While studying things like resonant frequencies just for fun, I looked at the specifications on the TED monopole UAT antenna at Spruce.
I had to dig a bit on the manufacturers site. TED is in the connector business and has been for decades. Most builders are putting on a transponder antenna while doing their ADS-B upgrades. These are pretty broad coverage antennas and come from the era of transponders and DME units. Have you used a DME lately?
The antennas sold today range from monopole to high speed expoxy coated little blades that can go 1000 mph with a known drag coefficient. Yes, I exaggerate a bit on how fast I might expect my RV9A to go on a good day.
The surprising thing I noticed in the engineering specs for the little TED antenna was the resonant frequency of 978 mhz. The UAT units often put out 40 watts of RF energy at that frequency. For ADS-B in, there is not much concern for VSWR and complicated measurements. The ground stations are powerful and just about any antenna picks up weather and traffic pretty far from the station.
On the other hand, transmitting 40 watts at 978 mhz is a pretty good power burst. Comparing prices on all the offerings is what really surprised me.
Just my morning research while sipping hot coffee.
I had to dig a bit on the manufacturers site. TED is in the connector business and has been for decades. Most builders are putting on a transponder antenna while doing their ADS-B upgrades. These are pretty broad coverage antennas and come from the era of transponders and DME units. Have you used a DME lately?
The antennas sold today range from monopole to high speed expoxy coated little blades that can go 1000 mph with a known drag coefficient. Yes, I exaggerate a bit on how fast I might expect my RV9A to go on a good day.
The surprising thing I noticed in the engineering specs for the little TED antenna was the resonant frequency of 978 mhz. The UAT units often put out 40 watts of RF energy at that frequency. For ADS-B in, there is not much concern for VSWR and complicated measurements. The ground stations are powerful and just about any antenna picks up weather and traffic pretty far from the station.
On the other hand, transmitting 40 watts at 978 mhz is a pretty good power burst. Comparing prices on all the offerings is what really surprised me.
Just my morning research while sipping hot coffee.
