| Author |
Message |
    
Airplane1
Senior Member
Username: Airplane1
Post Number: 1191
Registered: 5-2004
| | Posted on Tuesday, February 24, 2009 - 11:23 am: | 
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I got this antenna anilizer and it is very nice to use to check my antennas with. I have a question though. If I hook it to my Maco 5/8 and set it for 2 meter band there is some freqs that swr and Ohms match very well. does this mean I can use my Maco on 2 meters in these freqs?
I thought and antenna for 2 meters is small.
Roger |
Hotwire
Senior Member
Username: Hotwire
Post Number: 2744
Registered: 1-2005
| | Posted on Friday, February 27, 2009 - 4:39 pm: |
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I would'nt try running 2 meters on the Maco5/8.
You are correct! A 2 meter antenna is much smaller than one made for 11 meters.
I'm sure there is an explanation for why the MFJ259 is mistaken.
Kenny
CEF491
Reading the mail around Indianapolis Indiana!
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Tech237
Moderator
Username: Tech237
Post Number: 1125
Registered: 4-2004
| | Posted on Saturday, February 28, 2009 - 11:13 am: |
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Firstly 144-148Mhz is exactly 2m but some what close to it. 2M is really 150Mhz.
What you are seeing is the antenna reacting to the 5th harmonic of 11m (again not quite but close allowing for end-effect).A quarter wave at 11M is 102", and at 2m it is 20". Multiply 20 x 5 and we get 100" - again close to an 11M quarter wave. See the pattern forming??
Would I use the Maco on 2m?? ABSOLUTELY NO!!!! The biggest reason is the matching coil used to match a 5/8 wave antenna to coax will do bad things at 2m.
BTW I did once use a 102" whip on 2m using a 1/4 matching stub on the ground side of the coax. Worked well, adn was the antenna I was using the day I worked Aukland NZ on 2m FM from Newcastle Australia - tropospheric ducting.
Simon
Tech237
N7AUS
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Airplane1
Senior Member
Username: Airplane1
Post Number: 1192
Registered: 5-2004
| | Posted on Monday, March 02, 2009 - 1:39 pm: |
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Ok, I think I understand. Thanks |
