OT Hypothetical KAT500 antenna connection question

[Frederick Atchley]

I have a question about connecting the KAT500 (outside version) to an 80
thru 10 meters wire antenna.

As an example, I have a "Mystery" antenna which, like the G5RV uses a tuned
length of twin-lead as part of the antenna design. Therefore I will have two
possible places to couple the KAT500 to the old antenna:

a. At the present input end of the twin-lead.
b. At the antenna center point (do away with the twin-lead.)

Another alternative would be to replace the old antenna with a new wire. I
believe this alternative would require selecting a longest length of wire
which avoids a quarter-wave length multiple on any band. Any ideas on what
length that would be?

Since getting the KPA500, I have added tuned antennas on 10, 15 and 40. On
those three bands, I can use the amp w/o a tuner. I'm leaning toward a new
wire to replace the "Mystery" antenna for 80 and 20 meters.

Last week at 0500Z, I worked Cape Town, South Africa on 20 meters with 200
watts (KPA500 sometimes blinking red.) So, now is the time to prepare. I
welcome your thoughts and I assure you that I have great respect for your
input.

73, Fred, AE6IC, K-Line

 

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[Fred Townsend]

Fred:
Your option 'b' is not an option. As you acknowledge the twin lead is a
tuning device. Remove the twin lead and you need a lot more antenna tuner.
The twin lead is not a perfect tuner so it is advisable to cascade an
adjustable antenna tuner as well. If you want tuned antennas the dimensions
for dipoles are readily found. Be advised your 80 meter dipole will be
longer than a G5RV.
73
Fred, AE6QL

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of Fred Atchley
Sent: Monday, October 24, 2011 10:45 AM
To: [hidden email]
Subject: [Elecraft] OT Hypothetical KAT500 antenna connection question

I have a question about connecting the KAT500 (outside version) to an 80
thru 10 meters wire antenna.

As an example, I have a "Mystery" antenna which, like the G5RV uses a tuned
length of twin-lead as part of the antenna design. Therefore I will have two
possible places to couple the KAT500 to the old antenna:

a. At the present input end of the twin-lead.
b. At the antenna center point (do away with the twin-lead.)

Another alternative would be to replace the old antenna with a new wire. I
believe this alternative would require selecting a longest length of wire
which avoids a quarter-wave length multiple on any band. Any ideas on what
length that would be?

Since getting the KPA500, I have added tuned antennas on 10, 15 and 40. On
those three bands, I can use the amp w/o a tuner. I'm leaning toward a new
wire to replace the "Mystery" antenna for 80 and 20 meters.

Last week at 0500Z, I worked Cape Town, South Africa on 20 meters with 200
watts (KPA500 sometimes blinking red.) So, now is the time to prepare. I
welcome your thoughts and I assure you that I have great respect for your
input.

73, Fred, AE6IC, K-Line

 

______________________________________________________________
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Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

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Please help support this email list: http://www.qsl.net/donate.html

______________________________________________________________
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Help: http://mailman.qth.net/mmfaq.htm
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