[K3PZN-List] UHF repeater repaired (Andy Leeds)

[Philip Karras]

I see the fuses did their job, to protect the wires & in this case the connectors, not!

You might look the system over to find out why the fuses did NOT do their job, it could be worse next time. Perhaps they only look like fuses? They didn't act like fuses, best to replace them & then play with them as time permits.

Good work!, My inclination would be to replace all difficult power connectors with Anderson connectors & be done with it. You might buy different colors for the different voltages.

73 de ke3fl
Phil

> Message: 1
> Date: Sat, 13 Aug 2011 18:16:35 -0400
> From: Andy Leeds <wo3l at comcast.net>
> Subject: [K3PZN-List] UHF repeater repaired
> To: Carroll County Amateur Radio Club <k3pzn-list at mailman.qth.net>
> Message-ID: <4E46F7C3.6080305 at comcast.net>
> Content-Type: text/plain; charset=ISO-8859-1;
> format=flowed
> 
> I finished repairing the UHF machine today. Turns out C817
> on the 
> repeater's control shelf which is a filter cap across the
> 9.6V input 
> dumped its guts and shorted. In a sane world the
> corresponding fuse 
> would have blown. In this case it did not. Further miracles
> occurred and 
> the 9V regulator actually survived the dead short on its
> output. One 
> would now expect the fuse on the A+ line to be blown but
> those were OK 
> as well. After hunting around a bit it suddenly hit me - if
> the fuses 
> are good but there was a dead short something else had to
> give along the 
> A+, sure enough it was the connector taking the A+ from the
> PS to the 
> repeater's intermediate PA board (the 9V regulator is
> actually located 
> there). The 2nd A+ pin (there are 2 x 4A connections) was
> charred 
> completely. The funny thing is it still made enough contact
> that when 
> the load was disconnected I saw good voltage down on the
> end of the 
> cable. If I connected any sort of load the voltage dropped
> to .5v or so. 
> I made a jumper between the 2 A+ lines up at the PS
> connector to solve 
> the problem (lovely odd connector up there) until I see one
> of these 
> connectors at the hamfest.
> 
> Andy
>