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Pieter H · 7th Jul 2018, 10:53 am

I thin k the issue with the DR31/101 construction is the lack of a spring construction, it is a symmetrical arrangement, which is very tricky. Normal coil/solenoid-operated relays always have some form of a spring that pulls it to a neutral position in the absence of current through the solenoid. That's clearly missing in this arrangement and it will thus exhibit some form of sticking, also because it has to overcome the mechanical friction forces of the large switch assembly. I therefore still think, like I described in my earlier post, that the capacitor C65 that is temporarily put in parallel to the "target" solenoid is there to provide some resonance in an effort to overcome the "sticking".

Pieter

7th Jul 2018, 10:53 am	#71
Pieter H Tetrode Join Date: Sep 2017 Location: Waalre, Netherlands Posts: 67	Re: Decca DR101 dual standard TV I thin k the issue with the DR31/101 construction is the lack of a spring construction, it is a symmetrical arrangement, which is very tricky. Normal coil/solenoid-operated relays always have some form of a spring that pulls it to a neutral position in the absence of current through the solenoid. That's clearly missing in this arrangement and it will thus exhibit some form of sticking, also because it has to overcome the mechanical friction forces of the large switch assembly. I therefore still think, like I described in my earlier post, that the capacitor C65 that is temporarily put in parallel to the "target" solenoid is there to provide some resonance in an effort to overcome the "sticking". Pieter