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Old 27th Jan 2021, 8:12 pm   #8
MotorBikeLes
Octode
 
Join Date: Dec 2012
Location: Kirk Michael, Isle of Man
Posts: 1,747
Default Re: Telequipment D67 Fault

Right, you had a single scan. Either you have the controls set incorrectly (you did set them all as for "first time operation did you) or there is a fault in the trigger circuit, which should permit regular single scans.
You do need to check BOTH X and Y plates, as one side could be dead putting the trace off screen.
However, it does look more like the bright up circuit.
So, after checking all plate voltages, let us move on.
* Disconnect the lead from the CRT circuit to tag 210/176 on the BU board.
* Disconnect the lead from the CRT board to 210/307 on the BU board.
Carefully remove the base from the CRT and safely insulate it away from "stuff".
Check with a decent voltmeter that there are no dangerous voltages on the BU board.
If all is safe, you can connect a scope from the common line on the BU board to scope every point of interest on it. Make sure you try adjusting all trigger settings, and connect from the cal out to the A channel input. Centralise the (missing) trace by comparing the wave forms as you adjust the Y shift.
Les.
EDIT, safely insulate the loose wires of course!

Last edited by MotorBikeLes; 27th Jan 2021 at 8:14 pm. Reason: Added edit as above.
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