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Author Topic: What to stick to? SDR or analog radio?  (Read 1074 times)

Offline Telegrapher

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What to stick to? SDR or analog radio?
« on: January 15, 2019, 1007 UTC »
Hello all,

I currently have an old RTL-SDR device and some analog tube radio's as well. My question is what should be the best choice for lifetime SWL'ing?
I know that my SDR has a lot of noise interference because it needs a PC to run. I have spend like 4 months to try using my Raspberry PI 3 for operating it but it leaves me without success (Lack of Linux knowledge). The old radio's have absolutely sero noise interference even on the lower bands (200KHz - 500KHz). I was thinking about this for a while, shall I buy a better SDR device like Hackrf or Kiwi-SDR? Or shall I keep using the old militairy tube radio's? The best things about my experience with SDR is the waterfall, the frequency digits. and the easy filters all in one little device I can carry in my pocket for easy outdoor DX'ing in places like forests, mountain tops, etc.

The analog radio's don't have a exact correct tuning scale, which the SDR does have. And all is done by carefully listening instead of monitoring the waterfall spectrum. Also they are bulky, heavy, and usually stored in museums (that's the place where I bought some for SWL'ing at my home shack).

The only good part about my experience with analog radio's from the early days is that they are easy to repair. The radio's nowadays are hard to repair, parts are getting smaller in size etc. While a tube is easy to replace.

About the tube radio's, There will be one day that there are no more parts available for replacement as most isn't produced anymore. These days I can only buy transistors in the local electronic shops around me. So that also leaves me thinking about their historical value and whether or not I should use them till they become even more damaged and eventually break and die..

I know that the older radio's last much longer than the new stuff nowadays. The oldest one is about 73 years old and it's still alive and works like new.. Even after it's journey inside a bomber plane from the USSR and been recovered after WWII from the disassembling process of the airplane's wreck.

If anyone has experience in both kind of radio's, I would love to hear more about it. Things like how to take care of the older devices especially.

Kind regards,
Telegrapher.

Offline ChrisSmolinski

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Re: What to stick to? SDR or analog radio?
« Reply #1 on: January 15, 2019, 1110 UTC »
With some care, you can reduce RFI levels from computers to an acceptable level. I have four on in the shack at most times, for example.

As you noted, SDRs have have substantial advantages over analog radios. You can see the entire spectrum at once. Generally better frequency accuracy. You can record chunks of the spectrum for later analysis.

The advantage of an analog tube radio over an SDR... well I guess it keeps you warm in the winter  ;D

If your current SDR experience is with an RTL dongle, you'll likely be pleasantly surprised upon trying something else. In addition to being able to share it online for others to use, one advantage of the KiwiSDR is that it can be easier to set up, if you don't have much prior experience, since the interface is a web browser. In the same general price range, the AirSpyHF+ and AFEDRI SDRs are also good choices.
Chris Smolinski
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Offline Josh

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Re: What to stick to? SDR or analog radio?
« Reply #2 on: January 15, 2019, 2026 UTC »
As for sdr, I've a RSP2 and RTL V3 here, as well as a Icom Pro2. The p2 allows for some of the functionality of an sdr minus the need for a noisemaking pc, it has a fft display out to 200KHz and dsp filtering and de/modulation. I can use the p2 for decoding digital sigs with a pc but it doesn't have an iq stream to feed a decoder app with, some decoders are designed to work best with an iq stream rather than an audio feed. I use the p2 to do voice intercept as well as HAM digital modes, and use the sdrs to do decoding work in the utility bands. Also, I've had ten or more vrx up and running with both the RSP and RTL sdrs. I can have two receivers up with the p2 as it has dual watch. To have the same 10 receivers up with the analog rigs I'd need to have 10 analog rigs. It's fun to compare the size of the RTL to the R390A and tell people there's 10 or more of these R390As inside this tiny silver dongle. When the 390A was in use by US int agencies and mil, there'd be entire buildings filled with these things feeding tape recorders or headphones attached to some poor dittybops, sdr changed all of that, save for the morse intercept operators. I know a guy who was stationed in Turkey listening to Russian and Chinese mil cw circuits via the R390A, a lot of history in these rigs and fun to operate. There seems to me much more of an experience operating the analog rigs than the "dry and sterile" sdr, but the sdr has its place assured by the future.

Also on hand are two R390As and a R388, and these are nice for am listening on any freq. I find the audio much more pleasant on the 390As than even the sdrs running the synch am mode. The 390As are also very good at cw and rtty, but I mostly use them for ambc and swbc.

Moral of the story; it's nice to have both on hand.
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