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Old 8th Apr 2010, 5:09 pm   #14
julie_m
Dekatron
 
Join Date: May 2008
Location: Derby, UK.
Posts: 7,735
Default Re: HMV Mono Record Player Problem

Hopefully that can will be OK. Power up the player with a 60W filament light bulb in series with the live side of the mains (see here). If the bulb runs dim after about 5 minutes, it means the capacitors have reformed themselves; try connecting the player straight to the mains. If it shines at or near full brightness, there's a problem; in which case, you will have to replace the capacitors as follows:

Get two 47µF / 350V and one 10µF / 350V capacitors from your favourite supplier. Join all the negatives together, and connect to wherever in the circuit the common negative terminal came from (that'll be the 0V rail). Join the positives of the 47µF capacitors to wherever the positives of the 40µFs came from (probably the cathode of the UY85 and the screen grids of the UCL83 pentodes joined together), and the positive of the 10µF to wherever the positive of the 8µF came from (probably the cathodes of the UCL83 pentodes joined together).

By the way: The internals of this machine (as a rule, anything using U- or P-type valves) will be at mains potential, so take great care. Note also that the capacitors connecting the pick-up cartridge to the amplifier really need to be replaced with "Class Y" parts of the same value.
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