I need help to DIY flywire antenna for 36 MHZ RX - RC Groups
Aug 13, 2003, 09:44 AM
Registered User

# 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

 Aug 13, 2003, 10:13 AM Registered User 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.
 Aug 13, 2003, 11:26 AM Registered User 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.
Aug 23, 2003, 09:35 PM
Registered User

# 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
 Aug 24, 2003, 04:14 PM Registered User 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
 Aug 24, 2003, 09:05 PM Registered User 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