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RE: Icom 706



> Ok, here's a thought.  My principal reason for wanting the 
> smaller rig is
> for travel.  That said, it's looking like I will go with the 
> 706 for now.

OK, cool. :-)

> 
> Now...  With all the fuss about the full duplex issue...  I 
> own several 2M
> FM rigs.  My primary interest is in the AO27 bird and working the FM
> Repeator type birds.  I can do this effectively with the 
> 706's 70cm side
> (Which has a hell of a lot better tuning than my HT) and a 2M 
> Mobile rig.

This will work well, and in a mobile situation, the lack of full duplex
isn't as big an issue as it is with portable operation or when using SSB.

> Is *THIS* a solution that will keep me out of the Wolfhong 
> (SP?) hall of
> fame with you guys??
> 
> SInce my other interests are in HF, VHf Terrestrial, I think this is a
> good solution.
> 
> I may regret this.. But, Comments??

I may offer a little experience here, through operating on SO-35 and UO-14
(i.e. the 2 FM birds we get down here).  Personally, I find full duplex
serves two purposes.  Firstly, it's an instant check on one's signal
quality.  For you, this is really a minor issue.  Secondly, and related to
this is where you're able to adjust power or, especially antenna
orientatation, the ability to monitor your own signal allows you to adjust
for the link characteristics in real time.  Again, for a mobile, this isn't
as big an issue, as you can't easily pick up the car and wave the antenna
around (:-) ).  For portable operation, like I usually work, this ability is
the difference between success and failure, due to the smaller fade margins
you have when running limited power (in practice it makes the difference
between getting a good signal on a fraction of a watt and barely accessing
the bird on 5 watts when portable).

There are two other practical issues, again they won't stop you working the
birds, just means you're flying a little "blind", compared to the rest of
us.  Firstly, you won't know if you've been clobbered in a dogpile (or by an
alligator).  But that's a bit similar to being in the thick of a contest
pileup, except most others will know the outcome!).  Secondly, if the bird
is quiet, you may have no means of knowing if you can hear the downlink (as
they Tx noise when there is no signal on the input).  This is less of an
issue in the US, as you guys have much higher traffic levels.  Down here,
you may not know if you ever heard it during a late pass.  With full duplex,
you'll know as soon as you hit the button (and if you can't hear yourself,
will know not to Tx too much!).  Suffice to say, you feel 'blind' running
half duplex when you're used to full duplex. :-)

In short, I think the 706 will be fine for the FM birds, with a small amount
of compromise.  For SSB/CW operation, it would be extremely difficult, as
you won't be able to monitor your own Doppler shift (which you can guess to
"near enough" for FM :) ).

Anyway, that's my 2 cents worth. 
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