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ADSB Antenna

g zero

Well Known Member
I’m considering a Garmin GTX45R transponder…..if they are available soon . It’s a ADSB in / out . Looking at Antenna options . Will a basic TED Antenna or a Delta Pop be compatible ? Also trying to find out the Maximum RG400 cable length to the Antenna .
 
I’m considering a Garmin GTX45R transponder…..if they are available soon . It’s a ADSB in / out . Looking at Antenna options . Will a basic TED Antenna or a Delta Pop be compatible ? Also trying to find out the Maximum RG400 cable length to the Antenna .

A basic TED Antenna will work just fine. A Delta Pop will work "better" but unless you are in a laboratory with specialized test equipment you won't notice any difference. Regarding the RG400, our airplanes are not big enough for cable length to be an issue. Especially your RV8. Just keep it reasonably short.

:cool:
 
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Antenna

A basic TED Antenna will work just fine. A Delta Pop will work "better" but unless you are in a laboratory with specialized test equipment you won't notice any difference. Regarding the RG400, our airplanes are not big enough for cable length to be an issue. Especially your RV8. Just keep it reasonably short.

:cool:



Hope all is well Galin . Tried St Aug 2 weeks ago …. Tower Issues VFR/ IFR .

Regarding Cable length…. My 8 has all of a 40” run ….this is a new build . I’m probably 12 foot but would like to go 15 foot …… thoughts ?
 
Will a basic TED Antenna or a Delta Pop be compatible ? Also trying to find out the Maximum RG400 cable length to the Antenna.
I use the DeltaPop transponder antenna with my 45R, works great! The TED antenna should work as well, but I'm sure I go at least 10 knots faster with the streamlined DeltaPop antenna! :p Plus, Don Pansier puts a lot of work into his antennas and I'm happy to pay for quality products from a fellow RV builder.

IIRC from the 45R install manual, the maximum allowed coax length for RG400 is 8ish feet but check the manual to be sure.

HTH

Dave
 
I’m considering a Garmin GTX45R transponder…..if they are available soon . It’s a ADSB in / out . Looking at Antenna options . Will a basic TED Antenna or a Delta Pop be compatible ? Also trying to find out the Maximum RG400 cable length to the Antenna .

+1 for the Delta Pop Ultra Low Drag antenna...

Max cable length for RG-400 at 1090MHz is < 9ft (assuming published losses at that frequency, connectors, etc.)
 
Hope all is well Galin . Tried St Aug 2 weeks ago …. Tower Issues VFR/ IFR .

Regarding Cable length…. My 8 has all of a 40” run ….this is a new build . I’m probably 12 foot but would like to go 15 foot …… thoughts ?
Man, next time you heading this way give me a buzz. I was supposed to be at Flagler yesterday but got rained out REAL bad.

12-15ft is a bit long for an RG400 cable run at 1090Mhz. At 15ft you are looking at 2.6db of attenuation, not a huge issue for transmit but significant for receive. If you absolutely have to be 15ft away, then you should use LMR-400 which would only have .8db loss at 15ft. But the price difference between LMR-400 and RG400 can be quite large. IMHO you are much better off getting the Xponder and antenna closer together so the cable run isn't that long.

If it is a new build I would install the remote Xponder box as close to the antenna as practical. That is how I have mine. My remote Xponder box uses 18" of RG400 to the the antenna with RS-232 wire from the remote Xponder box to the instrument panel.

:cool:
 
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Output power requires 125w minimum to be legal.
From the 45r manual:

Transmitter power
125 W min at antenna, with max 2dB cable loss 250 W nominal at unit.
(2db= Approx 12’)
Connectors can add about .5db loss so that brings cable length to about 9’ max.

If you want the best “IN” performance a wideband antenna like the DP or Comant CI-105 is required (as noted in the install manual).
 
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ADSB antenna

I appreciate all the help. Based on the answers I’ve moved the antenna location… now I’m at the minimum length of RG400.
Thanks
 
I appreciate all the help. Based on the answers I’ve moved the antenna location… now I’m at the minimum length of RG400.
Thanks
Cool. I will call you next time I am near KFIN and maybe we can meet up so I can see what you are building now. :cool:
 
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