Wow, we had a bumper crop of members bring in projects for this month’s Show N Tell session.
This is especially why attending the meetings pays huge dividends- to be able to see, touch, share, and converse about interesting projects. Here’s an abbreviated summary:
- Rotary Attenuator
(Note, I forget to take photos , but it, but here’s a similar version of what he brought)
John brought his Texscan rotary attenuator to demonstrate the size and function of an inline device very helpful for future fox hunt searches. The attenuator is needed to dampen the signal levels of the fox beacon, to avoid saturation of the hunter’s receiver front end.
- Balloon Beacon Designed by AB5SS
John brought his ready-to-fly PicoTrackerFW balloon payload beacon. It is a 7.5g 9mw payload with solar panels, planned for launch on Feb 18th in Batesville, Texas, south of Uvalde.
- VBand PCB project
(Note, I forget to take photos of his PCB, but here’s an earlier rendered pix of his outfitted board)
John is leading the effort to design and kit up a club DIY VBand interface between a CW key and a USB port, for VBand compatibility. The has recently received numerous interest to procure a club kit to allow users to learn/practice morse code via an internet chat channel (VBand). John has already received a PCB of the design and brought one to show.
- 24 GHz Transverter
With interest to participate in future microwave rover events, John brought a 24 GHz Transverter project that will output 2W. He shared that the North Texas Microwave Society (NTMS) in the DFW area was active in microwave operations and this unit might be an opportunity to participate as a roving event during the VHF/UHF/uWave contests.
As you can read in the club minutes, Jeff volunteered to offer his 3D printing capability for printing CW key options to primarily be used alongside the VBAND interface. His small straight key product was impressive. It was favorably reviewed as it was passed along the members. The responsiveness was very smooth and it looked solid, based on this design
Jeff’s larger key was based on this design
https://www.thingiverse.com/thing:630117 but he was still seeking our bearings and hw for a complete assembly.
Terry has been experimenting with antenna designs, baluns, and his latest is a folded 20m dipole. He brought the antenna stretched out across multiple tables at ~30′ and it included his DIY 500W balun. The folded dipole was constructed of ladderline/twinlead and it is planned to be deployed at the upcoming POTA event for a test-drive.
Ken provided insight into his efforts to locate a unique RFI phenomenon which plagued his 80m reception during last Christmas. Ken has had recurring experience with RFI and the cooperation needed by CenterPoint Energy services to mitigate or fix problems. Ken brought out equipment he had acquired during his activities to isolate RFI at this QTH, including a dipole broadband sniffer, an ultrasonic detector kit, a fox hunting 80m receiver, and a flag antenna build based on the QST March 2021 issue. Ultimately, his flag antenna was a highly effective device to sniff out RFI. It covered 2-60 MHz, flat SWR, directional, and exhibited extremely sharp nulls at the terminating resistor legs. Ultimately, his offending RFI was identified as a defective street light and CenterPoint was effective in the repair.
Dave brought out his assembled QCX mini transceiver build kit. ~$65 for the radio and $20 for the enclosure. The 20m single band CW small radio can be powered by a 9v battery and will be tentatively used in the upcoming POTA at Galveston Island on Saturday. The photo below was taken after the meeting.