Here is more info on the the performance of the W2A after the mod.
Well folks I have had my IC-W2A for one week now & am,needless to say
suitably impressed. But now my comments...
Why did Icom have to change the DC input socket to what the W2A has.
It is very unusual & as far as I can find out, Icom are the only people who
can supply a plug for it. I think they should have stayed with the more common
2.1mm DC jack as per the IC-32AT.
I did some checks of the receivers using an IFR 500A signal generator
& the following is what signal level I needed to get 1 "S" point on the W2A's
S meters.
70MHz, 1mV (milli-volts)
80MHz 0.5mV
90MHz 0.25mV
100MHz 75µV (micro-volts)
110MHz 1.5µV
From here to 170MHz less than 0.2µV
173MHz 1.5µV
174MHz 75µV
200MHz 75µV
250MHz 0.5mV (whats going on here???)
275MHz 4µV
300MHz 1.5µV
320MHz 5µV (changed to UHF main VFO from here on)
400 - 450MHz less than 0.35µV
460MHz 0.75µV
465 - 510MHz less than 1µV
520 - 690MHz less than 2µV
700 - 999MHz varies from 7.5µV to 2µV, dips to 0.35µV at 900MHz.
Quite impressive, but I would really like to get better sensitivity
at the 70 - 80mhz end. Studying the circuit diagram shows bandpass/bandstop
filters all over the show, so maybe its possible to modify a few to increase
sensitivity here.
I am gathering together the ciruits of the Icom IC-R1, IC-24AT &
W2A to compare the front ends so we will see what comes of this experiment
in the near future.
One other worry was the on/off switch, how do you turn the set off
when the battery is flat. I am concerned about running the battery to zero
volts, hopefully this does not occur. I have been disconnecting the battery
when charging to prevent anything funny happening.
The antenna supplied with my W2A is an FA-1443BB, whats the difference
between this & the FA-1443B, & the FA-4B supplied with an IC-R1.
One more gripe, I dont like the plastic plug/covers over the DC jack,
headphone, external speaker sockets, they should have been rubber as per the
IC-32AT, as I can see already that they will not last very long after prolonged
use. Boy what a moaner, you say, small complaints but this would really have
made it the best. I wonder what Yaesu & Kenwood are going to do to compete
with this?
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