[Boatanchors] Cathode Keying Question

[Ed - K9EW]

Hi Lee,

Yes, you're absolutely right.  You need to key 120Vdc at 110mA.  A
reed relay would do it, but why not go 20th century, and use a MOSFET.
 Before you turn away, let me tell you that I've been keying my
boatanchors (both cathode-keying and grid-block keying) with the same
MOSFET circuit for several years now, and it's great.  You can buy a
little kit from Jackson Harbor Press (
http://home.att.net/~jacksonharbor/keyall.htm ) for $14.  There was
also an article in a recent (well, maybe in the past year) QST for a
similar circuit.

I invite you visit my website ( www.k9ew.us ) where I have information
on a BoatAnchor QSK project I put together.  You may get some ideas
from that.

73, and have fun with your project.
ed - k9ew
www.k9ew.us

On Mon, Nov 16, 2009 at 8:35 AM, Lee Buller <k0wa at swbell.net> wrote:
>
> I have a Knight T-50 and the VFO to go with it.  I am looking at making a TR switch that runs the VFO all the time while I key the T-50.
>
> I am a little flummoxed (confused) as to what the current and voltage is going through the cathode key of the T-50.  Unkeyed - the manual says 120 volts.  Keyed - the manual says zero volts.  Of course the the current keyed would be around 110 ma.  So, what I am working with here is 120 V and 110 ma at the key handle.
>
> Is my thinking right or am I off here?  Could a simple reed relay could handle these parameters?  The last time I did this was in 1965...and I used big old clunky relays.
>
> Lee Buller - K0WA
>
>
>
>
> In our day and age it seems that Common Sense is in short supply.  If you don't have any Common Sense - get some Common Sense and use it.  If you can't find any Common Sense, ask for help from somebody who has some Common Sense.  Is Common Sense divine?
>
> Common Sense is the image of the Creator expressing revealed truth in my mind. -  J. Wolf
>
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