There are a some reliable, and yet energy efficient techniques. If you can
stand
voltage drop, a simple series silicon diode is effective. If you can't stand
voltage drop and want to keep it simple, a big shunt diode (anode to ground
cathode
to plus input) and a supply fuse is effective. I use a 12 volt DC relay and two
small
silicon diodes. One is in parallel with the coil to absorb inductive kick, and
so
has anode to negative, cathode to positive. The other is in series with that
combination, anode to supply cathode to relay coil positive. Then if the
polarity is
correct, the relay gets power and I use its contacts to supply the radio.
Three ways, too simple for a kit. For my Corsair II I use an automotive cube
relay.
For the shunt scheme go for a 15 or 25 amp diode and the lowest current rating
fuse that will run your transmitter.
73, Jerry, K0CQ
---------- Original Message -----------
From: Noel <noel5856z@gmail.com>
To: tentec@contesting.com
Sent: Thu, 26 Nov 2009 17:30:19 -0500
Subject: [TenTec] Reverse Current Protection
> Hi...I'm looking for some practical circuits to protect a 12V 2A
> transmitter input. Are there any kits out there for sale?
>
> Thanks.
>
> Noel W1XB :-)
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
------- End of Original Message -------
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