[ARC5] Switching the dreaded B+ line.

[Leslie Smith]

Good-day all,

I wish to build a control box to switch the B+ line to the PA and
oscillator circuits in the same way that the selection relay (I think
it's K-53 or relay 53) does.   (This is for a BC-457 - soon to become a
BC-696 ... or a pseudo BC-696 ... )   

But what if  relay K-53 has been "pilfered".  Hmmm?  What if I want to
have a control box with a 3 position switch,  "Spot, Receive, Transmit"?
  That would be a useful switch to have on a control box.  

I could, of course, use a relay, wired in the say way as K-53.

OR (this is such a clever idea I can hardly believe *I* thought of it
...)  I can use an enhancement P-Channel MOSFET in place of the relay.  
 I looked in all the usual places and found nothing over -600V and
nothing under $10.oo    Nothing?  Really?  Seems I didn't look very
hard.  Hmmm.  I have tubes full of 900V 5A N-Channel MOSFETS here, but
I've never had the need for a P-Channel device.

Any ideas?  Hmmm?


Les

PS.  I've given up looking too hard.  Last time I looked for something,
(it was the SCR-274 manual) I looked for about 2 1/2  hours.  Nothing.  
Grrrr!   Then I asked here, and bingo!  In less than 5 minues Jim McVey
gave me a link!!  (Less than 5 minutes!!!)    Miracle!  The very one I
wanted!!   

Now we all know Jim is a nice fellow, but why did he have to wait until
I asked?  Why couldn't he just tell me, before I wasted 2 hours?  Jim?  
Hmm?  (Life is very difficult, I think ...)

(Maybe I'll use a PNP pibolar HV transistor switch.  Except no-one makes
pibolar.   Oh, I get it!  I'll use bipolar. )