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All, I have a bad Silicon rectifier.. will replace with a 1N5408.. Question is do I need any additional resistance after the diode?
Here is schematic
[Image:
https://live.staticflickr.com/65535/5072...5bf7_c.jpg]
Thanks
Skip
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I take it that you were replacing a selenium rectifier? ( I see that you stated silicon, which is what your replacement will be?). I would see what the voltage is after the last filter, then add resistance if necessary.
"I just might turn into smoke, but I feel fine"
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(This post was last modified: 12-16-2020, 04:46 PM by
Phlogiston.)
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There is 27 ohms in place now to limit the charging rate of the first filter cap.
Pliny the younger
“nihil novum nihil varium nihil quod non semel spectasse sufficiat”
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The original rectifier is a selenium. If you replace it with a silicon rectifier you should increase R33 by about 100 ohms or add a resistor. You will want to check the voltage chart for the 12AT7 plate voltage and adjust the resistor value accordingly. If someone already replaced the rectifier with a silicon then put your new one in and check if a resistor was added. FM front end amps are usually sensitive to variations in B+.
(This post was last modified: 12-16-2020, 05:00 PM by
RodB.)