[Heathkit] SB 220/200/201 Amp standby mode?

[Peter Markavage]

Go to a flea market or an old radio/TV service shop. Find a volume
control with a push/pull switch on the back. Control should have a
threaded bushing on it so that you can secure it to the front panel.
Remove the sensitivity control from the front panel. Put this new control
and switch in its place. Wire up the control leads as on the old control.
Break one of the leads going to the antenna relay and wire the switch to
the two broken leads. Put the knob back on the shaft. You're done.
Control resistance for the pot doesn't have to real close to the
original. On most switches, pull out of the switch connects the two wires
from the antenna relay making the amplifier on line. Push the switch in,
antenna relay becomes inactive, and contacts on it just act as pass
through for the RF from the exciter.

If you don't care about diddling with the sensitivity control each time,
and ordinary volume control type pot with an on/off switch with do the
same thing. Turning the control full counter clockwise, activating the
switch, will put the amp in standby. Turning the control clockwise, to
activate the switch will put the amp in active mode.

Either way, it's one of the simplest modes you can do to the SB-200/201,
etc.

This info has been documented several times on various QSL.net
reflectors.

Pete, wa2cwa

On Tue, 11 Jul 2006 10:40:28 -0400 "Richard Franzson"
<Franzsrf at umdnj.edu> writes:
> Everyone,
> 
> Thank you for your responses to my question. I guess that heath 
> never
> thought of installing a standby switch when they designed these 
> amps.
> 
> 73,
> Rich KE2VM
> 
> >>> Rick Brashear <rickbras at airmail.net> 07/11/06 10:35 AM >>>
> Hi Rich,
> 
> I also have a 221 and I devised a small relay and switch to open and 
> 
> close the keying circuit from the transmitter to the amplifier.  
> There
> 
> are many mods available to accomplish a "standby" mode for the 221.  
> 
> Maybe someone knows if they are all centrally located and can give 
> you
> 
> the address.  Of course, you can always use coax switches to by 
> pass
> the 
> amp entirely when not needed.
> 
> 73,
> Rick/K5IZ
> 
> 
> Richard Franzson wrote:
> 
> >All,
> >
> >Just for curiosity, when these amps are tuned up and ready to run 
> at
> >the power level you need for that extra dx pileup punch through. 
> And
> you
> >are finished running at 1kw to make the contact. 
> >What can be done to have the amplifier be on standby to run only 
> the
> >transceiver at it normal power output? Then bring the amplifier 
> off
> of
> >standby, to use the amplifiers power output when you need it.
> >I have a SB 201 I just bought and I did not see a standby switch 
> on
> the
> >amplifier to keep it powered up when I don't need the amplifiers
> extra
> >boost for dx.
> >
> >Tnx,
> >Rich KE2VM