On 8/25/2013 6:29 PM, Charlie Cunningham wrote:
Gee, that's really interesting, Andy! I also built a much simpler
oscilloscope when I was a teenager and new ham! Yours was a really elaborate
and impressive 'scope project! Congrats!
Glad to hear from someone who has experience with the KAZ and flag antennas.
My KAZ was for 160 and terminated in 1000 ohms - mostly because that's what
I had on hand. It was a very good RX antenna for 80, 40 and 30m as well.
Your preamp sounds very interesting! It must be fairly elaborate, if it
uses 8 of the J309 FETS! I'd be interested in the circuit!
Best regards,
Charlie, K4OTV
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of Andy Ikin
Sent: Sunday, August 25, 2013 6:32 PM
To: Charlie Cunningham
Cc: Topband Reflector
Subject: Re: Topband: Anyone have a boat load of J-310s?
Charlie,
When I was poor man 40 years ago, I always wanted Tektronix 545B Scope,
which I couldn't afford. So I built a "Chinese Copy" with discarded parts
from the Calibration department of the computer company I worked for. The
scope use many 6DJ8s. I did get it working after about a year; not bad for
some one with no formal electronics training!!!! Tektronix were very helpful
in supplying some critical parts. Looking back I must have been mad, but it
was one hell of away to learn how these things work.!!!!
Bye the way I manufacture a special Head Amplifier for the KAZ and other
Flags. This has 1100 Ohm input matching/isolation transformer, about 20dB
gain and a less than 1dB NF and uses 8 x J309s plus a string of 1N4148
limiting diodes. Wellbrook FLG100LN. There are about 70 units in service
mainly in the US with MW Dxers.
73
Andrew G8LUG
Andrew, i used a antenna similar to the KAZ when I first was on 160,
except I fed it in the middle of the horizontal bottom leg(6 inches
above ground) just like a K9AY, using a 9:1 xfrmr.
It worked like a dream. I used two mounted at right angles just like a
K9AY and rigged it to work in 4 directions like a K9AY, 1000 ohm
termination worked great.
http://www.suddenlink.net/pages/w5uc/160.html#The%20K9AY%20Type%20Array
73,
Mike, W5UC
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Topband Reflector
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