> >Hello everyone, I just got a SB-200 for my Elecraft K2/100
> transceiver. Can
> >anyone tell me what I need to do to make this amp work on my
> transceiver?
> >Also, what mods are "must have" for the SB-200
>
> If I bought a SB-200, I would:
> 1. Change it from negative-V RL-Control to positive.
> 2. Remove the cockamamie, not-standard R/T bias arrangement and orig
> relay.
> 3. Add the high-speed switching mod so it won't hotswitch with modern
> transceivers.(c.$60)
> 4. Use the orig relay to add stepstart. (c. $4)
> 5. If new 572Bs are to be installed, improve VHF stability. (c.$13)
> >
Agreed. Before I got the SB-220 I owned an SB-200. I looked at AG6K's QSK
mod for the SB-220 and modified the SB-200 to use it. With the Matsushita
relay for input switching and the Jennings RJ-1A for output switching
there's just nothing like it. It's so quiet you'll wonder why you ever put
up with the old clunky relay. There's a handwritten schematic at:
http://64.40.84.76/doug/misc_stuff/sb200_s.jpg
and a higher resolution scan at:
http://64.40.84.76/doug/misc_stuff/sb200.jpg
I don't show all the SB-200 details, just the stuff that differs from the
SB-220. You should start by reading the SB-220 QSK writeup at AG6K's site. I
didn't use electronic bias switching, and I didn't convert to a positive
relay control voltage, but if your rig has a noisy keying relay or one that
can't handle the voltage then you probably should.
73,
Doug, K4DSP
|
