> Welcome to the Ten Tec group Ed. I appreciate the time you have
> taken to help us understand the effort the League goes to to
> get solid performance data on our gear. I knew it was a daunting task
> but had no idea how much so. Thank you!
Well, I do own a Ten Tec and like it, so I belong here. :-)
Glad to offer any info I can on the ARRL Lab! I do know it pretty well. :-)
Yes, the
testing is rather extensive. It was also a daunting task to do that much
writing in a couple
of hours. That was as many words at the typical QST article. :-)
> On 6 Mar 2003 at 17:47, Hare,Ed, W1RFI wrote:
> > But I remember one year I was mobile with my Ten Tec Omni D during
> >the ARRL Phone Sweepstakes. I parked right under the W1AW
> >antenna array and was able to work 'em on phone while they were
> >blasting away on CW, at least on 20 meters. That rig is still my
> > main rig at home, btw. :-)
> In some ways I think the design of our gear may be going backward.
> Take Ed's comment about his Omni D for example. The Omni has a
> double tuned narrowband RF amplifier using real inductors and real
> capacitors. The arrangement uses rack driven slug tuned coils and
> fixed value capacitors, ala Collins and Drake. The balance
> of the front end is pretty conventional with a bouble balanced diode ring
> mixer and a strong post mixer amplifier, then on to the noise blanker
> gate and the IF filtering. One can peak the desired signal and reject
> lots of other RF energy WITHIN THE BAND being worked. So......only a
> limited
> amount of interfering signal power ever reaches the mixer. Relatively
> speaking, the mixer and following stages have a pretty easy task in
> staying linear because of the limited power being applied.
Now, in fairness, there were a number of factors involved. First, I was using
a mobile antenna. Those are somewhat lossy. The antenna was vertical, parked
under a horizontally polarized dipole. The rig has a preselector, which was
peaked on the desired part of the band. I believe I used the attenuator, too,
and, of course, the SSB stations were pretty strong themselves.
It did speak well for the Omni, though.
But how many hams want to do what I did? Few. Most hams who operate with
modest antennas find that their rigs do NOT overload from strong signals. In
that case, their receivers have adequate dynamic range and a receiver with
better dynamic range won't sound the tiniest bit better. That is why I say that
for most hams, the features and how they are implemented are probably more
important than raw equipment technical performance.
73,
Ed Hare, W1RFI
ARRL Lab
225 Main St
Newington, CT 06111
Tel: 860-594-0318
Internet: w1rfi@arrl.org
Web: http://www.arrl.org/tis
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