[AMRadio] Transformer Rewind

Geoff/W5OMR ars.w5omr at gmail.com
Sun Dec 16 13:44:29 EST 2007

jeremy-ca wrote:
> The input coil is common to all bands in the 75A1, the secondary is 
> then fed to the band switch.
> Check the antenna coil primary first and then the secondary for 
> continuity. Rewinding shouldnt be that hard if the form hasnt been 
> destroyed. The hardest part will be removing it from the assembly.

A couple of decades ago, I accidently dumped a few hundred watts of RF 
directly into the front-end of an SX-73, on 75m.  The input coil took 
the brunt of the damage.

John Mohn/W5MEU(sk) told me to come out there and get some 24ga copper 
wire to re-wind that coil.  Very carefully, I removed the phoenelic 
board from the turret in which the coil was installed, then ever 
so-much-more carefully, removed the coil from the board.  There was a 
spot on the coil that -wasn't- burnt, so I was able to count turns, and 
re-wind the coil.  Luckily, I was working at Southwest Research 
Institute at the time, and was able to utilize a small-wattage iron, 
some organic stripper and a magnifying glass to re-solder the connections.

Driving your AM Rig without a scope, 
is like driving your car at night, without headlights. (K4KYV)

73 = Best Regards,

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