Need help calibrating my SWRs

Help with installing an Antenna, or just choosing the right antenna to go with your radio, or your mobile.

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Need help calibrating my SWRs

Post by MikeM86 » Monday, 04 September 2017, 12:54 PM

Hello all,

I'm new to this forum, and need help calibrating the SWRs on my antenna. Here's my set up.

Midland 75-822 handhelp radio
K30 mobile antenna

The antenna is mounted on my trunk lid. I can not mount it on the roof because I have a sunroof, and when open there isn't enough room for the base.

I'm trying to set the SWRs and have the following issue. On channel 1, the SWR is 1.3 and on channel 40 it's 3.25-ish. With the whip in it's lower most point. I haven't tried to shorten the antenna yet, because I haven't figured out how to shorten the length. The whip is to tough for normal wire cutters.

Would using a 4 inch spring help?

All suggestions are welcome.


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Re: Need help calibrating my SWRs

Post by MDYoungblood » Monday, 04 September 2017, 16:28 PM

Hello MikeM86,
Welcome to the forum. Looking at what you wrote the antenna in too long so forget the spring. With a K30 start checking the SWR when the antenna whip is bottomed out in the base or load is what it is called. now checking the SWR should be done in a clear area free of any metals that may react with the checking process, doors shut, etc. With that antenna don't look for a perfect match, try to get the center of the band as low as possible and then balance out the ends of the band so they are reading the same. Any more advice just ask.
As a new member to the forum could you post a intro in the "Welcome to the Forum" topic, viewforum.php?f=89 , so others on the forum can say "Hi", thanks.



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Re: Need help calibrating my SWRs

Post by dgbacb4148 » Monday, 04 September 2017, 19:57 PM

:bounce: Mike, welcome to CBRT FROM Georgia Dawg country, glad to have you.
David g......... :cheers:

AKA Southwind,Tripple Nickel, DX 555. Base station Uniden Washington Philippines made/ D-104 Tug 9/ Silver Streak 150/ Pyramid Gold Series Variable 26 amp through "Old Reliable Shakespeare Big Stick"... Mobile- Cobra 25, NMO Firestik.

USAF 1959-1963/ Andrews AFB, 1001st Transportation Squadron, Maryland, home of AIR FORCE ONE. John F. Kennedy Presidential Innaguration parade 1961

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