Topband: MA160V SWR/match

[Hardy Landskov]

The antenna driven element also has to be capacitive. The ideal Z for a 
hairpin match is 25 - j25. A good tutorial is given starting on page 26-11 
of the 20th edition of the ARRL Antenna Handbook.
Hardy N7RT

----- Original Message ----- 
From: "John Tait" <bravo at iol.ie>
To: "Kenneth Silverman" <kenny.k2kw at gmail.com>
Cc: <jcjacobsen at q.com>; <topband at contesting.com>; <bryonveal at msn.com>
Sent: Thursday, August 11, 2011 4:17 AM
Subject: Re: Topband: MA160V SWR/match


> On 10/08/2011 21:04, Kenneth Silverman wrote:
>> <SNIP>   You could also try 10 or 12 turns of #12 or 14 gauge wire, 2" 
>> diam
>> across the feed point and ground.
>> Spread/compress the turns to get the lowest SWR/best match.
>>
>> Just to be specific:  this "hairpin" match only works if the antenna
>> feedpoint impedance is lower than 50 ohms,  The hairpin is an 
>> up-tranformer
>> of impedance (low to high transformation) and thus works for typical 
>> short
>> verticals which often have very low impedances.
>
> If it improves your match, you also gain the advantage of having the
> vertical grounded..thus giving you less static and noise to contend with
> on receive.
>        Good luck, es vy 73
>              John EI7BA
>
>
>>   If the ground system is
>> poor and the feedpoint happens to be above 50 ohms (indicating a lot of
>> ground loss), the hairpin will further increase the impedance and make 
>> the
>> SWR worse.
>>
>> Kenny K2KW
>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK