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By letpmar
#1616262
Two questions
I am thinking of setting up my spare handheld a bit more permenantly in my aircraft. I always take it on European trips and it earned its money on my last trip when what I am now calling box one (don’t i sound posh) failed. I will probably not run it through the intercom but I will probably sort power and it’s own antenna. It will only ever be one or the other.
1
If I fit a second antenna and join the two together, will that give me more radio range on whichever unit I am using.
2
Is my redundant VOR antenna any use (radio or Pilot Aware) the cable is still in and I could always fit the second antenna to replace the VOR one in the tail.

Thanks in advance
Last edited by letpmar on Thu Jun 07, 2018 12:17 pm, edited 2 times in total.
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By PaulSS
#1616270
1. Your radios only chuck out so much power. Having that signal split between two antennas is not going to up the range......in fact it will do totally the opposite. You could combine both radio coax cables into a splitter and use the one aerial but it's not ideal.
2. Your VOR antenna is tuned for a different frequency than the VHF RT. You may be okay with some of the lower frequencies but it's not going to be brilliant. By SkyDemon I assume you mean ADSB? In this case, no, that's way off for tuning.

If you've got decent coax to the VOR antenna then you'd probably be better off just installing a new VHF radio aerial in place of the VOR and connecting that to your handheld. Keeping the two radios separate gives you redundancy and doesn't muck up your existing radio with trying to split coax cables etc.
By User72
#1616454
Agree, a second aerial is going to do no good and will potentially be detrimental. Would caution against connecting both radios to one aerial. That will feed the transmitted power of the panel mount directly into the handheld receiver, which might not cope.

Using a VOR aerial will provide poor performance. It is not so much about frequency (VOR freq is close to VHF) but about polarisation. VOR signals are horizontally polarised, so the aerials are horizontal. Comm radio signals are vertically polarised, using a horizontal aerial will provide poor performance.

If you will only ever use one radio, with the handheld as a back up, you could install a male/female break in your aerial feeder that is reachable from your seat. If the main radio blows up the break the connection and connect the handheld. However, I think I would be spending money on making sure the panel mount was reliable rather than how to connect the handheld when the panel mount expires.
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By PaulSS
#1616461
Some good points from User72, which add to your inability to use the VOR antenna for anything else.

No, sorry, but it won't be any good for Pilot Aware either. 869.5MHz, whereas your VOR antenna is set up for 108-118(ish) MHz.
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By Paul_Sengupta
#1616472
It could make a good receive antenna for ADS-B. The inefficiencies of tuning will be made up for by being multiple wavelengths and being out in the open. So instead of receiving stuff 100 miles away you can receive stuff 200 miles away! ;-)
By letpmar
#1616501
Thanks for all the useful points. The radio has been very reliable, it was only a break in the headset socket wire. I do a lot of long trips into Europe and always think a spare radio is worth taking. A splitter or it’s own antenna will be easy to fit and I will probably fit a ram mount for somewhere to keep it.
On the VOR antenna side I was more thinking that I have a Coax cable still in, so perhaps I could make use of it. I did not expect the antenna to do much. I will permenantly fit Pilot Aware at some stage so did wonder about using the cable to stick one of the antennas on the tail. Which of the two would be best on the tail if any.
Thanks

Pete