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. hey, TimmyTheTorch. I was trying to message you. I am trying to get my hands on more or these MOSFET RF output radios that people have thrashed on, and given up on repairing, so I can do some more tests n changes. Maybe get me a good repair customer base. I will send it back repaired. These...

my 5 cents worth (remember, todays inflation). I have a 142GTL that I got back on freq for SSB use. a "PI" made unit. date on the back.

yes, these amplifiers have "lame keying circuits." most of the amps I get, the RF key circuit is blown out, and has an attempt at repairing it. I put in a more robust circuit, that will not blow out.

I have a few of these 250's here. This RF key circuit has been messed with in both amps. One is keyed up all the time. I traced the diagram out and it makes little sense. So did this circuit ever work? AM and SSB? These amps seem to be OK. The transistors are biased, unlike many of these...

another thing on this radio set up. I got it after it was worked on before. It was blowing fuses. Regulator/mod transistor was all shorted out, and also found the short of a solder blob between solder joints at one of the IRF520's from drain to ground. I removed them 5.6 V zener diodes...

it is a "swing machine." that is because the meter on the radio is reacting to the positive going signal. so it shows swinging upward. but the overmodulated signal is also going to zero in the other direction. cutting off. going to no RF output. as in - "crank it up and whistle, then the...

Connex 3300HP Galaxy DX55HP circuit EPT360015C - I got my hands on a Connex 3300HP to repair. I see that many have problems with this radio, and all those other IRF520 MOSFET RF output section radios in general. - I only have worked on a few of these radios, to get them to work in SSB...

hey, hold off on your repair attempt. . . I have a Connex 3300HP to work on. I got it working, real good. but I noticed about 5.7 amps from the power supply during key up with 9 watts RF out. this is not good. and that "regulator" transistor got so hot, and it smoked and blew up!!! The...

well, now your radio is all screwed up. but you can set the IRF520 bias to 20 mA per device. as long as they are starting to conduct. but check the bias voltage adjustments. in SSB mode, mic turned off so no audio, no RF. with that mirror/shorting board in place, key up, and turn each...

I see the 010 schematic. about the same in the IRF520 RF output section, and has the 100k resistor ("C291") in the driver bias adjust circuit, so you can adjust properly. and again, in AM mode, with a dead carrier, with your 4 watts out, what is the voltage from TP7/8/9 to ground? should be...

so you have the IRF520 transmit section it sounds like? the "0015" board.?? "driver and finals adjusted to the correct ma" I was just working on a 2970N4, and on the main board, with the three IRF520 design, added the missing 100k ohm resistor so the driver bias current can be set. (I have...

me drinking some hot strong coffee all early morning here. but you probably have this: https://cbtricks.org/radios/galaxy/dx55v/dx55v_pll_adj.htm check the signal freq at TP-3 the PLL OFFSET OSC section. do you have a signal at IC-5 pin 2 ?? CB ch. 1 should be 2260 kHz the binary code...

Yes, sounds like PLL/VCO problems. I had a few radios just like this. to start: at IC-5 pin-1 check for around 7.5 volts. check the voltage at TP2 and measure if it changes when going from CB ch 1 and jumping to ch 40. check signal at TP3

I have this website bookmarked, on this DDS subject. from Brazilian guy.. https://www.ddsvfo.com/ .....

I have a 148GTL D MADE IN CHINA version that was given to me. It had drift problems, then one day it was stuck on one frequency. I have it working good now, from previous post on this forum. what version 148 do you have?

just happened in New Orleans the other day. https://www.wwltv.com/article/news/local/orleans/tesla-catches-fire-at-charging-station/289-8a9f5cb6-943c-484f-b406-2e34f194ed62 in New York City, and over the pond, careful of them e-bikes: Bradford fatal house fire started by charging e-bike...

hmmmm! I like working on these radios. these 2950/2970/2995 types. so where can I find this schematic for this board EPT6950016A on this radio? in case I get one to repair.

Yes, usually the "assclowns mods" are to disable the TX ALC, by turning it way off, or by cutting out the transistors/diodes in the ALC circuit, as was done on some Uniden HR2510's I was given. You can get by in AM with the ALC and AMC disabled, but in SSB it sounds super bad. I would set the...

First, I would put that shorting bar back in. key radio up in LSB/USB mode, no audio into MIC, and measure the voltage at either side of inductor L50 to ground and adjust VR20 and it should go up to .7 volts. it should be around .7 volts at L35 since the bias works on that transistor when...

oh, also on this "B" radio that looked like new, but had problems. it had that newer fat stock Cobra microphone. The element was bad. so no transmit audio. so I use an older "coffin mic" on it. I have found on a few other newer stock Cobra fat mics, (not sure if these mics have a nickname.?)...