Crack Build Problem - High values during resistance check

[jtee2]

I've just finished my Crack build (great detailed instructions/manual, btw!) and am getting high resistance readings at Terminal 6 & 10 (15-16M instead of 2.4K).

There's also continuity between B7 and B8/transformer posts 4 & 5/A9 and A4+A5.  I'm haven't been able to see where I may have shorted these (or detect it with continuity testing).

Do these two issues seem related?  Any obvious newbie mistakes for me to check?  Any ideas would be greatly appreciated!

BTW - I did connect transformer terminal 4 to 14U instead of 22L (as mentioned in the manual), so my layout doesn't match the manual photos.

[Paul Birkeland]

I've just finished my Crack build (great detailed instructions/manual, btw!) and am getting high resistance readings at Terminal 6 & 10 (15-16M instead of 2.4K).

The 2.49K resistors at the headphone jack provide this path to ground.  You will notice that they both attach to the bottom rung of the headphone jack where the black wire comes across.  I'd touch these joints up and that issue should go away.

There's also continuity between B7 and B8/transformer posts 4 & 5/A9 and A4+A5.  I'm haven't been able to see where I may have shorted these (or detect it with continuity testing).

The power transformer windings are pieces of wire, so this is a good thing.  These values will also drop when you have tubes in the sockets.

[jtee2]

I've just finished my Crack build (great detailed instructions/manual, btw!) and am getting high resistance readings at Terminal 6 & 10 (15-16M instead of 2.4K).

The 2.49K resistors at the headphone jack provide this path to ground.  You will notice that they both attach to the bottom rung of the headphone jack where the black wire comes across.  I'd touch these joints up and that issue should go away.

Thanks, Paul!  I'm glad that the continuity isn't an issue - this is definitely a stretch project for me

I touched up those joints and am still getting high resistance readings (that increase over time).  Any other obvious places I should check?

I've attached pics of the headphone jack joints (post touch-up) and the point where I'm reading resistance (with the red oval around it).

[Paul Birkeland]

What's the resistance between the bottom outer lug on the headphone jack and terminal 3? 

How about the resistance between that lug and 20?

[jtee2]

Bottom outer headphone lug -> Terminal 3 = 19-18M (varied a bit and was slowly dropping while I measured it)

Bottom outer headphone lug -> Terminal 20 = 0 (moved between 0 and 0.2)

[Paul Birkeland]

The black wire leaving the headphone jack and heading to toward the nine pin socket goes to terminal three. That would likely not be properly soldered and/or connected.

[jtee2]

Re-soldering a number of the ground connections (including terminal 3) did the trick, thanks so much!

On to a careful voltage check (left hand in pocket and rubber boots).