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Bluebird
Member
Username: Bluebird
Post Number: 65
Registered: 2-2004
| | Posted on Wednesday, December 26, 2007 - 10:08 am: | 
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First of all i have galaxy 2547 astatic 600 meter & an astroplane.with swr at 1.5 the radio will dead key at 2 watts and swing to 7 watts.
with a swr of 1.9 the radio will dead key at 4 watts and swing to 12 watts,,& at swr 3.0 it will dead key 8 and swing to 18 watts??????????
why the increased power at higher swr levels.
the higher swr levels were at lower freq.
can someone take a few mins to explain....
THANKS
mitchell
bluebird
cef 398
cvc 113
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Bruce
Senior Member
Username: Bruce
Post Number: 4565
Registered: 9-2003
| | Posted on Wednesday, December 26, 2007 - 1:07 pm: |
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no your meter is only good into a 50 ohm load ( 1:1 swr ) otherwise it will give you false readings.
On 6 since 66
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Bluebird
Member
Username: Bluebird
Post Number: 69
Registered: 2-2004
| | Posted on Wednesday, December 26, 2007 - 5:09 pm: |
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thanks bruce,,,that explains everything,,,so i got some tuning to do on my ant,,,thanks again
mitchell
bluebird
cef 398
cvc 113
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Sonny
Intermediate Member
Username: Sonny
Post Number: 174
Registered: 5-2004
| | Posted on Wednesday, December 26, 2007 - 7:15 pm: |
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Mitchell, I would not worry about 1.5 swr your signal will not show any difference on the other stations end to many guys worry about getting a 1.1 |
Marconi
Advanced Member
Username: Marconi
Post Number: 759
Registered: 11-2001
| | Posted on Thursday, December 27, 2007 - 2:54 am: |
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Bluebird the AstroPlane provides no tuning feature. What will you do to tune? |
Bluebird
Member
Username: Bluebird
Post Number: 70
Registered: 2-2004
| | Posted on Thursday, December 27, 2007 - 11:46 am: |
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,,the astroplane has no tuning, when i first installed the ant my swr was sky high,,so i had to shorten the jumper from radio to meter,,after trying a few different lenths i got it down..
mitchell
bluebird
cef 398
cvc 113
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Unit199
Advanced Member
Username: Unit199
Post Number: 579
Registered: 8-2003
| | Posted on Thursday, December 27, 2007 - 9:31 pm: |
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If you shortened coax and it changed your swr, you have an antenna problem, because when you shorten the coax, it should not affect your swr!!!!
HARVE
UNIT199
CEF210
CVC#18
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Captian_radio
Intermediate Member
Username: Captian_radio
Post Number: 301
Registered: 9-2004
| | Posted on Thursday, December 27, 2007 - 10:53 pm: |
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By adding more coax length you probably made a very long dummy load , your coax is acting as a dummy load and absorbing all of your signal due to it having a very high loss factor.Check all the connections and also try making the antenna a bit longer or shorter.
Bob CEF451/VE1CZ
Robert L. Spicer The days of radio are just beginning!
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Vanillagorilla
Senior Member
Username: Vanillagorilla
Post Number: 1082
Registered: 4-2005
| | Posted on Thursday, December 27, 2007 - 11:03 pm: |
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I "think" your on the right track but...what is the SWR reading at the meter? It IS the last thing inline before the antenna right?
If you have good SWR at the meter then the antenna is fine. Your changing of coax length between the radio and meter itself is just changing the way your radio sees reflected power SOMEWHERE.
Sometimes, as Bruce stated SWR meters have a hard time deciphering the reflected and forward power. What you were likely seeing was the true output PLUS the reflected power.
You said you had these readings lower in frequency?
Something to consider is the fact that the radio is tuned with the power band in that freq range?...a little bit of both the above scenario's and you found a possible problem. How LOW did you go in MHz to knock the SWR that far out?
The antenna itself may not be broad banded enough to cover the frequency your trying to use.....in which case an antenna tuner would come in handy  .
Be SURE the coax connectors at the meter are tight and if not already...everything should be grounded well.
AGAIN...if your external meter reads a good match where the antenna was INTENDED to work... then DO NOT touch the antenna.
Good luck~
Hank~CEF559/CEFHAM242
Eastern Long Island NY
KC2RIW
2 OP 905 11m SSB
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Bluebird
Member
Username: Bluebird
Post Number: 71
Registered: 2-2004
| | Posted on Friday, December 28, 2007 - 8:09 am: |
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thanks everyone for the info,,I checked every connector,all good. it is an homebrew ant as you can see in members pics, there might be a wrong lenth in there somewhere..so i got myself an ant tunner and now what ever freq i go on and what ever power I use I can tune it to match.everything is working fine now.........
thanks everyone!!!!!!
mitchell
bluebird
cef 398
cvc 113
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Vanillagorilla
Senior Member
Username: Vanillagorilla
Post Number: 1083
Registered: 4-2005
| | Posted on Friday, December 28, 2007 - 11:10 am: |
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Hank~CEF559/CEFHAM242
Eastern Long Island NY
KC2RIW
2 OP 905 11m SSB
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Tech237
Moderator
Username: Tech237
Post Number: 932
Registered: 4-2004
| | Posted on Friday, December 28, 2007 - 11:19 am: |
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If you shortened coax and it changed your swr, you have an antenna problem, because when you shorten the coax, it should not affect your swr..
Correct BUT it will change the apparent swr by changing the phase difference between power up and power back.. For more details read the article - Coax Cable Myths and Facts
Simon
Tech237
N7AUS
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Bluebird
Member
Username: Bluebird
Post Number: 72
Registered: 2-2004
| | Posted on Friday, December 28, 2007 - 10:53 pm: |
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where can i find that article simon?
mitchell
bluebird
cef 398
cvc 113
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Tech808
Moderator
Username: Tech808
Post Number: 14963
Registered: 8-2002
| | Posted on Friday, December 28, 2007 - 11:33 pm: |
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Bluebird,
Sorry the correct Topic Title is:
Coax Cables – Facts and Fantasy
Written By: Simon ~ Tech237 and can be found in the area of the Copper Forum below.
Copper Talk
» Subscriber (Preview)
» Articles
» Coax Cables – Facts and Fantasy
Or just CLICK HERE > Coax Cables – Facts and Fantasy
Hope this help's,
Lon~Tech808
CEF#808/HAM#001/CVC#002
Tech808@copperelectronics.com
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