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Deans antenna on 50MHz.

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Deans antenna on 50MHz.

Old 01-31-2003, 04:36 AM
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Default Deans antenna on 50MHz.

Since Deans hasn't replied to this question maybe someone here can. I am assembling a Corona and will use a 50MHz. receiver (JR). The Deans antenna ads all state 72 or 75 MHz.. Anyone used or had problems with the standard Deans antenna on 50MHz?
Old 02-06-2003, 12:03 PM
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Default Deans antenna on 50MHz.

Judging by your signature line it might be time to get out the ARRL Antenna Handbook..

I'm after a similar answer except as to whether they make a 36MHz model for the Australian / European markets. If not then I guess I'll have to get out the ARRL instead !

I would think that the antenna has an inductor in it to load it specifically for 72MHz so it would not be optimised for 50. That said these things are hardly critical in there design, I think they say to leave 4-10" of original antenna pre Deans that is a fair variation in overall length at this (72) frequency.


Ingmar
(ex-VK2KEQ, gotta pay that renewal one day!)
Old 02-06-2003, 12:39 PM
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Default Deans antenna on 50MHz.

Ingmar,

When I got my Corona kit it had a US 72MHz Deans antenna in the box. This was no use for me as we use 35MHz in the UK but I noticed on the LMH "parts" list they had a "35MHz Deans" listed so I contacted them and arranged to swap. However Deb at LMH did say that they only had a "very limited stock" of the 35Mhz one left. I think it's just something like $9.99 anyway.

Only downside is that my package of bits took more than 2 weeks to arrive from the States.

However I've now recieved and fitted mine and it seems to work really well - one day I might actually get to fly this heli if the UK weather will calm down for a bit!!

Cliff
Old 02-06-2003, 12:46 PM
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Default Deans antenna on 50MHz.

Hmm.. so the mythical beast exists !

By the time the "fun police" (wife) let's me order the actual heli and mega b/l our weather will probably have turned from 40-45c to -2 !! Maybe I should spend my time playing with the radio gear and coming up with a design for a 35/36Mhz whip.

I read that your stuff took ages. I just received some Maxim IC samples which came via the "Royal Mail" from the uk and it took two weeks to Oz. That was standard post.

I guess when I place my order with Roffee it will take a week or two to get here, plus about AU$100 in freight. By shopping around I've saved a bundle though.

Ingmar
Old 02-07-2003, 12:06 AM
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Default Deans antenna on 50MHz.

Ingmar, thanks, and I have considered winding my own.

I was curious if anyone had used them and noted any degredation with helis. I routinely fly six meters with sailplanes, with occasional luck to spec out. The antennas on both the JR tx and rx are the same length as the 72MHz. flavorwith no noticable range issues.

For grins I will play with the Deans I have and various lengths between the it and the Rx with my MFJ analyzer to see what it looks like.
Old 02-07-2003, 12:23 AM
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Default Deans antenna on 50MHz.

I just received my reply from WCDEANS, they do still make a 35/36Mhz whip but they did not enlighten me with product codes etc. Just replied with "Yes!". I'll try my (not-so)LHS.
Old 02-15-2003, 09:07 PM
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Default Deans antenna on 50MHz.

In case anyone is interested I installed the 72 MHz. antenna, leaving 10" of wire from the receiver. Range cecks were similar to those done with the wire antenna.

I had done some measuremnts with an antenna analyzer and found that, like the transmitter and receiver antennas, it was not tuned for 72 MHz. either. In previous tests I've never found a reasonant antenna on JR, Futaba, or Hitec transmitters.
Old 02-16-2003, 04:49 AM
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Default Deans antenna on 50MHz.

I wonder what would happen if I did build a proper resonant antenna for 36MHz, maybe a base loaded whip and feed with mini teflon coax back to the input of the rx. That might be a good experiment. I'd probably have to bypass the loading coil that is already in the rx front end (if there is one!).

Ingmar

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