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Splbass17
Junior Member
Username: Splbass17

Post Number: 46
Registered: 9-2005


Posted on Tuesday, April 10, 2007 - 4:53 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Using the built in SWR meter while tuning antenna:
I get 2 bars dead keying on channel 1
I get 1 bars dead keying on channel 20
I get 2 bars dead keying on channel 40

You can look at it both ways from channel 40 or channel 1,so I picked channel 1 and the rule is if the SWR is high on 1 then raise the antenna, so I raise it and I get one bar but then my channel 40 gets 3 bars.

Now if I lower it to compensate for CH.40 it brings me right back to the same situation. Am I getting it as good as it can get?
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Romstar
Member
Username: Romstar

Post Number: 81
Registered: 3-2007


Posted on Tuesday, April 10, 2007 - 5:33 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

It's pretty close. The only other thing you can do is to cut some of the whip down and see if that changes the reading.

I don't advise anything this drastic until you have a good SWR meter, and you have tried all other options.

You can always shorten an antenna, but you will have a hard time lengthening it.

Romstar
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Dale
Advanced Member
Username: Dale

Post Number: 746
Registered: 12-2002
Posted on Tuesday, April 10, 2007 - 7:18 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

thats assuming the built in meter is half way desebnt.mine had basically same reading but when put on a swr meter i had a 1.5 on ch.1and 2.1on 40.also turn dk.all way down when doing swr seems more accurate
dale/a.k.a.hotrod
cef426
cvc#64
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Splbass17
Junior Member
Username: Splbass17

Post Number: 47
Registered: 9-2005


Posted on Tuesday, April 10, 2007 - 9:47 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

WOW, sounds like the built in meter stinks! Ok I'll definitly try turning the Dead Key down, I never thought of that thanks. And yes I do agree I would be pretty complicated to lengthen my whip haha
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2ir473
Intermediate Member
Username: 2ir473

Post Number: 113
Registered: 7-2002
Posted on Wednesday, April 11, 2007 - 8:02 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

The built in SWR meter isn't that sensitive, but gives you a quick indication of your match.
The initial readings you posted (1 bar on ch 20, 2 on 1 and 40) would indicate you are at least tuned for the center of CB band.
When taking your measurements, be parked away from buildings and have your doors closed.
Also, from your photo in the other section, I think you are using a magmount antenna. Magmount antennas are fine, but there is a compromise with a magmount antenna, and that may affect your SWR readings. You may want to remove the antenna from the roof occasionally and clean the roof area thoroughly. Dirt and road salt can get under the magnet and degrade performance.

There is an excellent website of an amateur operator that describes mobile installations, including antenna mounts, bonding (grounding-check this part out especially-excellent info that has reduced my mobile noise considerably), electrical systems, etc. It applies not only to ham radio, but CB radio as well. Worth taking a lot through the site.
www.k0bg.com
Paul
2IR473
CEF-218
CDX8412
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Dale
Advanced Member
Username: Dale

Post Number: 755
Registered: 12-2002
Posted on Wednesday, April 11, 2007 - 8:27 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

thanks for the site paul.i wanna check that out myself.spybas i had a 2970 with same antenna
i had 2 bars on ch.x
and had 3 bars on ch.x
i put a mfj swr meter on thier it was a 1.4-1.7
ouch way too high i ended up trimming my stinger
up about 1/2 inch then had 1.1-1.2.but its not
always that way some installs require raising the whip.heres my way of doing it
this is usually what i see
higher on ch.40 shorten/trim stinger
havent seen this senario much but
higher on ch.1 raise whip out of holder.if this
is your case wilson does make a longer stinger
however im not sure if coppers carry it
dale/a.k.a.hotrod
cef426
cvc#64
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Splbass17
Member
Username: Splbass17

Post Number: 55
Registered: 9-2005


Posted on Friday, April 13, 2007 - 1:59 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks !

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