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Transmits OK on SSB but not AM

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Critter98
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Transmits OK on SSB but not AM

#411672

Post by Critter98 »

Hi all. I have a Realistic TRC-453 AM/SSB radio. Modulation is great on both SBs. Throws a great carrier on AM but no modulation. I haven't taken the radio apart yet and I'd like to know what I should look for inside.
Tks in adv.
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MDYoungblood
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Re: Transmits OK on SSB but not AM

#411687

Post by MDYoungblood »

It is probably the AM voltage regulator, usually located on the right side chassis, doubt if there are any replacements but there are plenty of donor radios at flea markets etc., so if it is in good shape, don't toss it.

3's

Greg
"321, West Manchester Township, PA"

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Critter98
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Radio: Realistic TRC-492 Navaho, TRC-453, Uniden PC68LTD, Uniden President Grant, 23ch Hi-Range 1 Hi-Gain
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Re: Transmits OK on SSB but not AM

#411705

Post by Critter98 »

Thanks Greg. I'll check it out.
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Critter98
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Joined: Feb 15 2024, 05:14
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Radio: Realistic TRC-492 Navaho, TRC-453, Uniden PC68LTD, Uniden President Grant, 23ch Hi-Range 1 Hi-Gain
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Re: Transmits OK on SSB but not AM

#411709

Post by Critter98 »

So if the 2SA3012 Resistor is what you're referring to as the AM Regulator, I checked that and it seems ok. PITA to take it out and put it back though. I've replaced 1/2 doz capacitors also but that changed nothing. Monday I'll be buying an ESR device that will test Resistors, Transistors, Capacitors & diodes. I saw a youtube guy using one and its a pretty simple operation.
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Critter98
2 PILL USER
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Posts: 11
Joined: Feb 15 2024, 05:14
Handle: 21 EW
Real Name: Dennis
Radio: Realistic TRC-492 Navaho, TRC-453, Uniden PC68LTD, Uniden President Grant, 23ch Hi-Range 1 Hi-Gain
Contact:

Re: Transmits OK on SSB but not AM

#411734

Post by Critter98 »

So after changing some more caps I've got the radio tx on AM now but it sounds fuzzy to the rx. I'll be changing more caps.
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