SMALL - espritmodel.com SMALL - Telemetry SMALL - Radio
Reply
Thread Tools
Old Aug 13, 2003, 08:44 AM
Registered User
Perth, Australia
Joined Jul 2003
99 Posts
I need help to DIY flywire antenna for 36 MHZ RX

I bought a Dean's flywire for USA just to find out that it's frequency specific. It's for 72 MHz. I look everywhere on the internet but no one sell 36 MHZ flywire. I don't even know if they make one. Australia RC uses 36 MHZ also 29 MHZ. I have 36 MHZ radio and I like to know if anybody know how to calculate the component for a DIY flywire. This site by Tony has a DIY disgranm but doesn't mention about frequency but I think it's for 72 MHZ: http://www.uoguelph.ca/~antoon/gadgets/flywire.htm

Can anybody help please.
GoodHeli is offline Find More Posts by GoodHeli
Reply With Quote
Sign up now
to remove ads between posts
Old Aug 13, 2003, 09:13 AM
Registered User
vintage1's Avatar
East Anglia, UK
Joined Sep 2002
29,689 Posts
Frankly, since it depends utterly on the receiver you use - not just the frequency - you could probably start with a 2.2, 2.7 or 3.3uH choke and see what works best.

Ive been meaning to try some of these - but I get adequate range with the antennas folded up inside the wings or fuselage so I haven't bothered.

35/36Mhz antennae are still about a meter long typically, which is nowhere near tuned for the frequency, so cutting em about a bit doesn't make a whole lot of difference.

My guess is you might bet 2-3 times the range from a shortened antenna with the right sized choke in versus a simply shortened one.

Best way to test is put the model on a table, and try the various things out with the TX antenna down - and use whatever works the best. Do it with the proper antenna first. That gives you a baseline for range.
vintage1 is offline Find More Posts by vintage1
Reply With Quote
Old Aug 13, 2003, 10:26 AM
Registered User
Perth, Australia
Joined Jul 2003
99 Posts
I wonder if the 72 MHZ whip antenna will works okay for 36 Mhz. I learnt about 1/4, 1/2 & 1 sine wave things on ham radio site. 36 Mhz x 2 = 72 Mhz. Don't know if this makes sense, I am just mostly doing this by a calculated quess. I'll be using this on my heli and I don't fly it far away like my glider but I still want make sure it works for safety reason.
GoodHeli is offline Find More Posts by GoodHeli
Reply With Quote
Old Aug 23, 2003, 08:35 PM
Registered User
Monument, CO
Joined Apr 2002
343 Posts
36 mhz short antenna

There are 2 mfgr's on here that advertize short antennas One is Azar, and the other is Jims light-tenna. Search for them. I know that Jim is working on a 35/36 mhz version, and I think that Azar has one in his products.
john
fumblefingers is offline Find More Posts by fumblefingers
Reply With Quote
Old Aug 24, 2003, 03:14 PM
Registered User
Colonial Heights, Virginia, USA
Joined Mar 2001
1,710 Posts
to salvage your USA type Deans, you can probably get good enough results by near doubling the length of wire parts "A" and "B" of your 72 mhz instructions.... do some close-in test flights and be prepared to chase after your bird if out-of-range glitching occures.... it's probably not that critical unless you're doing extreme range flying......... kw
KillerWatt is offline Find More Posts by KillerWatt
Reply With Quote
Old Aug 24, 2003, 08:05 PM
Registered User
Colonial Heights, Virginia, USA
Joined Mar 2001
1,710 Posts
or just doubling part "A" length to make it more of a base loaded type antenna which is more effective in electrically lengthening the antenna as compared to the original's near center load design....... kw
KillerWatt is offline Find More Posts by KillerWatt
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Need help with Motocalc #'s for speed 300 7.2v roguewolf Power Systems 2 Apr 20, 2003 01:19 PM
Need help--Airtronics Vision programming for electric joeflyer Radios 0 Apr 01, 2003 09:36 PM
Need help on wing placement for correct CG Flyinmonkey Sport Planes 3 Feb 11, 2003 01:55 AM
Need help with Airplane books for 12 year old 1987tc Electric Plane Talk 2 Dec 16, 2002 10:42 AM
Need help programming throttle stick for both throttle & spoilers pik20 Electric Sailplanes 0 Jul 12, 2002 12:48 PM