[Elecraft] Sideband reversal

[George, W5YR]

As I recall, the original and still current practice of LSB on 40 and below
and USB on 20 and above was the operational mode of one of the very
earliest commercial SSB rigs, the Central Elecronics 10A and its subsequent
big brother the 20A. 

It used a WW2 surplus ARC-5 transmitter as a VFO in the 9 MHz range, and
the frequency coverage worked out such that on 40 and 80 LSB was generated,
while on 20 and up, it came out USB. 

Actually, even before the first commercial rigs came out, homebrew rigs had
been designed and written up in QST, etc. that used the same arrangement.
The advantage, of course, was multi-band coverage with a single VFO back in
the days when really good clean and stable VFO designs weren't all that
common or easy to build, especially when required to operate on more than
one frequency range.

I don't know when Swan brought out their first rigs, but they were merely
following the convention which by then had been cast in concrete.

Evidently the K2 follows "tradition" but, as you point out, they avoid the
reversed tuning that the pioneer rigs imposed.

72/73/oo, George W5YR - the Yellow Rose of Texas         
Fairview, TX 30 mi NE of Dallas in Collin county EM13qe   
Amateur Radio W5YR, in the 56th year and it just keeps getting better!
QRP-L 1373 NETXQRP 6 SOC 262 COG 8 FPQRP 404 TEN-X 11771
Icom IC-756PRO #02121  Kachina #91900556  IC-765 #02437

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"Ferguson, Kevin" wrote:
> 
> The Swan-350 (and possibly other swan rigs) reversed sidebands between upper
> and lower bands.  It was an analog rig, so there were backward scales on the
> dial for the reversed bands. In fact I think this is how the convention of
> using LSB below 20m, and USB for 20m and up got started.  At least the K2
> straightens out the tuning in software, so that clockwise movement of the
> knob always increases the tuned frequency (though it may actually be either
> raising or decreasing BFO)