test
>From M Glenn Vinson Jr <mgvinson@crl.com> Thu Sep 29 16:50:22 1994
From: M Glenn Vinson Jr <mgvinson@crl.com> (M Glenn Vinson Jr)
Subject: RTTY from 8R1TT
Message-ID: <Pine.3.87.9409290822.A14636-0100000@crl.crl.com>
G0AZT, Eddie, and W6OTC, Glenn, will travel to Guyana on October 13, 1994
to activate RTTY as 8R1TT. They will participate in the JARTS WW RTTY
Contest (Oct. 15-16) and will be active 80-10 meters before and during the
contest. After the test, Eddie will operate from Laguan Island (SA-068)
in the Essequibo River until October 20. QSL all contacts with 8R1TT to
Eddie Schneider, POB 5194, Richmond, CA 94805.
>From W. M Wood - The Signal Group" <mikewood@mercury.interpath.net Thu Sep 29
>21:28:49 1994
From: W. M Wood - The Signal Group" <mikewood@mercury.interpath.net (W. M Wood
- The Signal Group)
Subject: Beverage antenna impedance
Message-ID: <199409292028.QAA23330@mercury.interpath.net>
Bill,
Buy an old HP250B RX Meter. It's basically the same as a General
Radio RF impedance bridge (GR916 or 1016) except that it has
the rf oscillator (.5-250 MHz) and detector built in. Weighs
about 50 lbs though. But you can read the Resistance and the reactance.
I have 3 of them and a GR916. A Boonton 250 is the same as an Hp 250.
Other less accurate , but useful , methods.
1) Build or buy a 9:1 balun. Then measure the impedance through
the balun using an MFJ 259 or a Palomar noise bridge. Multiply
the resulds by 9.
2)Use a $900 HP vector voltmeter and a calibrated output signal
generator (like the old HP606 etc) to measure the impedance.
3) Put a carbon type (non-reactive) variable resistor in place
as the terminting resisance on the beverage. Tune the resistance
for maximum rejection of a signal arriving off the rear off
the beverage (best front to back ratio) . This can be a very sharp
adjustment. Use about a 1 or 2 k pot. Then remove
the pot and measure the resistance of the pot (between the wiper and
the end that was connected to the beverage). That will be close to the
impedance of the antenna. Use a DVM to measure the resistance.
See you in the pileups Bill. I'll be one of the last stations
making it through , but I usually make it.
73, Mike
Mike Wood Internet: mikewood@mercury.interpath.net
The Signal Group Amateur Radio: NT4O
P.O. Box 1979 ***Avoid company disclaimers by owning the company ***
Wake Forest, NC 27588
Phone: 919-556-8477 Fax: 919-556-0115
>From tomrune@mac_inge.itek.norut.no (Tom Rune Lauknes) Thu Sep 29 23:09:10
>1994
From: tomrune@mac_inge.itek.norut.no (Tom Rune Lauknes) (Tom Rune Lauknes)
Subject: No subject
Message-ID: <9409292109.AA00410@mac_inge.itek.norut.no>
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