• You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.

General Lee No Output

Low_Boy

Sr. Member
Jan 21, 2010
1,931
1,193
173
Rochester N.Y.
Started out with blown TR43 last final before antenna. Replaced TR43. TR44 Driver was good and TR46 first final was good. I replaced all three for good measure. TR45 pre driver checked good. TR46 RF Buffer Amp checked good. Although all voltages for finals and drivers are not listed I was able to check all voltages they seemed good and was able to adjust gate voltage as per. CB Tricks Galaxy 33 HP. So when the mic is keyed TX light changes but no output. I get a bit more ripple on sope if touching the collector of pre driver (TR45). What have I missed?
 

Getting a week signal that can only be picked up with a oscilloscope signal is on frequency. Shows strongest at collector of pre driver. but cat be seen as far as the antenna socket.
 
Checked all that. Turned out to be TR51. Don't quite understand though. Why would the modulation amp not let the radio key? That is why I asked the question what other purpose does TR 49, 50 and 51 do. I got suspicious last night when the voltage on those three components were off. And TR51 was the last component checked.
Thanks Robb
 
  • Like
Reactions: kaos513 and Robb
In AM mode TR51 is the modulator and carrier-control regulator, both. It controls the steady DC voltage that sets the carrier power, and also amplifies the mike audio, 'modulating' it onto that DC voltage powering the driver and finals. Textbook term for this is "high-level modulation". Snobs will call it the brute-force method of AM modulation.

In radios with sideband modes, TR51 is a switch. Feeds full-bore DC voltage to power the driver and finals.

In older SSB CB radios, the mode selector would be used to switch the power to the finals and driver between the AM modulator and full voltage for sideband. In a SSB model built with this circuit board, TR51 does both jobs.

RCI, the vendor who builds this radio chose to use the same circuit board for radios with SSB and for radios with only AM and FM, like this one. You'll see numerous empty outlines printed on the board with empty holes where the sideband parts go in those models. In a G. Lee or Connex 3300, or Galaxy DX33, the sideband parts are simply left out.

73
 
I am having a issue with a gen lee tr51 keep blowing its blown 3 of the same part it had a swing kit with a toggle that was remove and everything put back to stock and it still blows the part would could be the issue
 

dxChat
Help Users
  • No one is chatting at the moment.
  • dxBot:
    Tucker442 has left the room.
  • @ BJ radionut:
    LIVE 10:00 AM EST :cool:
  • @ Charles Edwards:
    I'm looking for factory settings 1 through 59 for a AT 5555 n2 or AT500 M2 I only wrote down half the values feel like a idiot I need help will be appreciated