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Vintage Television and Video Vintage television and video equipment, programmes, VCRs etc. |
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13th Sep 2021, 12:59 am | #21 |
Dekatron
Join Date: Apr 2019
Location: Worthing, West Sussex, UK.
Posts: 6,587
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Re: Sony AV3670 Head motor starter capacitor
I have now seen the manual.
There is no mains frequency changeover switch, the changeover is done at the board that the dual capacitor fits into (C Board). The wire connection at the 1.2uF goes back to function switch SW008 so does need to be left connected. Page from the manual attached. David |
13th Sep 2021, 9:32 am | #22 | |
Moderator
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Re: Sony AV3670 Head motor starter capacitor
Quote:
I suggest you purchase a 3.6uF or 3.7uF capacitor |
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13th Sep 2021, 10:46 am | #23 |
Dekatron
Join Date: Apr 2019
Location: Worthing, West Sussex, UK.
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Re: Sony AV3670 Head motor starter capacitor
At Post 8 you measured 2.6uF at the dual capacitor terminals which should have been the paralleled combination (if measured at C Board with joining track not cut for 60Hz operation).
Have you measured (2.5 to C and 1.2 to C) on both capacitor sections since removing the dual capacitor ? There of course is the possibility that the motor itself may have gone defective, less likely though. David |
13th Sep 2021, 11:05 am | #24 |
Dekatron
Join Date: Apr 2019
Location: Worthing, West Sussex, UK.
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Re: Sony AV3670 Head motor starter capacitor
Have you checked the 800mA fuse F007 at the FU Board, this feeds 100VAC from the power transformer to the main motor via the Shut off Tape in switch S007 & Stop switch S008 ?
David |
14th Sep 2021, 4:09 pm | #25 |
Pentode
Join Date: Oct 2016
Location: Ware, Herts, UK
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Re: Sony AV3670 Head motor starter capacitor
Hi all. Problem appears to be fixed now.
For all of you stating the UK 50Hz model needed a 3.6/3.7uF starter/run cap - you were correct. So, the original Sony cap does appear to have failed. My confusion was how Sony "added in" the extra 1.2uF cap to the circuit. By assuming it was via the lead attached to the 1.2uF terminal it sent me down the wrong path. Not clear - even on the attached pic here (of the board Sony provided in the original machine to connect the capacitor to the circuit) , there is a track joining the 2.5 and 1.2 terminals, thus creating a parallel circuit and the 3.7uF cap across the motor. By joining the 2 replacement starter caps in parallel and connecting back up, the motor now starts to the correct speed everytime. @Michael Maurice - I assume you are referring to my 1.2uF Fan Motor cap. This solution is working at the moment - and I can only see 3.5 or 4uF alternatives as a single cap. What is your concern as to what might happen? |
14th Sep 2021, 4:26 pm | #26 |
Dekatron
Join Date: Apr 2019
Location: Worthing, West Sussex, UK.
Posts: 6,587
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Re: Sony AV3670 Head motor starter capacitor
Yes the board as shown in Post 21 attachment.
Do you have any data on your new 1.2uF fan motor capacitor ? I have no idea what your motor is like, i.e. is it fairly heavy duty ? David |
14th Sep 2021, 4:34 pm | #27 |
Octode
Join Date: Dec 2008
Location: Wincanton, Somerset, UK.
Posts: 1,757
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Re: Sony AV3670 Head motor starter capacitor
If your fan cap has a voltage rating, make a note.
Then carefully measure the ac voltage across the caps when the motor is running. If the latter is well below former, you should be fine. John |
14th Sep 2021, 4:39 pm | #28 |
Pentode
Join Date: Oct 2016
Location: Ware, Herts, UK
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Re: Sony AV3670 Head motor starter capacitor
As requested,
The fan starter capacitor is rated at 450VAC. The motor runs off 110VAC. Do you think this capacitor (when combined with the 3.5uF starter cap from post 4) is indeed safe to use? Many thanks all. |
14th Sep 2021, 6:59 pm | #29 |
Dekatron
Join Date: Apr 2019
Location: Worthing, West Sussex, UK.
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Re: Sony AV3670 Head motor starter capacitor
I would say yes.
The CBB61 are spec'd for continuous use as a motor run capacitor and are Polypropylene and the 450VAC rating is good (note the voltage across the motor split phase winding will be somewhat higher than the 110V supply (100V shown on schematic). Some more inferior fan capacitors may not be that suitable. I have used the CBB61 myself on tape recorder motors without issue. David |