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My
question is if I have a power supply that is not putting enough voltage will that effect my radio where I cannot transmit, my friends say all they get on the other end is a buzz noise, and I notice that the lights on my display go dim when I transmit. Dustin, this should have been covered in the theory which you studied for your exam. The radio requires a certain voltage (most likely 12.9 to 13.5 VDC) and CURRENT. If you have a radio which is supposed to output 25 watts, an easy rule of thumb is to triple the amount of watts (75) and divide it with the input voltage. For example, the old RatShak I used mobile for some years was 25W out..divide 75 with 13.5 VDC gives me approx. 5.5 amps needed for xmit. Now, as the rest of the circuitry, lamps, etc draw some current, lets round it up to 6 amps. The supply would have to output around 6 amps with no "sag" in voltage to properly run the rig and give some leeway. This is very simplistic...and only a quick "SWAG" method of looking at current requirements. Your manual should give exact specs on your rig. I'd bet (esp. with the "buzzing noise"....60 cycle noise due to poor regulation in the power supply) that the P/S is either too low wattage, in need of new filter caps, or both. To get on the air, try a 10 to 17 aH 12V GelCell and use the P/S to charge the battery. The GelCell will output enough current to run the rig, and the "power supply" can charge it. Don't leave it connected all the time to the power supply, though. Overcharging can damage the battery. A better solution is to either rebuild the power supply (if the transformer can output enough current to run the rig) or buy a commercial unit, such as an Astron RS20. WATCH OUT FOR POLARITY!!! It is painful to watch smoke come out of your radio..... I think you have a chance to get some "hands-on" time here, and maybe even build your own power supply! It is fun, and then you have the right to say that you're using something you built with your own hands....very satisfying, at least to me. Today, so few folks can say that they even know what goes on inside the "boxes" they own.....personally, I enjoy tinkering. Lots cheaper than therapy, and I get new toys when I do it right......! Cheers; A |
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