On 12/25/2010 4:26 PM, Wm. Freddy Curtis wrote:
> I would like to construct my first beverage antenna for 160 m and 80 meters.
> I first thought about using 300 ohm twin lead - I have about 400 feet
> (having read ON4UN's book 300 feet will be the cone-of-silence so would make
> it that). I also had Bruce Clark - K1FZ construct a KB-2 and KB-3 (300-450
> ohms) transformers. However, I recently found a partial spool ( 576 feet)
> of Belden M - Mediatwist 1872A Cat 6 cable 4 Pair Unshielded each 23 awg.
> Looking at the Belden website it states this cable is 100 ohm +-12 input and
> 100 ohm +-15 output.
>
>
>
> My question is this: Can I use this cable if I combine the wires? Example
> tie the blue and blue/white with the orange/orange/white - for the first
> terminal on the KB-2&3. Then combine brown and brown/white with the green
> and green/white - second terminal on the KB-2&3. Again by combining the
> wires together will it then be around 400 ohms?? Would it work with the KB-2
> & KB-3 at 300 to 450 ohms??
>
>
>
> This is my first beverage, and I believe the difference between 300 ft and
> 576 ft would be substantial in performance. Would like also to know if
> anyone else has used this type of cable for a beverage. Thanks to all for
> replies! Merry Christmas and Happy New Year 2011.
>
>
>
> 73's,
>
> Freddy Curtis - KC4GUG
>
Freddy,
if you tie them together like you describe you will end up with a lower
impedance then by floating the unused pairs...or a better solution is to
tie them all together and make it a single wire
Beverage. My experience with CAT 5 cable, unless it is the flooded
outdoor variety is that it will not last long exposed to sun, rain, and
wind. The WD-1A is much tougher and even that need to be checked
often. Cheaper is 300 ohm twinlead for 2 wire Beverages as long as you
have numerous supports. Some TB specialist recommend you twist it to
further reduce ground influences and pattern distortion or both.
Regards,
Herb Schoenbohm, KV4FZ
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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