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Vintage Realistic CB Base Radio

well all i can do is help add to the confusion.

here is a PCB layout from the service manual for the TRC-449 that Nomad provided to CBtricks (as always thank you nomad).

1754970869521.png

looks like the top resistor holes have nothing, the two below it have resistors installed, and the diode marking has a jumper.

oh look! the holes for "C402" have a 1 watt resistor installed there lol.

i have no idea whether or not these parts are actually installed in a TRC-449 or if there are wires that go other places.

looks to me like the idea was to provide some generic "anchor points" for features not envisioned yet.
LC
 
loosecannon said:
well all i can do is help add to the confusion.

here is a PCB layout from the service manual for the TRC-449 that Nomad provided to CBtricks (as always thank you nomad).

View attachment 73790

looks like the top resistor holes have nothing, the two below it have resistors installed, and the diode marking has a jumper.

oh look! the holes for "C402" have a 1 watt resistor installed there lol.

i have no idea whether or not these parts are actually installed in a TRC-449 or if there are wires that go other places.

looks to me like the idea was to provide some generic "anchor points" for features not envisioned yet.
LC
Click to expand...
When the silkscreen shows a circle around a thru hole and a line protruding from that to the other thru hole, doesn't mean the component is left out or jumpered, but the device is instead installed on end.

nomadradio said:
The solder pads that look like an open-end wrench are for external wires. As if some additional switch or control was connected there. Don't know what for, though.

73
Click to expand...
Bingo.
 
Cable Guy if i understand what you're asking correctly, i believe that circle indicates the body of a vertically mounted resistor and the line is the lead coming off the top.
LC
 
They don't trace out to anything. The node at R196 goes to the TX supply switch. Three of the resistors go to ground and the other resistor floats. They are not associated with any other circuitry in the radio other than the TX supply.

What kind of switch requires TX only power and various load resistors to ground?
 
I thank all for your participation in my curiosity of the section of board that is silk-screened but lacking components on the 457 board. There is no transmit indicator light on the 457 but there are bulbs located in each of the two meter housings.

I have attached the SAMS schematic for the incandescent bulbs that are used for the two meters in the 457.

Ft1NXLP.jpg
 
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Is it actualy off or are you not accounting for the freq. offset when looking at a freq. counter between the AM freq. and the coresponding offset of freq for upper and again for lower side band?

I ask because I am not on often enough to recognize everyone and what everyone already knows. So compared to AM yes they should be offset.
 

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