Balloon Antenna Success
by Tyler Costantini KBØPQP
The balloon antenna worked very good what was surprising was the broad tuning range. The antenna was a 1/4 wave at 160m but we never measured the length we just used the antenna analyzer. It was first fed with a random wire tuner at the base that didn't provide a very good match. Next we just used a BNC to banana adaptor and put the wire right in the end of the 50ohm coax which lead to my MFJ 989c tuner that setup worked great. We could tune 160-20 no problem any part of the band and it seemed to radiate well. We put a 2mH choke between the radial and ground to act as a DC ground to remove static. I couldn't notice any change in the behavior of the antenna with the choke in place so I guess my math worked. It's 50+ turns in a FT-240 type 43 toroid.
The antenna started out around 30deg and we later got it to about 65 deg with improved the signals quite abit. I could hear multiple AM broadcast stations on every 10khz step. WWV was 60+ S9 on 2.5,5, and 10mhz around a S9 on 15mhz. We made many contacts on 80,40 on the antenna. We heard stations in 160m but with the storms to the west the noise level was 20+ 9 so we didn't make any contacts.
Well what surprised me the most was the good match on 80,40, and 20 without a transformer at the base. This picture below is earlier when it was at about a 30 deg angle we got it up to roughly 65 deg later
A New Moon ?? |
Be sure and watch this video..... it has a GREAT ending !!
I told them that a hydrogen balloon would make a big bang, but they said it would just make a loud whoosh.
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