Cursed SEX kit has no power to A channel

Loquah · 2037

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Offline Loquah

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on: May 12, 2014, 10:29:13 PM
The SEX kit I am trying to repair is officially cursed!

Having installed the new 240V transformer, there is no power to the A channel tube socket, other than the heater power. All voltage measurements on A terminals are 0V. Can anyone suggest a likely place to begin hunting because I'm running out of ideas.

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Offline mcandmar

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Reply #1 on: May 13, 2014, 01:11:25 AM
Anything on 6 or 10?    Personally i would start again with resistance checks, something should show up there..

M.McCandless


Offline Loquah

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Reply #2 on: May 13, 2014, 02:09:10 AM
Grrrr!!!  >:(

You're probably right. I'm getting fed up and impatient now. I stopped working on it after that last post a few hours ago so I'll start with a resistance run through tomorrow when I get inspired to try again...

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Online Paul Birkeland

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Reply #3 on: May 13, 2014, 04:30:49 AM
The high voltage supply for both sides leaves terminal 4.  Since you have a working channel, one would guess that there is an interruption between terminal 4 and the non-working side.  (There will be a red wire that goes to a 680 Ohm 3W resistor, then a 100uF/450V cap) 

Paul "PB" Birkeland

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Offline Paul Joppa

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Reply #4 on: May 13, 2014, 09:48:20 AM
Inspect, and test if you can, power supply components (resistors and capacitors). The voltage surge in the milliseconds before the fuse blew (with the 120v transformer) could have damaged some of them.

Paul Joppa


Offline Loquah

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Reply #5 on: May 13, 2014, 11:36:42 AM
Thanks all. I'll start tracing the power circuit from Terminal 4 with an eye on the components.

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