[ICOM] power supply

[Harold Sullivan]

Thanks John for the info: I have come to the same conclusion on testing of 
components. I know that switcher power supplies can be strange in operation 
and a component that is out of spec won't let one of these poer supplies run 
right. I have a pretty good lcr tester and I will check further to see what 
i can find. I have loaded the 28 and 13 volts down a little thinking it 
might require some load to get started. No help in trying that before. I 
hope I can get it to run again. I know the radio is fine. 73, Harold


>From: John Hagle <jhagle at madbbs.com>
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>Subject: [ICOM] power supply
>Date: Sun, 07 May 2006 14:08:22 -0400
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>The power supply may need a minimum amount of a substitute load on the 
>28volt lines you have disconnected. Otherwise, the supply may shut down 
>even if you do get it to initially and momentarily power up. A couple of 
>resistors would do the job.
>
>I would recommend testing all electrolytic caps in the primary section of 
>the supply. These should be tested for value, and if you have the 
>capability, test for ESR-equivalent series resistance. If the caps are 
>okay, then look for failures in the solid state devices like transistors, 
>diodes, optical couplers.
>
>Good luck to you.
>
>73
>de N2JH
>
>
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