Maria recently wrote:
> Please is there someone out there who can help with some advice for
>a very straight-forward circuit for a matching unit (for high power)
>- in order to use a Vertical Antenna (Minool) on 160/80/40m ?
> Perhaps you can refer me as well to guys building these units?
> Your help will be much appreciated!
>73/88 Maria (zs1afz @ zs1ctc.ctech.ac.za)
I think she must be referring to matching the Battle Creek Special vertical
that went with Chris, ZS8IR to Marion Island. By way of background, the
"Special" is 50 ohms match on 40 & 80 but on 160 the antenna is a 25 ohm
match and we furnish an "unun" 2:1 transformer that is switched in to get
the feedpoint to 50 ohms. Somehow the "unun" was misplaced when stored with
Chris ZS6EZ and we hurriedly sent another directly to Maria but it arrived
too late to make the departure of ZS8IR off to Marion. And it must be a
problem getting the unun to him now - ie the reason for Maria's question, I
Guess we're not sure what is available on Marion but Chris, ZS6EZ thot they
could conjure up something. If coils and variable capacitors are available,
a simple "L" network would suffice. If just capacitors, an omega match with
series and shunt capacitor will work. It may be that the transceiver and
the Amp will stand the 2:1 match themselves.>
73/88 George W8UVZ