[Kenwood] SM-220 or 230

[Bryan Swadener]

Hi Leo,

I stand by my statements.  Per the SM-220 service
manual, when equipped with the BS-8 adapter, it will
work with an IF of 8.830 MHz.  Though the service
manual says only "TS-820 series", this would include
the TS-850 or any rig which shares the same 8.830 MHz
IF.  It also works with my TS-120S and TS-130S rigs
(also 8.830 MHz IF) -- all I needed to do was
fabricate a simple buffer amplifier, mounted near the
mixer output.  It's easier w/ the TS-850 since you
don't have to open the box.  According to the service
manuals for the SM-220 and SM-230...

SM-220 Input Sensitivity = "More than 20 dB/uV"
SM-230 Input Sensitivity = "More than 20 dB/uV"

So, since the SM-230 will work with the TS-850, the
SM-220 (equipped w/ BS-8) will also work with it.

Funny thing -- I don't care for the SM-220 as a
spectrum analyzer.  For a couple of reasons, I prefer
to use my old Heath SB-620 -- it has a longer
persistence phosphor CRT, and the scale is more
appropriately marked for spectrum analyzer use.  Also,
with the SM-220, I have to manually toggle between
panadapter and transmit monitor functions (I use it
strictly for transmit monitoring).

The SB-620 also can be used with just about any IF
without internal modification.  The input amplifier
can be switched to operate as a mixer, and then you
only need a source of LO signal to make it see the IF
signal you're feeding it.  In my case, to make the
SB-620 (set up for 3.395 MHz) see 8.83 MHz, I used 
a crystal for 146.76 MHz from an old 2m rig.  12.23 -
8.83 = 3.40... the sweep oscillator in the '620 needed
only a slight tweak to put the 'Pip Center' pot in the
middle of its range.

73,
Bryan WA7PRC

Leo Fahmie wrote:

> Yo Bryan,
> 
> The Kenwood SM-220 will NOT work with the TS-850S
> but the SM-230 will.
> 
> Bryan is incorrect.
> 
> 73,
> 
> Leo
> ----- Original Message ----- 
> From: Bryan Swadener
> To: <kenwood at mailman.qth.net>
> Sent: Saturday, February 28, 2009 12:55 PM
> Subject: Re: [Kenwood] SM-220 or 230
> 
> 
> > 
> > John Parker wrote:
> >> Does the 220 work with the TS-850S?
> >> 
> >> 73,
> >> 
> >> John KD7KFT
> > 
> > As it comes (without either the BS-5 or BS-8
> > panadapter modules), the SM220 will work with any
> HF
> > transmitter/transceiver.  Now, if you want to use
> it
> > additionally as a panadapter with your TS850S, you
> > will also need the BS-8 module (8830 KHz IF).  The
> > SM230 works with your TS850S without any extra
> > modules.
> > 
> > 73,
> > Bryan WA7PRC