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2.4 GHz opinion



>Date: Sat, 30 Dec 2000 09:05:11 -0600
>From: Gerald Payton N5GPC <n5gpc@earthlink.net>
>Also, it seems that most people are leaning toward the dishes for 2.4 gig.
 I'd
>like to seen a comparison between yagis, loop yagis and the dishes with
the same
>gain and noise figures.  Why would one be better than the other?  Is it the
>physical mounting ease?
>
>Jerry N5GPC

OK, Jerry and all:

In my opinion {based on what the experts have said} yagis and loop yagis
are not efficient above 1.2 GHz {though there are some commercial ones made
for 2.4G}.  Gain is more efficent to obtain and dish feeds simpler and more
efficient than the alternatives {evidenced by microwave links and sat-TV}.
At 2.4G I would guess that maybe a long helix might be equal to a small dish.

What I am using (or planning) {and more info than you ever wanted to know}:
{Brag mode=on}

Radios:  FT-847 and FT-817 (waiting for); DR-605T "mobile"

10m diamond-shaped "egg-beater" for RS-13 (planned)
15-17m dipole (planned)
20m ZL-special for "dc-band" (planned) beamed to "lower-48" USA
80-20m dipole {current RS-13 antenna} beamed to "lower-48" USA 
144 & 432 "K5OE Potato-masher" "egg-beaters" for digi-sats and...? (planned)
144/440 Cushcraft ARX-270 "FM antenna" {but heard 145.898 beacon just fine}
144 Cushcraft Ringo "packet"
50 HB 3-elem yagi on 22 foot pole/az rotator

on a 40 foot tower with az-el:
144 MHz:  four M2 xpol-20 cross yagis with switchable H or V polarity
{really my eme array}. mgf-1801 preamp (.15 dBNF)-->100 foot 9913 coax for
Rx--7/8 inch hardline for Tx
1.2 GHz: 45 elem H pol loop-yagi. fed with 100 foot of 1/2 inch
hardline<--DEM 144/1269 TXvtr. (20w)
432 MHz:  M2 420-50-11 V pol yagi "local ssb/FM" shares 1/2 hardline via
coax relay

on a roof-top tripod az-el: 
432 MHz:  M2 436CP42 CP yagi.  50w PA  and preamp located at the antenna in
wx-box-->35 foot 9913 coax.
18 inch DSS  offset dish:  dual-band feed (5turn 13cm helix/3cm circular
horn) (planned)
2400 MHz:  two Drake LNBs (122 & 432 IFs) (possibly with MK232 preamp)-->
35 foot RG-8/X
10 GHz (planned): DEM 10451/144 conv.-->35 foot RG-8/X

Other:
2.5 m dish (existing but not fully operational) 3cm and 13 cm
5m dish (planned install next summer) 23 and 21 cm
{Brag mode=off}

Whew!  (ought to put that on a signature line along with my resume ;-) he he

Ed
Oh, and for a hobby I have 12 sled dogs!

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