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Old 08-20-2010, 05:53 PM
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Bill Cahill Bill Cahill is offline
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Quote:
Originally Posted by jr_tech View Post
By not using the 5V 2A winding you lighten the load by 10 watts... also the 6.3 of the RCA transformer is 9A, while the DuMont is designed for 7.4A, so that winding will not be running at full load, another 10.1 watts lightening of the load.
The additional draw at 770V from .240A to .260A is only 15.4watts, so the transformer could actually run cooler. DuMont tended to over-design, so the actual current draw in the B+ may be somewhat less than 260ma.
I would consider adding a couple of plate resistors in the 5U4 plate leads or one resistor in series with the input choke, to drop the extra 10 V.
Are the dimensions/bolt patterns similar?
jr
Don't connect your damper to six volt line!
You'll blow entire set!
That has hv pulse on it!
You MUST use that five volt winding the original used.
Bill Cahill
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