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Ziptip and Archer VOR ant question

Fenderbean

Fenderbean

Well Known Member
Just looking for feedback, I will be flying IFR and I know the VOR stuff is old but having the ability to do ILS/VOR type approaches will come up with my travels so better to have a not need than the other.

I was looking at the Comant VOR/ILS/GS since I believe it can be the same antenna for NAV1/2 but would rather run the Archer if it will do the same. Plus, I will need to mount the antenna on the Vertical which will require more mods now vs waiting till I'm on the wings.

I will be using he ZIPTIPs and wondering if the Archer will work in these due to the bottom light/overall design.

Thanks
 
The "cat's whisker", eye-poker antenna can be mounted on the vertical stab, and the output run through a mini-circuits ZFSC-2-1+ power splitter/combiner near the radios. From there each output will go to the respective NAV radio. If the NAV radio has a discrete input for G/S (like the GNS 430/530) then use a ZFSC-3-1+ and run one of the outputs to the G/S input.

I am not sure of the available volume in the ZIP tip, but the Archer SA-1 or any variant thereof will work fine and be made to fit. Same thoughts on the use of the splitter.
 
I run an Archer in the vans-standard RV-10 wingtip and am happy with its performance.
1. I think the lights in the ZipTips use pulse width modulation to keep the heat loading down. This has the potential to produce RF noise, only trying it out will tell for sure.
2. There is no need to mount the antenna near the leading edge. Move it back some, away from those lights.
3. It’s best if you can borrow an antenna analyzer from a ham friend, for final ‘tweaking’’, But probably not absolutely necessary.
 
I have the ziptips and plan on using an Archer NAV antenna in them. Plenty of others who have done it with acceptable results.
 
I have the Archer designed antenna in my ziptips on the RV-10. No issue whatsoever. Getting ranges of about 35-40 miles at 8,000 ft. Tracks localizers like a champ
 
Half wave dipoles (and quarter wave plus ground plane antennas) are naturally 3/2 wave resonant too (GS frequencies are 3 times localizer and/or vor frequencies). That said, the gamma match feed system used on the Archer will not be optimized at GS frequencies, so there’s some loss. But they certainly seem to work okay in practice. As noted above, you’ll need signal splitters and/or diplexers if you have dual navs and/or if they have separate gs inputs.
 
BobTurner said:
Half wave dipoles (and quarter wave plus ground plane antennas) are naturally 3/2 wave resonant too (GS frequencies are 3 times localizer and/or vor frequencies). That said, the gamma match feed system used on the Archer will not be optimized at GS frequencies, so there’s some loss. But they certainly seem to work okay in practice. As noted above, you’ll need signal splitters and/or diplexers if you have dual navs and/or if they have separate gs inputs.
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Yup - don't expect to get G/S valid 50 miles away ;) In practice the G/S flag goes away and you pick up "lobes" on the PT outbound.
 
Fenderbean said:
Will it provide ILS/GS?
Click to expand...
Despite all theory, I measured the Archer antenna and it does not have any resonance at 330 MHz for the GS signal. However, today's radios are so good, they can still get a good signal from it. Older NAV receivers might have issues with it.
Nevertheless, I designed an add-on for the Archer antenna that screws onto the two terminals and provides a secondary arm with GS resonance. This modification doubles your GS range. I have attached the dimensions.
 

Attachments

ewumnrr said:
Despite all theory, I measured the Archer antenna and it does not have any resonance at 330 MHz for the GS signal. However, today's radios are so good, they can still get a good signal from it. Older NAV receivers might have issues with it.
Nevertheless, I designed an add-on for the Archer antenna that screws onto the two terminals and provides a secondary arm with GS resonance. This modification doubles your GS range. I have attached the dimensions.
Click to expand...
Awesome, I will check it out. This seems the best bang for the buck, and always cool to see what people do to make things better.
 
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