The above paragraphs appeared in a very good ham radio club magazine. I had some comments on it which I shared with the author and the editor. In light of our recent discussion of the ARRL Clean Signal Initiative, I thought that it would be useful for me to post these comments here.
I think the author misses an important point: The ability of radio amateurs to homebrew their equipment. I know from experience that it is difficult to homebrew traditional analog SSB equipment-- I am running analog SSB gear from two separatelocations. But here is the key: With traditional analog gear, homebrewing of the gear can be done. Not so with SDR gear.Sure, hams can do their own software (but usually this is limited to the software experts). I suppose that AI will let people vibe code their own SDR software, but I suspect that most hams will not do this. Even if they did, software development is a very different activity than is homebrewing of analog hardware.And as for the hardware, I suspect that we are rapidly approaching the point where this will come down to the placement of two (maybe one!) chips in their sockets. One ADC chip, one FPGA chip (programmed by an FPGA expert) and you are essentially done. Again, you are talking about a device that is radically different from a homebrew SSB analog transceiver. I can build an analog SSB transceiver, I really can't build an SDR transceiver.I have problems with your claims that SDR is inherently more sensitive than traditional analog rigs. Maybe if you go FT8, but not with SSB. As for selectivity, well some of my rigs have homebrew 10 pole crystal filters. The skirts are very nearly vertical.Finally, related to all of the above, is the commercial/SDR vs. homebrew/analog issue. If we go down this supposedly superior path, all of the rigs used by "amateur" radio operators will be commercially produced. They will be much like the Iphone in my pocket. And amateurs will have as much of an emotional connection to their "rigs" as I do to my Iphone: ZERO.The article portrays the users of analog gear as old Troglodytes, resistant to technological change. I just don't think this is accurate. Some of us stick to the older analog gear because it is possible to really understand it, and it is possible to really homebrew it. That, I think, is very valuable.73 Bill Hi7/N2CQR
I am hearing a lot (especially at club meetings) and reading in forums about repairability- or the lack thereof in the newer equipment. I won't cite specific models here, but several very popular ones keep coming up. Even the phrase "Beyond Economic Repair 'B.E.R." on pricey SDR rigs leaves them only worthwhile for spare parts, as I heard from several owners. This happens with different manufacturers.
ReplyDeleteIn emergency and non-optimal conditions, we may need to improvise and sometimes repair our equipment. You will have no internet for timing synchronization, might even suffer GPS outages, so certain digital modes (but not all) will display gibberish. The phrase "When All Else Fails ...Amateur Radio" will have no meaning. It's nice when it all works, I get that, but when it doesn't, Amateurs will have a problem providing public service during emergencies. At the point when the public needs us most, we as a group will be less relevant.
So as we are trying to squeeze out the last -dBc of sideband spectral mask or harmonics, think about the other parameters that may be of greater importance. With HF (and VHF) noise levels as high as they are, is it in any way a priority to have a transmitted spur that is -40dB below the antenna noise verses -30dB as measured at someone's receiver (even a local?), when they cannot hear the spur either way? Both are well under the noise. Surely, reducing spurious is technologically virtuous, even commendable.
But is this just a contest to see who has the best numbers?
Keep it Functional, My Friends, Keep it Functional! 73!
Though it would have been out of character, my response to the author of "Resistance to Change" would have been very short and, in fact, easily sent by CW: MYOB OM SK.
ReplyDeleteIf I wanted to reply to his last sentence, "These ops need to accept technological change and embrace new approaches to operating," my reply would also have been short: "No, we really don't." Full stop. End of discussion. No debate, no rationalizations, no partisan appeals, no sanctimony from either side.
Because I can't resist, I suppose I'd add that "need" and ham radio really don't belong in the same sentence. I don't "need" to embrace anything in particular because I don't even need ham radio. I pursue it for *my* purposes and not community ones. There *is* a community of those interested in the same things I am, but I really don't care how large it is or whether or not it plows new ground. I don't have to explain myself or to justify my choices and preferences. And I most certainly don't need validation and approbation from ops who really should MTOB (mind their own business).
There has always been room for everyone in the
ReplyDeleteham radio hobby, and this needs to continue, as
it should for any hobby that wants to survive.
I am guessing that the most popular segment
of ham radio might be those who primarily like to buy,
sell, trade, and collect ham radios, with many
of them getting on the air infrequently, if at all,
and certainly all this is perfectly fine.
But the essence of ham radio is incredibly
simple; it is listening to the radio and transmitting
on the radio. It only takes a $100 homebrew transceiver
to do both, which to many of us is far more fun and much less
expensive.
The author sounds more like a boss speaking to his employees
than a hobbyist.
--Walter KA4KXX
AI says that thermatrons were a part of the ARRL Handbook until the 80s with solid state being incorporated in the early-mid 60s. I am guessing we are talking at least 25 years and probably more because there are STILL applications where thermatrons make sense.
ReplyDeleteSDR was introduced in the Handbook around 2002. It hasn't quite been 25 years and the fundamental learnings of solid-state RF engineering are still relevant for a robust understanding of the science of radio.
There is a place for all of it.
I love the idea of a homebrew Frankenstein with all three. Pete is there with his Heathkit brews and suggestions of two DCRX's to make a SDR receiver. That really puts the "art" in homebrew radio art.
Our reality is analogue. We are analogue creatures. I use analogue, SDR and DSP hybrid radios. SDR is a numerical simulation of the apparatus between the antenna and the speaker. My daughter loves her grandfathers 50yrs old stereo that I got going for her. Full analogue audio from LP to brain. (Processed digital until cut into the master ?).
ReplyDeleteHam radio is big enough for all tastes and abilities.
Andrew: Yea, wouldn't that be nice! But when you start out (as the above author does, and some SDR entusiasts do) by proclaiming that anyone who is NOT using SDR is a "troglodyte", "stuck in rut" and "resistant to technological change" well, that makes happy co-existance a bit more difficult! 73 Bill Hi7/N2CQR
ReplyDeleteHey Bill!
ReplyDeleteThanks for posting this. The most worrisome part of this is the idea thwe might at headed towards only manufactured radios. That would be awful I think and I can totally see business people wanting to do it. Yikes! I really hope that doesn't happen.
I did analog electronics for my Masters degree and I work in digital electronics now. I agree with everything you said about analog construction. I think it's a lot of fun, and now that I finally have a 'scope at the house, I may even do more of it.
Having said that, I also think there's a lot that can be done with digital, but let me set out a single caveat.
1. Yeah, if someone wants to do store-bought digital, they oughtta do what they think is fun, but that's not what I'm talking about below.
I think that digital might not be any harder to really understand than analog. I've lost my phased-lock-loop and FM understandings, but I had them, and I remember them taking weeks of concerted effort to gain. I did filter problem after filter problem in my analog classes, and they weren't easy. Having gone back to physics grad school for a while, I found out they do the same pole and zero analysis we EEs do for filters for particle physics cross sections. Neither thing is particularly easy. I think there's a way to build really nice filters like you did, and it's fun, but the underlying math isn't easy.
I don't think it's conceptually more difficult to understand what's going on with I-Q radio signal analysis. Given, I haven't managed to keep it in my head any better than I have phased lock loops, but both are doable, I think.
Here's what I miss about ham radio books when I was a kid in Hobbs, NM. They were out of date. They showed kids building analog radios out of a few tubes, some transformers, a few air variable caps, a few lethal voltage terminals, and not much else :) That's what I thought ham radio was as I grew up. I could picture myself cobbling that sort of a thing together for not much money. I mean, heck, you could buy tubes at Western Auto.
I'm particularly enamored of the idea of Pico-W enabled CW and (probably) SSB rigs like the ones in the 101 Things videos for the exact same reason. The Pico-W costs about $7 and you can pretty easily get a stack of them. I know this because we have a Pico-W wifi front end on Project TouCans, our rock locked 20 m rig consisting of a Rockmite and a Tuna Topper. Doing just that, 15 year old KO6BTY and I have learned about inernet routing, WebSockets, and a number of other things.
But I digress. For not many parts, and not much money, a kid could think of putting together an amateur rig that would be pretty cool. I totally agree they could do this with analog as well. I think there's room for both.