

The 270k ohm resistor is between terminal 12U and 13U (bottom of page 30 of the instructions), not 13 and 15 as you stated. Which is correct?

T15 and T13 are connected with a 270 Ohm 5W resistor. 

We are referring to two different resistors.

-PB

 

[murpha77]

I've just soldered the joints and now know what resistor you were talking about... Doh, engage brain before typing

 

[murpha77]

Another Crack is alive. Thanks for the quick reply and help. Time to enjoy it and start the speedball kit.

Cheers