Make your own UHF antenna's

[MrBen]

Dont be lazy follow this guide for Monopole (Sander style)

http://fpvlab.com/forums/showthread.php?382-Sander-style-(Ez)UHF-antennas&s=936954d9675d3fb11308bfc336f7e618

Antenna tube here

http://www.ebay.co.uk/sch/i.html?_trksid=p2047675.m570.l1313.TR0.TRC0.Xantenna+tube&_nkw=antenna+tube&_sacat=0&_from=R40

Right angle SMA here

http://www.ebay.co.uk/itm/5pcs-SMA-male-right-angle-plug-crimp-for-RG58-LMR195-RG142-cable-Connector-/151026059359?pt=UK_Mobile_Phones_Communication_Coax_Cables_Connectors&hash=item2329dac85f

You can use a piece of servo wire or even piano wire for the antenna itself and some 5mm heatshrink to hold the tube to the SMA, the tubes I have been buying off ebay fit snug inside the SMA nicely.

If you want to make a Dipole then you need to buy a SMA pigtail like this http://www.ebay.co.uk/itm/SMA-male-to-SMA-plug-straight-pigtail-cable-RG316-30cm-/290653492519?pt=UK_Computing_Boosters_Extenders_Antennas&hash=item43ac4c5527

Dipole build thread on FPVLab http://fpvlab.com/forums/showthread.php?3156-433MHz-Half-wave-dipole-for-LRS&highlight=dipole

[Dusty]

I made a monopole sander style the other day, I have lot's of those right angle connectors.

but it only gave 15 paces of range in micro mode range test, compared to 60 with the dipole.

but the next day I did another micro mode range test with the dipole, and only got 15 paces again.... more testing and fiddling and turns out the sma connector on the TX unit is at fault, not the antenna.

these are very simple to make, all you need is a small enough tip on your soldering iron to get into the sma connector.

[brodjackella]

I made a dipole using the right angled sma pigtails linked above for maxi wing.
stripped coax back for tuned length and used the twisted coax for ground plane all enclosed in some straws.
testing using the Emmersion tools rrsi  showed average 5db better than stock EZ antennas which is almost twice distance in range...

[MrBen]

I would say use a monopole on a multirotor or a smaller plane and a dipole on anything as big as a zephyr or skywalker. A monopole should still get you out to around 10km.

[MrBen]

1st post now includes link to dipole build thread.

[motofox]

are dipoles definatly better ? im thinking of one on the tail and one up front of the plane.

[MrBen]

yes however not needed if you are staying within a few km, i wouldnt use them on small planes or quads, a normal whip style antenna should still get you 10km on UHF

[Dusty]

The items listed above, to make these antennas, usually come in multiples... they're too small/cheap for it to be worth buying single items.

I did have the bits, but have lost the nylon discs and the brass screw caps for the right angle connectors so I've ordered new connectors.

I've got the wire soldered to the pin inside the connector, and have cut the wire to correct length (as per instructions in that link) antenna tube is on but I'm just waiting for those screw caps before they're ready.

I will have a few spare if anyone's interested.

[Dusty]

I've used insulated servo wire on one antenna, and copper enamel wire on the other. I'll do a micro mode range test with my rangelink and see which one comes out on top.

[londonguy]

You really need to put a ferrite on a dipole. They will work without but the performance is not as good.

The ferrite should go immediately after the antenna itself, ie on your extension wire.