[Elecraft] K1 # 690 receiver: more good news

[Ron D' Eau Claire]

Bill wrote:
> I thought that most rigs in the 60's and 70's were typically dual
> conversion, with the first mixer stage controlled by an HFO (usually
> crystal controlled) to a wide IF (usually 200-500 kHz wide), and then an
> LMO to a narrow IF (where the crystal filter was), then a product
> detector to audio. This is the basis for the Collins, Heath, and Drake
> units, I'm pretty sure. (Although the Drake was probably triple
> conversion, getting the narrow filtering from a low frequency IF)

Yes, the manufactured rigs continued to sell multiple conversion designs for
years.

I'm talking about the REAL state-of-the art stuff being built by hams that
clearly out-performed the commercial gear. See Hayward/DeMaw's "Solid State
Design for the Radio Amateur" for examples, as well as many QST and Ham
Radio Magazine articles in the 50's and 60's. Many of them were pre-solid
state showing single conversion state-of-the-art designs using
beam-deflection mixers and other high dynamic range innovations. The
technology changed so fast that many of these innovations never made it into
manufactured rigs.

The manufacturers are always a bit slow, since they want to recover the
costs of their engineering efforts, and it takes time to create a brand new
design anyway. Also, smart businesses keep selling the old technology as
long as there are takers, carefully timing the introduction of new
technologies to balance losing market share with killing off high-profit
sales on older designs. All of the economic forces tend to encourage holding
onto the older designs as long as possible.

You bring up an interesting point about the evolution of our hobby, Bill. In
the 50's and 60's - indeed into the 80's at least, the true "state of the
art" involving the latest innovations that one would find on the air were in
the non-commercial rigs on the ham bands. The manufacturers like Collins,
Johnson, National, Hallicrafters and the others had a reputation for giving
you solid, stable and dependable equipment, but it was definitely not the
latest technology as you point out. In this case, the multiple conversion
designs held out for many years in spite of their clearly-identified
shortcomings.

That begs a question. Are we now sitting back and waiting for the
manufacturer's to 'catch up' nowadays, ignoring the latest state-of-the art
until they provide it to us in a turn-key box?

I don't know. Perhaps it is simply that there are fewer hams interested in
design work or perhaps the complexity of the technology of today is beyond
home workshops. But there are still leaders out there who keep stuffing the
pages of publications like QEX.

Ron AC7AC
K2 # 1289