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Old 06-21-2019, 03:40 PM
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Tom Albrecht Tom Albrecht is offline
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The end of the resistor body with the stripe is the + end. Start with about 50 ohms, at least 5 watts, and adjust from there. Sets with voltage doublers for the main B+ need a smaller resistor (typically 10-20 ohms, 10 watts) but I believe in this set that rectifier carries a smaller load. The added resistor simply goes in series with the diode, either before or after.
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Old 06-21-2019, 04:35 PM
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M3-SRT8 M3-SRT8 is offline
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There are, obviously, two leads connected to the selenium rectifier. One to the positive marked end, and one to the negative. I take it the diode connects in similar fashion.

Does the 50 ohm resistor go between the negative lead to the diode or the positive?

Thanks.

PS: It's been awhile since I've done this.
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Old 06-21-2019, 06:22 PM
old_coot88 old_coot88 is offline
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Dumb as it seems, the '+' end of the selenium corresponds to the banded (cathode) end of the Si diode. The + sign simply means "the B plus comes out of here".

The resistor would connect "upstream" of the diode.
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Old 06-21-2019, 07:07 PM
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Tom Albrecht Tom Albrecht is offline
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Quote:
Originally Posted by Tom Albrecht View Post
The end of the resistor body with the stripe is the + end.
I should try proofreading some time.

The end of the diode with the stripe is the + end.

The added resistor goes on either side -- it doesn't matter which you choose.
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Old 06-21-2019, 07:38 PM
old_coot88 old_coot88 is offline
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Which side doesn't matter, but conventionally it went on the input side of the diode.
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