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First thing I check is to unplug the two-wire lead that serves to key the amplifier in the rear. Need to know what power the barefoot radio delivers before looking deeper. Got a pic of that somewhere. I'll see if I can find it. 73

IC501, the IR2429 driver chip for that display has a charge pump circuit in it. Uses three electrolytic caps C501, C502 and C503 for this. If one of them is installed reversed, it would reduce the voltage feeding from the charge pump to the LCD. Years ago the dot-matrix LCD displays we used for...

No need to be charitable. YT is filling up with BS channels like this. Lost track of how many times the Three Gorges Dam in China has collapsed. 73

12 Volts DC. Will be happy enough with 13.8 Volts from a power supply meant to power a radio. Can't remember the polarity of the coaxial power socket's center pin. 73

Pretty sure that's the location of the external speaker jack when this circuit board is used in a mobile model. Since the external speaker jack is on the rear panel away from the circuit board, this jumper is probably legit. 73

And there is a city ordinance in Ocean Springs Mississippi that prohibits landing a UFO in the city limits. Seems too many of the city fathers had kin being abducted. 73

The factory power supply in that radio was suicidal. Typical failure was a shorted pass transistor in the regulator circuit. Would cause 22 Volts DC or more fed to the radio circuit board. Might want to check that before powering it up for longer than it takes to get a meter reading. Poofed...

Original post is from January 2019. Sure do hope he got it fixed in less than six years. 73

No capacitor in this one, just the variable inductor. Gets placed in series with the 10.6975 MHz carrier crystal. 73

I suspect what you're looking for is Q114. It's the transistor that has its collector shunted across the mike audio feeding into the mike amp. It's just to the left and rear of IC104, the mike amp near the front-center edge of the main pcb. There are other ways to disable Q114, but if it's...

Won't be long before junkyard parts are your only choice. That part isn't being used in any radios currently produced. It will slowly dry up, starting with the legit suppliers like Barkett. Sure would be nice if someone (else) were to reverse-engineer the specifications for the slug-tuned...

That was the unique genius of Ralph's solution for the 858 chip. Wouldn't work on anything else. But it took care of the "jump" the PLL's output frequency would do between transmit and receive on AM. Makes the usual VCO-input displays jump 3 kHz when you key the mike. Would not change in step...

Not familiar with that one. The digital S-meter is still being fed from an analog voltage out of the receiver detector circuits. RCI radios that use the bar-graph S-meter in a mobile model are also made with an analog meter in other models. Same main circuit board, different meter hookups. The...

Looks like a factory bodge to me. The Superstar SS158 schematic shows the diode and cap like this in the band select circuit. Probably only needed for a 12-band radio, and not a 6-band version made with the same pc board. 73

It's the choice of the tap-in point that determines if the clarifier affects the displayed frequency. The frequency feeding into pin 11 of the PLL doesn't change from one mode to the next. Same deal with the clarifier. The frequency fed into the 858 PLL chip isn't affected. Only the frequency...

If it's the version I'm thinking of, it only has 5 digits. Try pin 11 on the uPD858 PLL chip, or the collector of TR31. If I'm wrong it will just display nonsense. 73

Pretty sure the Mongoose radio sold by shiny-metal electronics in the 90s is also the same. The vendor is a korean outfit whose name translates to "Dragon". Can't remember what their korean name is. Seems to me there was at least one other name/model for that radio design. Don't remember what...

Loaded my TS-530 into my White Lightning clone quad on 3675 one night. The radio's internal tuner helped. The 27 MHz series-fed driven element must have looked like about 5 ohms. Should put an analyzer on it one day just to see. The other folks on the sked that night heard me, but not all that...

It's probably the most narrow-banded antenna you can use on HF frequencies. Reminds me of the 18-inch long center-loaded Hustler CB antenna of the 70s. Was commonly mounted on a rain-gutter clip. Remember rain gutters? That antenna would tune to a 1.3 or so at resonance on channel 12 and rise to...

All the Galaxy/RCI displays like this that we bought came with that socket and a wire harness. Meant to be wired into your radio. Or you could buy one from us on fleabay. Finally found the sack of leftover sockets that piled up when we were installing the guts of the FC390 into Siltronix VFOs...