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Cobra 138 23 Channel, SSB Manual

Bombardier

Member
Dec 19, 2021
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Hello,in need of the Cobra 238 23 SSB manual,need to allign,any help is appreciated. Thank you, have a great day.
 

Looks like it may be Sams CB-57.
I have the Sams book for that radio, I no longer have a scanner but i can try to take a clear photo of it and post it later on this afternoon,IMG_20220617_152034.jpgIMG_20220617_152104.jpg
 

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Last edited:
I can share one nugget of experience with that model. Never, never never adjust VR15, the sideband ALC for more than 3 Amps max draw from the radio's power supply. We learned the hard way to check for this before the covers go back on. Reason for this is the main T/R relay. It's built with thermoplastic that gets soft if you run the relay too hot. Causes the hot and ground sides of the relay's power-switching circuits to sag and short to each other. Pops the main fuse, unless it has a "no-blow" fuse. Then it pops circuit-board foil traces. The relay has a pretty strict upper limit of 3 Amps.

That relay looks like an american-made 'cradle' relay, but the pins are not arranged the same. A japanese-made relay is the only thing that will work in that radio. The pins on the american-made type will line up with the holes in the circuit board.

But it won't work.

73
 

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