Watch the presentation here: https://www.youtube.com/watch?v=MefojjQ84YYFarhan made it to FDIM 2026 (he must hold the "distance travelled" record!). We thought he might be talking about the latest version of the digital SDR sBITX, but NO! Farhan talked about the entirely analog LARCSet, a 30 dollar SSB/CW monobander. And in the process he shared a lot of good homebrew history and wisdom. I took notes on the video of his presentation:
-- Farhan recounts his discussion with Steve Hartley, President of GQRP. Farhan said he started to talk about SDR projects, but Steve steered him away from all that. Farhan said he realized that the homes of GQRP members are often small, and projects need to fit into took boxes that are pulled out as needed. There is often not even enough room to mount a screen. Analog rigs just fit better.
-- Farhan talked about the beauty of analog. He also shared some info on the recent timeline of analog rigs, going back to 1976 with the IARU gift kits made available by W1VD. Farhan very kindly mentioned the DC receiver that Dean and I are promoting. He talked about the 2003 BITX 20 rig, and the subsequent uBITX. Farhan talked about the cleanliness of all-analog rigs. "SDR's are a mess!" he said. "With SDRs it is difficult to avoid hash."
-- Farhan said he had trouble measuring the phase noise of the VFO in the LARCSet. He consulted with Wes W7ZOI. Wes told him this was NOT a measurement problem; VFOs have almost no phase noise. The level is even lower than that of crystal oscillators. Of course, crystal oscillators are more stable, but they also have more phase noise.
-- He noted that almost no recent homebrew design does not rely on an Si5351. This, he said, is "not a healthy situation." Indeed.
-- Farhan talked a bit about how Indian regulations seemingly require a deviation from the completly open source ethos. Indian regs require companies to have assets. So the PC board layouts have to remain proprietary.
-- Farhan talked about the sharpness and shape of the BP filter in the LARCSet. I remember talking to him about the shape of my BP filters in my dual banders -- I had to rebuild the filters.
-- On the crystal filters that form the heart of SSB rigs, Farhan noted that cheap low Q crystals often introduce a lot of loss in the filters (that may explain my problem with some styles of computer crystals).
-- A member of the FDIM audience asked about the Sharpie written frequency readout on the LARCset that Farhan showed to the group. Farhan told them that this was the only frequency readout used in the rig.
-- With the LARCSet, Farhan used varactors to vary the frequency. But the varactors he used were cheap but horrible. They varied the frequency as the rig hearted up. The LM386 was the source of heat. He also noted that the cheap varactors, while cheap, did not provide linear frequency readout. Farhan said the varactor scheme was still not perfect; he offered a PTO solution that could be used instead. Three cheers for the PTO!
-- Farhan said the LARCset was really an SSB rig, but when coming to FDIM he said he felt obligated to present a rig that included CW, "or they would throw me out of the room." Farhan described a scheme to generate CW based on what was done with the Atlas rigs.
-- Farhan said the LARCset might even work on 2 Meters. Hmmm.
-- On tuning, Farhan said he used a very large tuning dial (he said it was like a steering wheel) and then recommended the use of a smaller control that could serve as an SSB "clarifier."
-- Farhan pointed out that homebrew rigs are never really done; even decades later, they can still be modified.
Watch the presentation here: https://www.youtube.com/watch?v=MefojjQ84YY
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