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!