A slightly-modified TS-830 is almost impossible to beat in the "bang for
the buck" department, especially on CW. With the International aftermarket
filters, together with a little improved interstage shielding, it a
fantastic performer in a small box. The 800 Hz CW offset is a nuisance, but
it can be easily dealt with.
N4KG Sez:
>Fortunately, there is a simple solution to this dilema.
>
>The CW offset is determined by a small inductor in the VFO module.
>Replace this inductor with a 2.2 uH choke and you will have a 400 Hz
>offset without resorting to RIT/XIT adjustment. To access this coil,
>remove the 4 screws around the VFO and carefully pull the VFO unit
>out from the radio. Disconnect the cables from the back and remove
>the cover. There is a small solenoid wound coil visible on the board.
>This is the CW offset inductor. I believe it's value is around 1 uH.
>If you cannot find a 2.2 uH choke, you can add a few turns to the
>existing part or wind your own choke. The difference between the
>RX and TX frequency displays will tell you the offset.
Actually, there's an even easier way to do this that doesn't require you to
fool with the VFO. Just wire an additional pot into the carrier oscillator
VCXO control voltage line and adjust it to create the desired offset with
the RIT set to zero. Switch the new control voltage in out on CW by using a
small 12V relay run by the +9 CW TX control line already in the radio. (I
think it's called something like that; I'm working from memory without my
schematics in front of me.) I used a small Radio Shack "sugar cube" relay
with a 12V coil to do the switching; it works fine with 9 volts on the
coil. If you're interested in the details, e-mail me (NOT the reflector!)
and I'll arrange to get you a copy of my drawings for various mods to the 830.
-----------------------------------------------------------------------------
73...
Randy Farmer, W8FN
W8FN@erinet.com
W8FN@compuserve.com
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