You have a point, Joe; both transmitters and receivers fall into
different classes of performance depending on the price range. But there
is still no valid reason for any transceiver to perform significantly
worse than the comparable "best in class".
Stepping up to a completely different performance class does indeed cost
money; but improving performance to equal the "best in class" is much
more often about attention to detail.
Because there has been such a market-driven obsession with "receiver
numbers" like IP3, the best designers in the development team are
working on the receivers, while the design of the transmitter is
apparently being left to the tea boy. There is a real lack of managerial
- and indeed, moral - imperative to design the best possible transmitter
that can be produced within the given budget.
Another aspect of the "$900 rig problem" is that most of these
transceivers were originally designed for the domestic market in Japan,
which is much more heavily biased towards mobile operation due to the
population density. Many aspects of performance are sacrificed for the
sake of compactness as well as low cost; but in addition to that, they
are specifically designed for operation with relatively inefficient
mobile antennas. That means the receiver needs to be quite sensitive and
the transmitted IMD will be 6-10dB further into the noise. But when the
same radio is used at a fixed station with even a simple wire antenna,
the receiver becomes overly sensitive and has poor strong-signal
handling, while the transmitted IMD looks very poor indeed.
Some years ago, the Japanese manufacturers were quite surprised that
what they thought of as "mobile" transceivers were being marketed in the
West for fixed-station use; but now these $900 rigs have become a major
part of the Western market. Beginners reasonably ask why they should pay
more... and I don't think that anyone is telling them.
73 from Ian GM3SEK
>-----Original Message-----
>From: Joe Subich, W4TV [mailto:lists@subich.com]
>Sent: 04 May 2013 15:36
>To: Colin Lamb
>Cc: Ian White; amps@contesting.com
>Subject: Re: [Amps] Pre-Distortion Linearizer
>
>
>On 5/4/2013 9:37 AM, Colin Lamb wrote:
>> The breakthrough may be when one manufacturer begins marketing their
>> low end transceiver with a -35 db IMD rather than a -25 db one. That
>> would give a distinct marketing advantage.
>
>The problem is that manufacturers are not going to be able to produce a
>"low end transceiver" - at least at the low end price point - that has
all the
>features demanded by the marketplace. The technology simply does not
>exist to make a broadband (no tune), 100W output amplifier that runs on
>11V (low end of a battery life) and achieve -35 dB in the final and do
it for
>even 10% more than the current crop of $900 rigs.
>Add other requirements like reasonably clean phase noise performance,
>acceptable (~80 dB) 2 KHz receive IMD, and acceptable ~100 dB) blocking
>dynamic range and it is simply not possible from a cost perspective.
>
>$900 rigs are there for a reason ... that's all that many amateurs will
pay.
>
>73,
>
> ... Joe, W4TV
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