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Looking for a tech to fix a couple amps...?

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714sandman
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Looking for a tech to fix a couple amps...?

#400949

Post by 714sandman »

I have two amps that need going through. First is a Loudmouth 1X3 using four 6LF6 tubes. The tubes test good on a B&K 747. The relays aren't working properly and the receive preamp wasn't working right either. I put a brand new transmit relay in and, alas, no love. I love old tube stuff and this one working properly is my FIRST PRIORITY.

I also have a Palomar Red Devil 350HD. That one had a blown electrolytic and two cooked resistors. I could not find a schematic for it but I changed out the resistors with a "best guess" based on a scheme for a similar amp. It "seems" to be working but I want it checked out anyway.

I am in Southern California, Orange county to be precise. I would like to find someone close by to save on shipping which is very costly (and risky). I don't mind sinking some money into these things but I am not investing either :lol: otherwise I'd buy something new and be gone with these two, so fair pricing is a must. I got a bit of sentimental reason for wanting these guys working (especially the Loudmouth). Any referrals? I have a bunch of ham gear, tubes, and other stuff I could trade up for work, or cold hard cash is fine with me.

ANYONE come to mind within 75 miles of Huntington Beach CA...?
Thanks for your help!
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MDYoungblood
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#400969

Post by MDYoungblood »

My best suggestion is to get on the radio and talk with others that know someone around you, they are there, but good garage/basement tech's aren't going to do any work if they don't know you. Run what you got and get on the air.

3's

Greg
"321, West Manchester Township, PA"

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Monk
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#407325

Post by Monk »

Hi Sandman,

Check the keying transistors and the pre amp transistor. The part numbers are stamped on the transistors and they
are cheap. If replacing the transistors doesn't fix the problem there is a low voltage supply to run the relays ~12 volts. It is usually a single diode off one of the taps from the transformer followed by a electrolytic capacitor around the value of 470~1000 Uf at 16 volts. The diode can go bad or the cap short thereby leaving the relays without power to run on.

Monk
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