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Excessive Field Coil Voltage in 70 ...
#6

Just wanted to share something I did with my 650. After getting it all restored electronicaly I installed a thermistor in series with the AC mains on a terminal strip under the chassis. This component when cold has a resistance of about 30-40 ohms. When the set is turned on the current draw warms it up and the resistance goes down to a few ohms. This allows a "softer start" to in-rush surge and drops the AC volts about 5 or 6 volts while operating with no reduction of performance (in my 650).
These were used most commonly in color TV degausing circuits in CRT sets.
I know some may think modifying the radio this way is not kosher, but I've repaired enough equipment over the years to know surge and heat is a killer. This helps with both. I also took the wisdom of the phorum and installed a line fuse on the same strip.

Dave Casazza
Keep em glowin and goin...


Messages In This Thread
Excessive Field Coil Voltage in 70 ... - by Guest - 11-23-2008, 11:21 PM
Re: Excessive Field Coil Voltage in 70 ... - by Guest - 11-28-2008, 01:14 AM
Re: Excessive Field Coil Voltage in 70 ... - by DCASAZZA - 12-05-2008, 04:05 PM



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