Yagi beam for pmr 446

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mof000
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Yagi beam for pmr 446

Post by mof000 »

Hello guys, i spotted this on the bay and thought it may be of interest to somebody looking into using a beam on 446. Thanks.
http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... 0339535939
I'll pay whatever i think it's worth...:-)
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Re: Yagi beam for pmr 446

Post by YB135 »

it can't be much cop if its got a PL259 (so239) connector and its for UHF......
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Re: Yagi beam for pmr 446

Post by MrWeetabix »

If it's home-made, then PL259 is probably the cheapest option....

I must admit to preferring PL259.....just because I'm lazy! :twisted: :mrgreen:
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Re: Yagi beam for pmr 446

Post by YB135 »

N-type for winners on vhf/uhf ;)
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Re: Yagi beam for pmr 446

Post by MrWeetabix »

Any gains made by using n-type would be cancelled out by my p*ss-poor assembly of the damn things! haha
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Re: Yagi beam for pmr 446

Post by bigbloke »

Interesting

Its basically an HB9CV (looking at the feed arrangements) with an added director.

I built a 5 element version of this for 2m back in the late 80's worked quite well.

I would expect, with the trimming cap, that this would tune 427-449 below 2:1 but I would think 100MHZ of bandwidth for TX would be stretching it a bit.

also the HB9CV uses a trimming capacitor, usually they are supplied with ones rated up to about 10w , suggesting that if you want to go higher power you use a co-axial capacitor (usually a "stub" of Rg-58) But I see no mention of that here.

Is it me, or do the elements look a bit too long for 430-450 though ??

Regards

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Re: Yagi beam for pmr 446

Post by kingmoff »

M6AXL wrote:it can't be much cop if its got a PL259 (so239) connector and its for UHF......
How much gain is lost between pl259 and N-Type... :? I think a great length of coax is more an issue at vhf/uhf, not the connector.
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Re: Yagi beam for pmr 446

Post by YB135 »

Wrong actually, you get more loss using the wrong connector. Obviously if you're using UHF you don't use RG213 let alone RG58!!!! Westflex 103 as a minimum on UHF bands.
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Re: Yagi beam for pmr 446

Post by StoatTB »

M6AXL wrote:Wrong actually, you get more loss using the wrong connector. Obviously if you're using UHF you don't use RG213 let alone RG58!!!! Westflex 103 as a minimum on UHF bands.
What would you recommend for a short 4 metre run of coax into a magmount or similar for mobile use - VHF/UHF?
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Re: Yagi beam for pmr 446

Post by bigbloke »

I Use Times LMR-200

Its similar sized to rg-58, but a bit stiffer

but good in short runs to 23 / 13cms (1300 / 2400 MHz)

all my vehicle mounts (bar the panoramas) are fed with it

regards

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Re: Yagi beam for pmr 446

Post by YB135 »

buggerlugs wrote:
M6AXL wrote:Wrong actually, you get more loss using the wrong connector. Obviously if you're using UHF you don't use RG213 let alone RG58!!!! Westflex 103 as a minimum on UHF bands.
What would you recommend for a short 4 metre run of coax into a magmount or similar for mobile use - VHF/UHF?
I'd recommend the best cable you can afford/work with. Coax is one of those things that people (in my opinion) don't take enough notice of. It can make massive db difference and the difference gets greater the small wavelength you go. I use rg213 for the mobile stuff as its better than rg58 but not too thick to get back in to the car if that makes sense...
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Re: Yagi beam for pmr 446

Post by StoatTB »

M6AXL wrote:
buggerlugs wrote:
M6AXL wrote:Wrong actually, you get more loss using the wrong connector. Obviously if you're using UHF you don't use RG213 let alone RG58!!!! Westflex 103 as a minimum on UHF bands.
What would you recommend for a short 4 metre run of coax into a magmount or similar for mobile use - VHF/UHF?
I'd recommend the best cable you can afford/work with. Coax is one of those things that people (in my opinion) don't take enough notice of. It can make massive db difference and the difference gets greater the small wavelength you go. I use rg213 for the mobile stuff as its better than rg58 but not too thick to get back in to the car if that makes sense...
I used to use RG-8 back in 1981 when I had an illegal (at the time) silver rod, then once I got back into CB in the early 90's I was using RG-213. It was good stuff, but a bit unwieldy at times - it did the job however. ;)
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Re: Yagi beam for pmr 446

Post by kingmoff »

M6AXL wrote:Wrong actually, you get more loss using the wrong connector. Obviously if you're using UHF you don't use RG213 let alone RG58!!!! Westflex 103 as a minimum on UHF bands.
Ok. Well done with the antenna 8)
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Re: Yagi beam for pmr 446

Post by mof000 »

I thought the antenna would be a good idea for taking portable with a hand held to help with getting a bit more distance than is possible with a standard antenna. I watched the video that Fez had done and was impressed by the distance that was achieved using a similar antenna.
I'll pay whatever i think it's worth...:-)
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Re: Yagi beam for pmr 446

Post by jazzsinger »

M6AXL wrote:Wrong actually, you get more loss using the wrong connector. Obviously if you're using UHF you don't use RG213 let alone RG58!!!! Westflex 103 as a minimum on UHF bands.
Westflex 103 has crap build quality in the shield,you'd be far better of using lmr or ecoflex coax,both have superior build quality even better at those frequencies would be hardline like andrew heliax or eupen hardline coax.the losses in connectors are minimal,about .2db,so using crap coax is gonna be far more lossy than using the wrong connector.
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