Anyone using this unit with your handheld VHF Radio?

[Greg Mitchell]

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[aussie_paul]

Greg, those are the only antenna that work in most situations. I have used a dozen of them from Microair successfully.Aussie Paul.

[Disco]

i
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[bones]

there is one better for a full fibreglass cabs, it is the aero-whip, i think skyshop sell them for about $250, can not be used near any type of metal or allu, but other than that great.

[Greg Mitchell]

Thanks Fellas,I saw the whip for fibreglass cabs, it can be partially looped inside the front end...I dont have a pod.Reckon I"ll try this.Cheers,Mitch

[chook]

Greg, Before you mount it permanently, try and get someone with a SWR (standing wave ratio) meter to help you find the best spot on you gyro. I have put the SWR meter in circuit and taped it onto various locations around the gyro to find the "sweet spot". And its surprising where it may end up. I find them most successful around the wheel supports except that this will favour one side of the gyro over the other for efficiency.

[Greg Mitchell]

Greg, Before you mount it permanently, try and get someone with a SWR (standing wave ratio) meter to help you find the best spot on you gyro. I have put the SWR meter in circuit and taped it onto various locations around the gyro to find the "sweet spot". And its surprising where it may end up. I find them most successful around the wheel supports except that this will favour one side of the gyro over the other for efficiency.

[Adrian S]

Mitch,Google Mobile One Air Kit and buy direct from manufacturer, OZ firm that sells ground independent vhf antennna tuned to our airband and optimised for 118 to 136. Closest thing to plug and use that I know and only @ $125 . I have now standardised on this for all open aircraft that I install comms in. Chook is spot on re using the SWR meter to identifying the best location. When doing this make sure your engine is runing and all lights are turned on.Just my 10c worth. Adrian

[Greg Mitchell]

Thanks Adrian.Talked to them today.

[asra]

Here is a picture of the Dipole I bought from Mobile One. I mounted it with the ground antenna hidden in the pod. I did SWR it and found when mounted truly vertical instead of on an angle, it gave me the lowest and best SWR readings.http://www.mobileone.com.au/antennas...nd.htmlRegards SamL...................

[chook]

Greg this radio stuff is a bit of a black art. Just to clarify my statement by shifting the antenna a couple of mm to the left or right of your designated mounting location can significantly change the reading on the SWR meter.And yes home made can be very effective - the last one I built had amazing figures but it took me 9 hours to get it that way and I had borrowed a 12 grand piece of test equipment for the weekend to do it (In a previous life I worked in Telstra mobiles).Adrians suggestion is the easiest for you, the only other trick is to obviously do it in the open and well away from any buildings (50 - 60m). With these SWR meters you will even notice a change depending on where you are with relation to the antenna - yes its that tricky.Keep me posted on your progress or email me (see my profile) if you get horribly stuck. You should have come over for the nationals to WA. We pulled several gyros to pieces including the SWR tests. (Ask Hatrack!)

[Greg Mitchell]

Thanks Chook, I appreciate the offer of help.I"m off to town today, may end up buying some bits and pieces and try the PDF file unit.If unsuccessfull, I shall try the MobileOne AIRKIT.Last Night I see Colin Gibson posting on the Yank forum (he"s a Kiwi) He stated he bought the Mobile One Unit, threw away the bottom piece and added a piece of stainless same length as the main aerial and it works great.Based on that, I decided to make the home made job first.For sure I"ll give you a call if I struggle with it.Cheers,Mitch

[Greg Mitchell]

Went to town today for an MRI, then did some shopping. Launceston, Tasmania is not a big place really and I have always struggled to get even basic stuff for the gyro. Didn"t have high expectations.Hit the local UHF CB Radio Tech Shop and came home with:-2.5 meters of PEI RG58 C/U Mil-C-17F1 BNC Panel Mount Connector (Bloke said he wouldn"t have one,came back with the unit, said we don"t normally stock these)2 BNC Coax End Fittings1 BNC Aerial Adaptor (Screw type)Bloke in the shop fitted up 6 feet for me. Rigged/crimped the whole RG58 coax, connected it to my radio via the BNC aerial adaptor. Had him give me a couple extra feet for working up the Balun.Cost $33.50 that included the GST (all taxes)He was "keen as mustard" to hear how the project comes along. Told him I would mount it up front initially and see how I fare.Joy of Joys, he has a SWR unit and will let me park the gyro up and do the job on it to find the optimum spot. This will work, as he is in a large industrial area, so the noise of the gyro wont bring to much attention, whilst testing.I will advise when I have the aerial ready for testing.Thanks to all.Mitch.

[Greg Mitchell]

Had a nice flight yesterday before I mounted the aerial, as a storm front was apporaching.I"m getting incomming from 400 kms away and ground test have proved comms is excellent over good distances.Have mounted it up front as a proof of concept and will likely end up mounting it, partially imbedded perhaps,

[chook]

Greg, I"m assuming that your install is the black "stick" coming out of the top of the instrument pod.It is better to try and get the "stick" vertical when you are flying. That"s what the term vertical polarisation means - all of the antennas should be pointing in the same plane ie other aircraft, the tower, ground stations and your own aircraft installation. Next test - the VSWR from the radio guy.Incidentally if you want to know what he is doing when operating the meter, have a look at http://www.xcomavionics.com/manuals/...structions.pdf. They have an excellent description as well as what to do if the reading is not as good as it should be. Be careful if you get to the "trim the antenna" bit. Cut half a millimeter and retest. Be patient - I"ve seen half a millimeter do nothing until you"re right on top of the "sweet spot" then bingo.Ok I"ll bite - whats the "V" antenna above the nose wheel for?Chooky