Panasonic/Technics RS-858 - Poor Fast Forward Performance

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macdude

Active Member
Joined
Mar 13, 2008
Messages
60
Location
Pittsburgh, PA
For years I've had this unit and was very unimpressed with it's fast forward performance. Recently, while working on it, I noticed the FF switch enables a second winding in the motor with a 47ohm current limiting resistor. I've seen schematics that show both a 47 ohm and a 33 ohm resistor in this position. Out of curiosity I switched in a 33 ohm. Fast Forward was greatly improved. Before you hardly noticed an RPM change. Now it seems to work as it should. Faster, yet not incredibly fast (typical of 8 track fast forward modes). Just a note I thought I'd share. The resistor is rated for 2 watts. This applies to the 13.2VDC motor with red/yellow/blue leads. The yellow lead is the FF winding.
 
Just out of curiosity, Did you happen to notice the condition of the grommets on the motor? I have two of these decks and 3 of the model that only records in stereo and the grommets are shot in all of them. I have not been able to find an easy source to get them from.
 
I replaced mine with standard size grommets from the hardware store (ACE / True Value) with the little bins. If they're not tall enough, a few neoprene washers should make up the difference.
 
Just out of curiosity, Did you happen to notice the condition of the grommets on the motor? I have two of these decks and 3 of the model that only records in stereo and the grommets are shot in all of them. I have not been able to find an easy source to get them from.
Hi - zombie thread but may be of use to someone - I used Rockola jukebox turntable grommets, easy to find on eBay (or search Thorens TD-124).
 
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