Bottlehead Forum
Bottlehead Kits => Crack => Topic started by: Spharticus on July 30, 2021, 06:00:15 PM
-
Hey everyone. I've read as many posts as I can handle but it's all running together.
Crack, purchased LY but just put together a couple months ago. Built base kit, worked, sounded great. After a few weeks of use I started the speedball upgrade. Small board voltages checked-
OA 70
IA 187
B-A/B 0
IB 187
OB ? I didn't write it down :(
After small board, I tested resistance, all passed, tested the unit with headphones for about an hour and it sounded great.
Went for the big board. Now the two LEDs on the B side do not light up, and the 6080 tube doesn't glow now. Small 12AU7 tube does light up as expected.
small board:
OA 68
IA 212
B-A/B 0
IB 212
OB 81
Big board
OA 0
OB 1.5
G 0
B+ 213
T7 - 1.5
T9 - 0
Prior to speedball, B3 showed 2.94k and B6 showed 2.95k resistance.
Now, B3 shows 7.5M and B6 shows .7
I cleaned and reflowed OA, OB, G, B+ (all on large board), T6, T7, T9, T10, B3, B6, and terminals 7 and 9 on the power supply. Both my 9-pin LEDs and the 4 small speedball board LEDs are all lit up.
Not able to post photos...
Help? Thanks in advance.
-
You need to focus on the 6080 not lighting up. If the 12AU7 lights up but the 6080 doesn't, it's most likely that you've plugged the 6080 into the socket improperly without the keyway aligned.
Electrically the twisted green wires make the tubes glow. They go to the 6080 first, then to the 12AU7, so it's improbable that there's a wiring issue.
-
Me: spends hours going over everything multiple times cause not going to be embarrassed by having the problem be something stupid
Paul: even though they gave you a notch so you couldn't screw it up, you still did
Me:
Yup that was it. I knew that continuity between the two sockets had to be there, I thought the wiring to/from the 6080 socket got compromised. In a way it was but from the tube not plugged in right.
Thanks again...