Roger: While many of the technical points are valid, using Consumer Price
Index (CPI) to compare "rig" prices is not realistic. Electronics,
particularly consumer electronics is the outlier -- it does NOT follow the
CPI..For example, a typical TV now is a 42", which goes for $450 in 2015. A
21" RCA color tabletop TV would cost $500 in 1960. Using the CPI, that
would be almost $4000 in today's dollars, BUT, a $450 42" TV (Typical,
today) would cost $56 in 1960 dollars. Its just not fair to use CPI to
compare then and now electronics prices. Too much has changed. I used TVs.
It becomes even more absurd when comparing digital computers!. --Mike,
WV2ZOW
On Fri, May 22, 2015 at 1:28 PM, Ken K6MR <k6mr@outlook.com> wrote:
>
>
>
>
>
> On 5/22/2015 8:58 AM, Kevin Stover wrote:
> There are NO 12V final amateur transceivers that make -40dB IM3, none.
> Never have been, never will be. The best are at -33 to -35.
>
> As Paul said, it can be done. Manufacturers tout receiver figures that
> are nonsensical. They are real, they can be duplicated and proven, but
> the gain us little to nothing as long as the bands are loaded with -30db
> transmitters and worse when they are mis configured, or mistuned. From
> what I've read, the 4CX1000, 4CX1500 and the Chinese FU728F should be
> capable of better than -40db with a number of the larger tubes like the
> 4CX3000 (designed for low IM) and other commercial Tetrodes capable of
> even better numbers particularly when run at amateur power levels .
> Some of the big Triodes are truly impressive. So is their filament power!
>
> As has already been noted, IM-3 is even more important for hams on the
> crowded bands. As for the filters, they wouldn't need to be so robust
> if the SS finals were not run so hard. Double the number of devices and
> the move away from compression would already be noticeable.
>
> That brings two problems with it. Many hams would still push it into
> compression to use the new found 3 db while the FCC would balk because
> of that reason. That's why the 4CX-3000 amps are not available. Of
> course a $1,600 socket dampens the desire for many
>
> Someone got the rig and manufacturers mixed up. The 990 is a Kenwood and
> the Yaesu is the FT5000MP with I believe a bit better IM than the
> Kenwood. The Yaesu can be run class A, for even better numbers. I run
> mine Class A to drive a Tetrode for better than -40db. True, the
> FT5000MP is big and heave with a built in AC power Supply and no ability
> to run off 12 VDC. I believe they run 50 V on the finals.
>
> Although it costs to add adaptive predistortion, or the fixed
> distortion once it becomes commonplace with the development of dedicated
> ICs the prices should come down. I doubt it'd run more than 100 or 200
> dollars to add to a rig, if that. The problem is not anything the
> purchaser could see, or hear unless it might be compliments.
> The knowledge, technology and readily available parts are here and all
> those useless features on the receivers sound great, but you can't clean
> up the other guy's signal. Until the signals are cleaned up these fancy
> receivers gain us little.
>
> Instead of adaptive distortion these rigs have added features that let
> hams do all sorts of things to the signal except make it cleaner. Today
> there is a set of steps to set up a transmitter for ALC, compression,
> and gain. Don't follow the steps and that nice sounding signal turns to
> garbage.
>
> IF and I emphasize the IF ALL new transmitters had an IM3 of -40db or
> greater, how long would it be, before these fancy receivers would start
> to earn their keep? 1 or 2 years, or several decades?
>
> A few years back a new ham was complaining about the poor receiver in
> his new, top of the line transceiver. Not one person in the group could
> convince him that it was the other station's fault. He was so wide his
> signal was in the pass bad of the new ham's receiver. He looked at the
> specs and still did not, could not, understand why he still heard the
> other station.
>
> We balk at spending a little extra to clean up the bands, because it's
> the other guy who benefits from our purchase. Now if he could hear the
> improvement if the other guy purchased the clean rig... However, back in
> the 60s a Collins station (with a clean signal)could easily run 3 or 4
> thousand dollars. A good TV set ran as much as $4,000 and reliability
> was poor at best with tube changes common place. BTW $4000 in 65 is
> $39,798.44 today. That's just shy of $40,000. I purchased a new
> Bonneville Convertible for $3,600 that weighed just shy of 6,000#
>
> Few people would consider a $40,000 rig today. With accessories,
> amplifier, tuner, tower and antenna that would push the station close to
> $75,000. And we grouse about $5,000 to $8,000, but fear not. Icom now
> has a $15,000 transceiver on the market. Just think of the difference
> in features and what that rig would have cost back then
>
> The band will not get better until the signals get clean.
>
> 73
>
> Roger (K8RI)
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