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Old 12th Apr 2018, 12:10 am   #9
peakfour
Triode
 
Join Date: Apr 2018
Location: Buxton, Derbyshire, UK.
Posts: 21
Default Re: Telequipment/Tektronix D75 No trace on Power Up.

Not been ignoring anyone, just late back home.

I did briefly have a look at the wee beastie earlier. The, now disconnected, 105v lead to earth measures about 7k5 ohms, so far from a short circuit.
I thought I'd try connecting it back up to the HT board via an ammeter, just to see what the current draw was. Bit of a crack and a nice spark that would do the Ducati proud.

The 105v rail on the PSU immediately dropped to 10v and stayed there, regardless of whether the wire was patched through or not. However on removing the mains supply and re-powering the scope, the voltage was back up at 105v, so it looks like it self protects and latches low until the power is dis, then reconnected.

I'll have a further play with sparky things indoors tomorrow.

Bill
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