G.Beat wrote:
"AO KD5FXT" wrote in message
...
What abt using my 13B2 for us on 440? I don't have an analyzer for that
band
nor a swr meter. What are the thoughts on this? I have a friend in
Houston
who does it and verifies it to be ok. Responses and thoughts appreciated.
Seem like a waste of a good Cushcraft 13B2 (13 element yagi) 2 meter antenna
($ 150 MSRP)
for 440 MHz antenna. http://www.chq-inc.com/cush/13B2.html
What are you trying do on 70 cm ? (440MHz) SSB/CW DX, FM repeaters, ATV,
satellite work
1. When you move from 2 meters to 70 cm -- the coax you use from you
operating position to the antenna
becomes much more important than at HF or low VHF frequencies.
For example, for 100 feet of coax the attenuation in dB [from Cable X-perts
charts]
http://www.cablexperts.com/cfdocs/ca...ub=0&bskt=0&US
A_ship=1&c=0
RG-213/U at 150 MHz - 2.8 dB; at 450 MHz - 5.2 dB
LMR-400 at 150 MHz - 1.5 dB; at 450 MHz - 2.7 dB
2. Some designs to consider !
K5OE 70 cm yagi designs (in this case for AO-40)
http://members.aol.com/k5oe/P3D_ant/P3D_yagi.htm
VK3KHB 8 element design for ATV usage
[Uses 1/8" (~3 - 5 mm) solid rod for elements and round or square aluminum
tube (~ 10 mm)
http://www.gak.net.au/vk3khb/atv/antdesign.htm
WiMo products [Germany] - great for ideas
http://www.wimo.com/verteiler-e.htm?s1_e.htm
KK5UFO designs
http://www.homestead.com/kk5ufo/VHFbluprint.html
XE1MEX design (for 2m and 70cm)
http://xe1mex.gq.nu/antenas/yagi.html
Martin DK7ZB very nice designs
http://www.qsl.net/dk7zb/start1.htm
Derek, G4CQM
http://www.g4cqm.btinternet.co.uk/an...gner/yagis.htm
That's a start !!
w9gb
Also the 'VHF/UHF Long Yagi Workshop' on my site.
--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)
Editor, 'The VHF/UHF DX Book'
http://www.ifwtech.co.uk/g3sek