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IZ3LSV

[San Dona' di P. JN]

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UT1HZM > ALL      09.02.10 14:52l 26 Lines 935 Bytes #999 (0) @ WW
BID : 44132_UT1HZM
Read: GUEST
Subj: Re: 144 Mhz 5/8 50 Mhz 1/4
Path: IZ3LSV<IW0QNL<ON4HU<DB0RES<DB0OVN<DB0IUZ<DB0FBB<DB0ERF<DK0MNL<UT1HZM
Sent: 100209/1333Z @:UT1HZM.KREM.POL.UKR.EU #:44132 [Kremenchug] FBB7.00i
From: UT1HZM@UT1HZM.KREM.POL.UKR.EU
To  : ALL@WW

g4azb asked:

>I have been told that a 5/8 wave 144 Mhz vertical works as a 50 Mhz
>quarterwave, has anyone any experience of using such a set up ?.
>Many thanks,
>Steve

Its should be possible, if 2m 5/8 antenna have coil exactly in series
between coax center conductor and bottom of radiating element. 

In this case series coil works on 2m to compensate impedance reactive portion
of 5/8wave 2m band whip. On 50MHz this coil work just to extends length for
resonance of 1/4 for 6m band. Note that you need at least 2-3 radials for 6m
band to have low SWR and good radiating pattern. If this is whip on magnetic
base, possible addition radials is not need, just coupling with car case will
enough.

But I'm not sure that is possible for case if 2m 5/8 antenna had
autotransformer match (coax center connected to the tap of coil, that in
series between whip and radials)

73, Sergej


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