Show & Tell November 2023

  • VarAC by Ray G4FFY
    Ray brought his Icom IC-705 & ASUS laptop to show a new keyboard to keyboard chatting mode called VarAC, featured in the May 2023 RadCom which gives the details of this mode, setting up, and operating. Of the screens that the mode produces, he showed VARA-HF, a modem to manage the communications link on the HF bands, derived from the popular RosModem EA5HVK. There are also versions for VHF/UHF VARA-FM, and VARA-SAT for QSO’s for QO-100. Another screen was VaraAC, a Client application that uses the VARA modem to provide the communication link. The name is derived from combing the founders callsign 4X1AC with the Vara modem. VaraAC’s role is to add all the bells and whistles that transform a simple communication link into a feature-rich data mode.
  • Portable Data Mode Station by Matt M0CUV
    Matt M0CUV showed his compact portable QRP data modes station – works on 14/18/21/24/28 MHz, and any single-tone FSK mode, which covers the majority of digital modes in use today. Best DX so far with 3.5W is RK4FF via FT8 – almost 3000km away!
  • Battery Testers by Malcolm G4FWG
    Malcolm showed these simple but effective devices for testing batteries
  • Milsim kit by Jez M7EFB
    Jez’s Milsim kit has a Clone Harris radio (TCA AN/PRC 152) running into a PTT and into a peltor Comtac XP headset to keep in contact with his team during exercise operations
  • Antenna for a small garden by M0ZWW
    Emphasising what can be done effectively but simply, Billy had brought a 20m sleeve antenna, made of coax with the braid stripped off a quarter wavelength and an air-cored line choke formed of 12 turns a further quarter-wave down the coax feeder. Heat-shrink sleeving sealed the braid where it had been stripped back to stop moisture ingress. When hung from a fibreglass pole, it’s an effective half-wave centre-fed vertical dipole that’s very accessible to adjust in situ and requires no radials but can give DX from the smallest of gardens or SOTA portable. When trimming it for resonance, he cautioned that the choke position would need to be adjusted similarly to keep the dipole legs equal.
  • Novel Crystal Set by G3MGQ
    Phil showed a novel crystal set, built from a kit won in a radio club quiz, featuring a valve diode as a cold-cathode rectifier with a traditional cat’s whisker and a germanium diode for comparison.