The great-grandfather of SDRs?

[kc2asb]

While reading through back issues Popular Communications, I came across a review for the Dymek DR-333 computer-controlled HF receiver in a 1990/91 issue.

All receiver functions were controlled through a PC, and it even boasted a spectrum analyzer. At $1,500, it was nearly the cost of two high-end table top receivers. Definitely ahead of its time, though. Did anyone here own one of these?

McKay Dymek DR333 DR300 DR360 shortwave receiver

The McKay Dymek DR333 is a single board, computer controlled shortwave receiver. This dual conversion radios tunes from 10 kHz to 29.99995 kHz in AM, SSB, CW, RTTY and FAX modes. The DR-333 comes with a 6 kHz ceramic filter and 2.7 kHz mechanical filter. As many as 9999 memories and 999 band-scans are supported. A spectrum analyzer function with up to 400 stops is featured. Passband tuning is available. Outputs include: 600 Ohm Line, Speaker and earphone. The serial RS-232 jack is a DB9. It requires 12 DC at 320 ma. It requires a PC with DOS 3.1 or higher, with 256K RAMS and one 360K floppy drive. Software supplied on 5 inch diskette. 7.375 x 2.25 x 4.75 inches 2 Lbs.

 

[BinaryMode]

I always thought the Icom IC-PCR1000 was one of the first SDRs. Now I wonder if it was really an SDR or not? Much like the OS535 board for the Pro-2042.

Impressive that shortwave radio goes down to 10 kHz.

 

[kc2asb]

I always thought the Icom IC-PCR1000 was one of the first SDRs. Now I wonder if it was really an SDR or not? Much like the OS535 board for the Pro-2042.

Impressive that shortwave radio goes down to 10 kHz.

The Dymek would still be a good performer today. According to Rig Pix, the PCR1000 is a computer-controlled receiver like the Dymek. The detector, filters, etc are still analog hardware whereas on an SDR they are usually implemented through software, if I understand correctly.

 

[KC1UA]

The Icom black boxes were nice devices and still are to this day. Ten-Tec had a gem as well in the RX-320, and a more robust version which as I recall was the RX-321 maybe. I owned both. At the time they had some of the best audio output there was. All of those oldies paved the way for where we are today, but the real SDR revolution started when (can't think of his name) discovered that those cheap DVB-TV dongles could receive across the RF radio spectrum. Thinks kinda flew from there, but this is fun to talk about the oldies. One real true early SDR was the RFSpace SDR14. I used one with the IF out of an AOR AR5000 for spectrum display. That has to be at least 20 years ago now.

 

[merlin]

Early Win-Radio was a computer controlled receiver, and I think they had atransceiver version.

 

[BinaryMode]

Ah, yes Win Radio. I remember those adverts.

 

[prcguy]

I don't think the DR333 is an actual SDR and probably just a computer controlled conventional receiver with no hardware functions like IF BW or demodulation being handled by computer simulation. Its advertising claims a dual conversion superheterodyne with no mention of any DSP or SDR functions, although the term "SDR" had not been publicly mentioned in 1992. Around 1994 I worked on one of the first actual SDR radios made by Hughes Aircraft which we called the Hughes Digital Transceiver or HDT.

 

[kc2asb]

I don't think the DR333 is an actual SDR and probably just a computer controlled conventional receiver with no hardware functions like IF BW or demodulation being handled by computer simulation.

I agree, it does not meet the definition of an SDR, but it is definitely one of the earlier computer-controlled receivers available to hobbyists.

 

[ka3jjz]

Quite right. I think many who owned the RX320 (including me) series would concur that in the world of computer controller radios, this one (and the RX321) are the kings. The PCR series suffered from very poor ultimate selectivity and resistance to overloading. Even Passport to World Band Radio rated the RX320s very highly. Interesting fact - the 320s were built by TenTec engineers with express purpose of introducing people to the hobby. It was never intended to be a serious radio - but they hid many features that serious DXers would want - including up to 24 different bandwidths (depending on which application you used). It was a fantastic computer controller radio for its day

 

[kc2asb]

Passport to Worldband Radio did excellent,in depth reviews. I have some old ones from that time kicking around. I'd like to see the reviews of the TenTecs and the Dymek. Pop Comm reviewed the Dymek, but their reviews often just scratched the surface.