On Mon, 2009-06-08 at 16:31 -0400, Mike Hyder -N4NT- wrote:
> Couldn't find my slipstick but cipherin' it on paper gave the following
> values:
>
> Current for full dissipation (50 w) = 18.26 Amps
>
> Voltage drop @ 18.26 Amps across 0.150 Ohms = 2.74 Volts
>
> This causes me to wonder if a properly rated fuse wouldn't work as well --
> perhaps a 15 Amp 3AG fuse?
Maybe, except the reason for the resistor is probably to make power
transistors share the load for thermal balance and the metal in a fuse
is likely to not be very temperature stable.
73, Jerry, K0CQ
>
> 73, Mike N4NT
>
> ----- Original Message -----
> From: "Harry Coates" <wa8hc1@charter.net>
> To: <tentec@contesting.com>
> Sent: Monday, June 08, 2009 11:37 AM
> Subject: [TenTec] Kinda OT
>
>
> > Hello to all, This is kinda off topic.. I'll put it on topic.. I use my
> > Pegasus for portable operation when camping..
> >
> > I use the internal 12v system in the camper from the battery side for a
> > power supply.. The battery charging part of the converter quite working..
> > I found the problem, the big ballast resistor went open.. It's one of
> > those big white ceramic 50w .150 ohm units..
> >
> > You just can't find those thing at the corner store..
> > Why do these manufacturers choose them?? Something I don't know?? I can
> > get a 50w 1 ohm
> > old brown wire wound one.. That should work..
> >
> > Camping season is upon us up here!!
> >
> > (TEN TEC FOREVER AND RTTY TOO)
> >
> > Harry
> > WA8HC@ arrl.net
>
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