>QROers,
>
>My Henry 2KD Classic has developed an arc in the power supply. I'm running
>this by the group to tell me what I think I already know.
>
>The arc (observed in the dark) seems to go between the screw terminal on the
>top of the capacitor board and down the "hole" which I think is provided for
>the vent in the capacitor. It appears that some white material was present on
>the top of the capacitor at the vent. I will be removing the board to examine
>it, but I just wanted to have the failure of the capacitor confirmed.
>
/\ White material around the vent means that a cap. has went.
>Any tips on removing the board? It appears that once the screws are removed
>from all the caps, the board will come out.
>
>Should I just get a replacement from Henry or should all the caps be
>replaced?
>
/\ Since they are in series, all the filter caps. should be replaced.
- Henry Radio has the habit of using relatively low-R equalizers on
electrolytics. For instance, the Henry Radio 2KD-5 uses 25k-ohm, 25w
resistors for equalizers - mounted next to the capacitors. These
resistors become quite hot. This subjects the capacitors to high heat.
For every 10-degree C increase in temperature, the life expectancy of an
electrolytic cap. is cut by 1/2.
The fix is to decrease heat by changing from 25k-ohm to 100k-ohm
resistors - and to use 105-degree C electrolytics.
º
cheers, , Mark
- R. L. Measures, 805.386.3734, www.vcnet.com/measures.
end
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