[1000mp] QST Product Reviews whitewash (long)

Mon, 15 Apr 2002 18:09:20 -0700

OK, I know I'll get decapitated as a result of putting this on the 
entire reflector. But I'm willing to take that chance in this case - 
- -

I just want to complement Tod on his thoughtful reply and comments.

(ByWay, Tod, everyone knows that your name should be spelled with two 'd's'!=
)

de/smitty/w6cs

>I have been reading the mail on these exchanges (as I expect many other are
>doing). I have no idea whether or not any Kenwood or ICOM representatives
>are 'reading the mail' on the FT1000MP reflector, but I certainly expect
>that someone from Yaseu has seen the comments.
>
>Ed, Joe, anyone --- Do you suppose that the marketing requirements for the
>transceiver products that are being discussed include something that states=
,
>"must be able to operate from 13.8 VDC" AND "must be capable of an RF outpu=
t
>into a 50 ohm load of at least 100 watts".  If that were the case, would
>that not strongly dictate to the designers that the solid state devices use=
d
>in the transmitter section final amplifier must be designed to operate from
>a 12-13.8 VDC voltage source. In turn, would that not make linear operation
>at high power very challenging to achieve? For contest and DX radios do we
>really care if they operate from 13.8 VDC (except using a high power
>inverter). Maybe changing that requirement would make the design task easie=
r
>and hold the line on cost. The real issue probably is tied to marketing
>volumes required or desired.
>
>As I recall, my TS-950SDX had finals that operated at 48 VDC or so which
>allowed them to achieve more linear output.
>
>Most of us recognize that technical design is filled with compromises. As
>several contributors have mentioned, they feel that  the weighting of
>certain things may be 'incorrect' -- at least as they see it. Of course the
>ultimate weighting of things is tied to 'will enough people buy it to
>justify production'? In those days when I was associated which such
>decisions it was always an agonizing choice between technical purity,
>manufacturing cost and sufficient product features to assure market volume.
>
>I suspect that if the designers were allowed to design radios that ONLY
>operated CW or ONLY operated SSB and did not have to operated from 13.8 VDC
>sources and did not have to include every band from 160 meters thru 6 meter=
s
>( or even 2 meters and 70 cm) the resulting products would (maybe) have
>better performance within their slice of amateur life. The cost might be
>unacceptable, however, because the production volumes for each segmented
>product might be insufficient.
>
>The above may or may not be the reason that many of the radios available to
>us today cannot perform at state of the art levels. If, however, we become
>more sensitive to the implications to the test results it is likely that
>more buyers will tend to select products which have good test
>characteristics. For that reason it seems important to clearly state things
>much in the fashion that Joe (K4IK) has suggested, "We would expect to see
>third order IMD results at least -36 dB and fifth order products at
>least -46 dB." I think the follow on sentence might be softened to somethin=
g
>like the following: " ..in order to minimize the production of rf energy
>which will reduce the ability of others to use close by frequencies". Other=
s
>may have a better choice for the words. The point is that we need some
>institutional entity to be capable of the measurements and also capable of
>helping amateurs understand the significance of the values measured. It
>follows that that same institution needs to thoughtfully establish a
>'targets' that represent acceptable, good and excellent design and
>manufacturing performance which are accepted by amateurs and are known earl=
y
>in the design cycle by manufacturers. I can see where a rating system of
>acceptable, good and excellent could help manufacturers make design
>decisions and also help amateurs select equipment while making their own
>economic and performance trade-off decisions.
>
>There really is only one national organization that has the resources and
>the stature to do this -- ARRL. If we think this is an important thing for
>the national organization to do (and that means it probably will have to NO=
T
>DO something else), then we should be discussing these ideas with our
>Division Directors. They will need to adjust the League policies to change
>priorities for the ARRL Staff.
>
>The number one priority for ARRL is to do those things which assure that
>amateur radio has frequencies on which to operate. Almost every action and
>program undertaken by the League is in some way in support of that priority=
=2E
>None of us would have it any other way! Still, some part of the League
>resource pool plausibly should be (and is) spent is support of proper
>operation on our bands. An extension of that thought would be 'proper
>operation using "acceptable" equipment.
>
>Tod Olson, K=D8TO
>
>
>
>
>
>
>
>
>
>-----Original Message-----
>From: [email protected]
>[mailto:[email protected]]On Behalf Of Joe Subich, K4IK
>Sent: Monday, April 15, 2002 1:00 PM
>To: [email protected]
>Subject: RE: [1000mp] QST Product Reviews whitewash
>
>
>
>Ed,
>
>It would be refreshing to see: "the transmit IMD of this product is
>simply not acceptable for a modern radio.  We would expect to see
>third order IMD results at least -36 dB and fifth order products
>at least -46 dB.  Any manufacturer that releases a product which
>fails to achieve that standard simply does not care about the
>amateur market!"
>
>It is time to call them as they are and clearly condemn sloppy
>designs.  If those who have the ability to accurately measure
>performance in their reviews would do so, we might see more
>attention to quality.
>
>73,
>
>    ... Joe, K4IK
>
>
>
>>  -----Original Message-----
>>  From: [email protected]
>>  [mailto:[email protected]]On Behalf Of Hare,Ed, W1RFI
>>  Sent: Monday, April 15, 2002 1:10 PM
>>  To: '[email protected]'
>>  Subject: RE: [1000mp] QST Product Reviews whitewash
>>
>>
>>  The Review said:
>>
>>  "Unfortunately, one number we'd like to have seen change greately
>>  in the IC-746PRO did not -- two-tone, third-order transmit IMD.
>>  This number indicates whether the unit will generate undesireable
>>  intermodulation products that can lead to splatter. On the worst-
>>  case band -- 10 meters in both cases -- third-order products were
>>  down by about 23 dB in the original '746 and about 25 dB in the
>>  'PRO. In contrast, the IC-756PROIII's worst-case third-order
>>  products were down 30 dB -- not terrific, but getting there.
>>  The third order numbers were about the same on the worst-case
>>  VHF band, 2 meters.
>>
>>
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