I think we must accept now that on the HF bands especially 20 meters,
we have the highest desity of useage and signal levels compared to any
other commercial users. Hence i think it is time for us to improve our
own act.. That is to improve the transmitter 3rd order figures,
secondly the receivers 3rd order intercept points.. When we look at
all the commercial specs for trasmitter 3rd order IMD, and receiver 3rd
intercept points, i think its too low for heavily populated amateur
band use. Especially here in Europe. We say the commercial standard is
-31 below pep,, but no commercial user has to face 20 meters in the
morning in Europe,, hence this figure should be -40db below pep 3rd
order.
We as amateurs constantly ask on these refelectors whats good and bad
in commercial products,, antennas coax switches and amplifiers. But we
fail to ask these pertinent questions about transmitter and receiver
performance. We all boast about our new FT 1000d/mp,, but as indicated
the receiver performance is less than acceptable.. Likewise the people
at Kachina boast about how they saving money by doing away with the
front panel,, yet they cant produce a receiver with a 3rd order
intercept point of +30dbm.. When commercial receivers using old
technology were doing this in the seventies.. AOR now with their 7030+
has produced a benchmark receiver,, +30dbm third order interecept at
close spacing..yet at the current rate of transceiver performance
increase it will be in 20 years time that will get a high performance
receiver in a amateur transcievers. What will a Rhode&Swchartz be
then,, probably +90dbm. My TS450s when modified as per Dr Rhode is
better than my Ft1000, but i could not convince any FT 1000mp owner
that my 1000 dollar radio is better in the receiver than the 4000
dollar radio.. Oh well.. Like wise take the latest generation of
radios,, all the cut down models receivers are identical in specs,,
TS570s, TS950sdx,, IC775/ic756 etc there is little separating them in
real performance terms. They wonder why old hams dont want to buy new
radios,, when in reality you might as well use your old Drake or
Hallicrafters on receive,, So amateurs radio should be asking the hard
questions of amateur radio manufacturers, and not accept these poor old
technology designs.. Dr Rhode has pointed this out very well,, how
simple changes could result in this huge performance increase.. The IC
765 with mods +30dbm third order intercept point,, kills the Ft1000
series by a long way.. Why buy a noisy front end FT 1000 mp,,, But the
average ham is not interested in this, because buying radios is about a
huge ego not about performance.
Anyway i will try not to be part of a money making con that delivers
very little,, i will buy PIN diodes and modify for the results that i
want. Like wise i will buy great products like Racal and the AOR 7030,,
the likes of Kachina Yaesu Icom and Kenwood can wait for my money till
they deliver a decent receiver.. I will say this,, buy a AOR 7030plus
and any el cheapo radio like the 756, or ts570s,, you will cover
yourself,, because you can be sure that the Ft 3000 or TS 999sdx will
not have a good receiver. Your AOR will be a good investment.
Igor
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