Hi Gang
A few have asked about the ZX0F phased bevs - this is the N2RM design and
appears on the W3LPL hotlink on the contesting.com website.
Http://www.contesting.com once on the home page, link to the "W3LPL on
Beverages" page for more info.
Briefly
1) You run out side by side 580 foot wires
2) Space them 200 feet apart - maintain spacing as best you can for all 580
feet
3) They are not staggered - truly parallel to each other the whole length
4) Run equal RG58 feedlines from each 9/1 matching transformer (we used 110
feet just to be safe) into a TEE connector - the tee connector winds up
equidistant between the feedpoints of the two side by side wires
5) Plug the TEE connector into an AMIDON UNUN 50/25 ohms matching unit or
equivalent. (This takes the 25 ohms impedance present from the teed up
antennas (25 ohms in parallel) and converts it to 50 ohms on the other side
which will match the 50 impedance now of the feeder line - also Rg 58 in our
case.
While you may make up 1/4 wave RG11 (70 ohm) phasing lines to handle the
impedance transformation, this is alot of coax - AND - it limits the
usefulness of such a system to a single band.
The UNUN is a broadbanded device and will allow the use of such a beverage on
160/80/40 with no deterioration in performance. We used these bevs on both
80 and 160M by means of a K1FZ splitter. Bruce makes a GREAT splitter and I
highly recommend it - he made up three custom made units for me for ZX0F and
they performed superbly!
You plug the feedline into your beverage box.
ach beverage was terminated with a 470 ohm resistor to ground (10 radio
Shack 4700 resisitors 1/2 watt) connected together in parallel.
The feedpoint 9/1 boxes were ICE 251's available from Radioware - 1 800 950
WARE or via NX1G@top.monad.net
NX1G is Craig Clark at Radioware - proprietor and a GOOD GUY!
Craig has handled the shipping of all my stuff over to A61AJ and has made
this part of the trip relatively easy - all the stuff I need for Topband will
be waiting there when I arrive this time. Such a deal.
Trust this is clear on th BEVS.
What the phasing does is:
Add about 3DBi additional gain to the system when compared to a single wire.
IT also sharpens the side rejection of the system. I can attest to this as
when listening to EU we could NOT hear the USA and vice versa.
73 JEFF
K1ZM@aol.com
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