03/22 QSO EXPO Intermediate Buildathon - Switched Inductor TunerPrice: $35.00
ATTENTION! As of Thursday 03/10/2022 Even Priority Mail shipping now has no time frame to get them to their destinations in time for the Saturday & Sunday Buildathons so I cannot guarantee delivery by Buildathon time! I changed the S&H cost back to *normal* First Class mail. It is unlikely a kit order now will arrive in time to build during the LIVE stream Buildathon session. It usually takes about a week for the live stream video to make it up onto the QSO Today post EXPO website. Once it does get there, it is available for 30 days so you can still build the kit using the video as a guide. Order your kit with this in mind.
The Switched Inductor Antenna Tuner is a tuna can based kit updated for the QSO Today HAM EXPO intermediate Buildathon to be held on Sunday March 13.
The Switched Inductor Antenna Tuner is used to modify the feedpoint impedance of SOME wire antenna configurations in order to match them to the 50 ohm transmitter impedance. Matching the impedance of antenna to the transmitter maximizes the transmitter output. The wire antennas of interest here are typically off center fed 1/2 & 3/4 length dipoles used in portable QRP operation.
It is a fairly easy kit to build even by novices BUT there is a toroidal transformer to wind! Axial inductors are switched in and out which along with tuning from a polyvaricon capacitor to tune unique configurations of these wire antennas.
More information and documentation will follow as it is being currently developed. The schematic included in the link below is the actual kit while the TTH Builder*s guide is for the original kit that I have been selling for many years. My original kit used some VERY GOOD and VERY expensive switches which is why it was one of my most expensive tuna can kits. I redesigned my original Tuna Tunah ][ kit specifically for this Buildathon when I found a source for some more reasonably priced switches.