| Author |
Message |
    
Cm3885
Intermediate Member
Username: Cm3885
Post Number: 334
Registered: 12-2003
| | Posted on Saturday, April 10, 2004 - 11:38 pm: | 
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I replaced the wire on the backside of the beam (the reflector wires) from the #14 guage bare copper wire to using #14 guage UV black plastic coated wire. Will this work ok or do i need to go back to using the bare wire? Ive heard a few guys that have used coated wire because it holds up better in ice and bad weather condtions.... |
Dindin
Member
Username: Dindin
Post Number: 55
Registered: 2-2004
| | Posted on Sunday, April 11, 2004 - 12:27 am: |
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Cm3885,As long as you got the dimensions correct the insulated wire will work just as well as the bare.wind load will be slightly higher but not enough to worry about.rf energy on the antenna will not"see" the insulation. |
Bruce
Senior Member
Username: Bruce
Post Number: 1139
Registered: 9-2003
| | Posted on Sunday, April 11, 2004 - 8:44 am: |
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JUST MY OPINION
The use of more than one wire on a quad reflector is a wast of time ..... it will not matter if you use insulated or not..
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Dindin
Member
Username: Dindin
Post Number: 56
Registered: 2-2004
| | Posted on Sunday, April 11, 2004 - 11:33 am: |
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Bruce,I,ve always been under the impression adding more wires to a MR4 or similar antenna was a mistake(i.e.Rejection Kit).each loop of wire being smaller than the original reflector would start acting as a director would start increasing gain on the backside,in otherwords cancelling out rejection.just the way I see it. |
Tech833
Moderator
Username: Tech833
Post Number: 629
Registered: 8-2002
| | Posted on Sunday, April 11, 2004 - 2:26 pm: |
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Dindin, you are correct. Multiple wires the same size as the original reflector will help slightly though (keep them an inch or two apart). That means mounting spreaders on the ends of the reflector support elements. A long time ago, a two element quad was made that had two reflector wires on it. They were spaced 3 inches apart.
Substituting coated wire for the original bare wire will change things a bit, but not enough to worry about. The coated wire will look 'longer' to RF than the bare wire will. |
Bruce
Senior Member
Username: Bruce
Post Number: 1141
Registered: 9-2003
| | Posted on Sunday, April 11, 2004 - 1:23 pm: |
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dindin
im with you it makes no sence |
Cm3885
Intermediate Member
Username: Cm3885
Post Number: 337
Registered: 12-2003
| | Posted on Sunday, April 11, 2004 - 7:18 pm: |
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What do you mean it will look longer to RF? Will that mean my SWRs will go up?
I guess i should have went with the regular non coated wires. I kinda had a feeling that the coating would do something... |
Dindin
Member
Username: Dindin
Post Number: 58
Registered: 2-2004
| | Posted on Sunday, April 11, 2004 - 9:42 pm: |
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Cm3885,you did ok.the wire lengh would be slightly different taking velocity factor into account.without sophisticated range gear you wont see a measureable difference with the wire you used.there is probley a greater difference in lengh between a hot day and a cool night! |
Cm3885
Intermediate Member
Username: Cm3885
Post Number: 339
Registered: 12-2003
| | Posted on Monday, April 12, 2004 - 12:16 am: |
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Oh ok... LOL.
Now that wire deal were you add wires to the backside ive done that once before... It work OK but i wasnt sold on it... I had a PDL 2 that had them like that.. I sold it for the rakers i have now...... |
Bullet
Intermediate Member
Username: Bullet
Post Number: 308
Registered: 7-2003
| | Posted on Wednesday, April 14, 2004 - 6:24 pm: |
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rejection kits were they use mulitple wires on the reflector, each one smaller in size, will look like directors to the beam and increase back lobe.
try it yourself with a feild strength meter and take readings 360 deg around the beam.
multiple wire elements like 833 mentioned do work to some degree but not alot of change to make it worth while.
do a before and after and youll see how they change the pattern of the beam.
screens do work, and work well if you want to go to that amount of trouble. |
Tech808
Moderator
Username: Tech808
Post Number: 2143
Registered: 8-2002
| | Posted on Wednesday, April 14, 2004 - 11:42 pm: |
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Dindin,
Maybe this is what you are looking for:
CLICK on the LINK Below,
http://www.copperelectronics.com/cgi-bin/checkitout/checkitout.cgi?catalogSTORE:CKIE:prod010-00040+
Hope this help's.
Lon
Tech808 |
Cm3885
Intermediate Member
Username: Cm3885
Post Number: 351
Registered: 12-2003
| | Posted on Saturday, April 17, 2004 - 7:49 pm: |
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Today I changed the wire back to regular bare copper wire. I dint want to take any chances of the coated wire not working right.. Ive done this before but man, its a pain stretching the wire and marking it and then making sure the dimenshions are correct but ive got it all down to a T now! Im sure it will work good now. |
