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Uncle Bulgaria · 1st Nov 2019, 7:06 pm

That's very clear, Tony. Thank you. I hadn't considered that application of C701, which was why I couldn't see how T704/5 wouldn't just stay on. I suppose that once C701 is charged, the DC is blocked so there is no current?

(I should add that I've been pestering Tony with PMs because of his previous experience with the CR 210, but thought I should share the load rather than prevail overmuch on his generosity!)

Situation:

On; stopped; K5 engaged; motor running (as if a cassette is in).

T704: Vb=690mV
T705: Vb=8mV
T706: Vc=273mV

T705 is a new BC548C. C701 is a new electrolytic. T706 is a new BC558B.

Play engaged, then stopped. Pinch roller still engaged, 'play' LED off.

T704: Vb=640mV
T705: Vb=9mV
T706: Vc=1.2mV (with joystick in 'stop'. Returning it to 'neutral' gives 9mV).

1st Nov 2019, 7:06 pm	#3
Uncle Bulgaria Nonode Join Date: May 2016 Location: Cornwall, UK. Posts: 2,338	Re: Uher CR 240 solenoid does not disengage. That's very clear, Tony. Thank you. I hadn't considered that application of C701, which was why I couldn't see how T704/5 wouldn't just stay on. I suppose that once C701 is charged, the DC is blocked so there is no current? (I should add that I've been pestering Tony with PMs because of his previous experience with the CR 210, but thought I should share the load rather than prevail overmuch on his generosity!) Situation: On; stopped; K5 engaged; motor running (as if a cassette is in). T704: Vb=690mV T705: Vb=8mV T706: Vc=273mV T705 is a new BC548C. C701 is a new electrolytic. T706 is a new BC558B. Play engaged, then stopped. Pinch roller still engaged, 'play' LED off. T704: Vb=640mV T705: Vb=9mV T706: Vc=1.2mV (with joystick in 'stop'. Returning it to 'neutral' gives 9mV).