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04-25-2019, 10:47 AM   #316
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QuoteOriginally posted by photogem Quote
Next time I have a K30 or similar open, I shall check this. I only checked in M-Mode and my guess is that whenever an A-lens is not in A-position, the solenoid is not engaged at all.
It isn't engaged in M-Mode for sure, this I have verified.
With modern lenses (no aperture ring), I can confirm (K-S2) that the green solenoid causes problems in M mode just like in Av mode. I didn't observe its state/operation directly though, just noted that replacement with white solenoid fixed the issue reproduced in M.

04-26-2019, 12:38 AM   #317
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This is different.

You need manual lenses which allow you to set the value of aperture on the lens!
04-26-2019, 08:43 PM   #318
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RayeR, it looks to me like this is not a PWM solenoid because the line is flat; is that correct? What is the voltage on the flat yellow line and what is it on the push line? What does it drop to at the release point? I found on TLX Technologies website some solenoid theory articles. It said polarity is important on latch solenoids as a permanent magnet holds the armature and reversing the polarity either strengthens or weakens the magnet. From the graph it seems that this solenoid just latches and unlatches and is not proportional. Is this correct? Or does the push line vary according to aperture opening? This is most helpful.
04-30-2019, 05:11 AM   #319
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QuoteOriginally posted by slartibartfast01 Quote
Thanks I always wondered about that. Does the same apply to Optical Preview ?
I didn't see this question of yours:

I have to check next time one of those cameras with a jammed solenoid is on my worktable.
Never checked this before.


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