Topband: Hairpin Matching Coil Questions

[Charlie Cunningham]

Great!

I like the spark gap and the 33K static drain much better between the
antenna and ground, that between the antenna and radials as in your first
post! I was thinking of sending you a note to that effect, but you saved me
the trouble, Mike! 

I expect that your capacitor matching network tunes rather nicely!

73,
Charlie, K4OTV

-----Original Message-----
From: Topband [mailto:topband-bounces at contesting.com] On Behalf Of Mike
Waters
Sent: Tuesday, September 17, 2013 5:51 PM
To: W2RU - Bud Hippisley; topband
Subject: Re: Topband: Hairpin Matching Coil Questions

Ok, I found the photos, and I see that I need to take new ones of the
present arrangement. But here's the capacitor values in the L network.


 - Between the 75 ohm coax center cond. and antenna: 350 pF variable,
padded with a 200 pF fixed.

 - Between the antenna and the junction of the radials and coax shield, 430
pF variable.


I used what I had available, and I forget where the capacitors are actually
set.

I think the radials are 132' long. The inverted L is 155' total, about 55'
is actually vertical. The rest slopes down to the end insulator and
counterweight through a pulley, to allow for the trees swaying in the wind.

Correction to the last post: the spark gap and 33K parallel static drain
resistor is between the antenna and ground, not between the antenna and
coax shield/radials. I thought I had photos of all that, but I couldn't
find them today.

Hope this helps.

73, Mike
www.w0btu.com


On Tue, Sep 17, 2013 at 12:43 PM, W2RU - Bud Hippisley <W2RU at frontiernet.net
> wrote:

>
> On Sep 17, 2013, at 1:23 58PM, Mike Waters <mikewate at gmail.com> wrote:
>
> > I've got some more photos and a schematic with capacitor values here, if
> > anyone is interested.
>
> Sure!  I'l like to see what works for your inverted-L.
>
> thanks!
>
> Bud, W2RU
>
>
_________________
Topband Reflector