If you are not interested in the IC-7800, please delete this message. If
you may get a little queasy listening to a little criticism, or if your
blood pressure may go up, please delete this message also.
I just saw the Icom 7800 review for the first time.
Without ragging on the reviewers, because I'm sure they are all good
guys, this review tells me very, very little about the electronic
performance of the radio. It is disappointing.
For example, two full paragraphs are devoted to the 'virtual D'Arsonval
moving coil meters', but nothing is said of its CW performance, save for
two short sentences involving the phrases 'CW operation was a breeze'
and 'the dynamic range paid off'. What in the world does that mean?
I gleaned much more information from the pictures and the numbers.
I can tell you one thing: Just by looking at the CW keying waveform, it
can be predicted that this radio will have key clicks and thus occupy
excessive bandwidth in CW mode. The sharp transitions at both the
leading and trailing edges are a bit worse than we've seen recently in
ARRL's product reviews. Those corners aren't rounded at all!
It would be unfair to compare this transceiver to, say, an FT-100 by
saying that the FT-100 is better because it covers more VHF and UHF
bands. The 7800 isn't meant to be that kind of a rig, right? In the same
vein, this CW keying waveform leads me to wonder if the 7800 isn't
really meant to operate CW seriously.
I don't get the following apparent contradiction. In the fourth
paragraph, we read, "ICOM has set a new standard in the important
dynamic range area." But in the 'Receivers' section, we read, "The
two-tone third-order IMD... was measured at 98 dB at 14.1 MHz with 20
kHz spacing and a respectable but not quite the best we've seen of 89 dB
at 5 kHz spacing." Gee, I wonder which receiver was the best? We'd
better pay close attention to it, whichever one it is!
Earlier, we read, "The important third-order intercept... came out
better than we have seen at +37 dBm, close to ICOM's advertised 40 dBm
(10 W!)." But since when do we get excited over coming *close to* the
spec? Have you ever heard, "The new Ten Tec was impressive, coming
really, really close to the factory spec!"? Oh, please.
Well, at least those meters are impressive. We get not one, not two, not
three, not four, not five, not six, but SEVEN screen shots of those
magnificent meters!
As for the phase noise, okay, I suppose it looks fine. But the record
held by the $95.00 Ten Tec 1340 (September 1998) still stands,
apparently.
Transmitter IMD is very average.
Is it quadruple conversion? What is the filtering scheme? What does the
front end look like? The power supply? Birdies? etc., etc.
Biggest question in my mind: Exactly what "new level of performance" has
ICOM achieved?
"Yes, I know you've just spent $11,000 on your radio, sir, but you're
still going to need to buy a microphone."
And, sorry, but if I see Joe Walsh's goofy mug one more time in QST, I
think I'm going to puke.
Al W6LX
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