> subjective comments which might be a good thing. Has anyone taken a
> close look at the transmitt IMD charts and care to comment on it? It
Most important, keep in mind that is the ARRL's dB below PEP
measurement that makes everything look 6dB better than the
standard method.
On the negative side, Texas Star CB amplifiers (with class C
operation and no input or output filtering) measure about the same
3rd order IM performance at 100 watts PEP.
On the bright side, it is better than an old Central Electronics 10B
rig that uses a WWII command set for a VFO. We haven't totally
regressed on SSB IM performance.
> is really interesting that the 746, which is much less expensive than
> the 756, outperformed the the 756 in many areas plus has VHF
> capability. I have to wonder what the owners of 756 Pro's are thinking
5kHz test signal spacing might still be too wide, if one of the
signals falls on the slope of the roofing filter. Watch the swept
measurements carefully for real CW spacings.
> It still continues to amaze me how Icom can't make QSK work correctly!
> I suppose there are too few of us who make use of QSK but for me, it's
> a huge factor. Hopefully the Orion's QSK will have that "transparent"
> feel to it.
When I complained about my IC-706 QSK and keyer functions, and
later complained about the same thing in a 775DSP, a sales
manager told me they "never fix CW problems because no one
works CW anyway".
Perhaps he was telling the truth. Maybe you and I are the only
people left on CW Steve.
I'm more interested in how the transmitter behaves on QSK with
split frequency operation, and if it has problems like the 775DSP.
73, Tom W8JI
W8JI@contesting.com
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