ASRG blowing diodes

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Original poster: "MIKE HARDY" <MHARDY@xxxxxxxxxx>

I recently put a AR propeller gap on my 6", 4 kVA coil. It performs 
very well, Had some 9 foot ground strikes tonight. I run a 28V, 1.5A, 
3600 rpm dc motor. Powered by a 6A variac into a 120 to 24 V 5A step 
down tranny into a full bridge rectifier (20 A, 200V). This should 
easilly run this, and it did for many hours. Varying the speed really 
does some interesting things to the character of the streamers! I 
decided to run the 24 line to the motor thru some flexible conduit 
that I grounded to RF ground (in case of streamer strikes). After a 
short time on the 4th, it poped the 2 A slowblow fuse, then stopped 
all together. I found that half the bridge shorted, overheating the 
tranny some. Replaced the bridge, ran it for 3 hours (not hooked to 
the coil) at nominal line voltage, and all was fine. Ran the coil 
again tonight, and after a few minutes it blew again! Oh by the way, 
I didn't ground the flex conduit this time. How do others deal with 
this, is my problem unique?