| Author |
Message |
    
Wildrat
Senior Member
Username: Wildrat
Post Number: 1226
Registered: 12-2003
| | Posted on Saturday, February 24, 2007 - 9:34 am: | 
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Man, this area is getting large, nearly takes a minute to load.
Anyway, Will clear poly affect the electrical properties of a beam?
WILDRAT
MARK
27.285MHZ
CEF674
CVC029
|
Tech237
Moderator
Username: Tech237
Post Number: 706
Registered: 4-2004
| | Posted on Sunday, February 25, 2007 - 9:13 am: |
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The answer is yes/no/maybe. It all depends on the poly. Poly made for different applications have different chemical components, one of which is carbon. The amount of carbon can effect antennas.
In the past, yopu may have noticed that in several posts I have advised to stay away from black or dark coloured PCV pipe when enclosing antennas. The reason being these have a larger amount of carbon than some of the other colours and I found out from experience, that if you run any power over about 150w they also melt.
What you can try is to get small pieces of the poly you want to use, place it and a dish of water in the microwave (preferably when the XYL is not home) and run it on High for a couple of mintues. If the poly is anything other than slightly warm it is suspect.
Wish I still had photos of the colinear we built for 440MHz that used black PCV as insulators. 5 minutes at 200w and it was anything but straight.
Oh yes, lower frequecnies may have less problems than the higher ones.
Hope this helps you a little.
Simon
Tech237
KD7IEB
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Wildrat
Senior Member
Username: Wildrat
Post Number: 1231
Registered: 12-2003
| | Posted on Sunday, February 25, 2007 - 8:38 pm: |
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Thanks Simon! I will do the Beaker Science project tomorrow. I was given a Maco 4 element and it has some light oxidation. I was going to sand it and thought about spraying it with the poly to slow down the oxidation. What would you do?
WILDRAT
MARK
27.285MHZ
CEF674
CVC029
|
Tech237
Moderator
Username: Tech237
Post Number: 709
Registered: 4-2004
| | Posted on Monday, February 26, 2007 - 9:07 am: |
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ON an 11m antenna poly in most forms should not be a problem - go for it.
Simon
Tech237
KD7IEB
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Wildrat
Senior Member
Username: Wildrat
Post Number: 1234
Registered: 12-2003
| | Posted on Monday, February 26, 2007 - 1:34 pm: |
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Thanks Simon!
I also put a ? in the Coax area , if you could enlighten me.
WILDRAT
MARK
27.285MHZ
CEF674
CVC029
|
