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ZL1ANM > RIGS 14.07.03 17:02l 32 Lines 1272 Bytes #999 (0) @ WW
BID : ZL1ANM314987
Read: GUEST DB0FHN
Subj: Re: Why not ssb handhelds ?
Path: DB0FHN<DB0RGB<OK0PPL<RZ6HXA<IK1ZNW<ON0AR<VK3TE<ZL2BAU<ZL2BAU<ZL2WA<
ZL1AB
Sent: 030714/0048Z @:ZL1AB.#11.NZL.OC #:40498 [AUCKLAND] FBB7.00g25 $:ZL1ANM314
From: ZL1ANM@ZL1AB.#11.NZL.OC
To : RIGS@WW
Kathy VK4XYL wrote:
>Needless to say, there was no-one else around, so no contacts were made,
>but the system was certainly viable! ....
Not necessarily. SSB operation on 144.2 usually involves home stations
running horizontal polarization. Handhelds are usually held upright with
a vertically polarized rubber ducky.
Polarization incompatibility results in a path loss of 20 to 30 dB.
20 dB is a power multiplication factor of 100 times. 30 dB is 1000 times!
Consider two stations in contact, both running 2 watts with horizontal
dipoles. Now assume one of the stations changes to vertical polarization
with say, a ground plane. Both stations must now increase power to at
least 200 watts, and possibly 2000 watts, just to remain in contact!
The situation is even worse with inefficient rubber duckies. You can see
that handheld operation with a rubber ducky is not really viable, unless
the distant station is also vertically polarized (and most are not!).
73 de Neil, ZL1ANM @ ZL1AB.
486/66 (dos 6.22)
T4 packet program/TFX --> homebrew modem (Tx: 2206 PLL chip)
(Rx: 565 PLL --> LM324 buffer).
T4 1.5à24
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