Talbot Andrew wrote:
I'm sure this was all explained last year when the mode was being developed
but can't find any reference to it now. And the Tech Notes that come with
V0.94 don't cover this aspect.
From the TechNote :
The frequency deltas can assume one of 16 different values. After sending one
tone,
the next one is shifted by the appropriate amount, up or down depending on the
setting of the USB/LSB switch. With 16 deltas we need 17 slots, and any overflow
causes a wraparound.
Maybe I haven't been much clear there. What I meant is that the direction of
the frequency
shift depends on the setting of the USB / LSB switch in the Option menu of the
program. If the amount of the shift is such that we go over the highest (or the
lowest)
slot, then a wraparound occurs, and we re-enter from the opposite side.
In its first incarnation Jason was sideband-insensitive, but it had a greater
band occupancy.
I asked for opinions, and the general consensus was that the need to specify
the USB / LSB
mode was a small price to pay for a reduction in bandwidth.
A thought has just occurred while writing this - does the direction of
frequency shift matter, which can then be taken modulo 16, giving 16
possible shifts from 17 tones? Which means the sideband in use is
sensitive. Have I answered my own question ?
Yes, you did.
73 Alberto I2PHD
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