Topband: New 160M high performance receiving antenna at W3LPL

[donovanf at starpower.net]

Hi Larry,

There isn't much difference between 70 foot and 130 foot end-fire spacing.  If there isn't any other consideration, 130 feet is probably the better choice.

73
Frank
W3LPL


---- Original message ----
>Date: Sat, 2 Feb 2013 19:13:22 -0500
>From: "Larry - K1UO" <k1uo at uninet.net>  
>Subject: Re: Topband: New 160M high performance receiving antenna at W3LPL  
>To: <donovanf at starpower.net>
>
>Thanks for the tips Frank...This Spring Ill try the 300ft spacing...Also do 
>you think I should go to 130ft endfire spacings rather than 70?
>
>I have the space because I have great rural neighbors!   quiet ones also.
>
>73
>
>
>
>
>-----Original Message----- 
>From: donovanf at starpower.net
>Sent: Saturday, February 02, 2013 2:57 PM
>To: topband at contesting.com
>Cc: Larry - K1UO
>Subject: RE: Topband: New 160M high performance receiving antenna at W3LPL
>
>Hi Larry,
>
>Your 160 meter CW skimmer is working extremely well, it spotted T6LG last 
>night.  No other U.S. skimmer spotted him!  I couldn't hear any trace of 
>T6LG, I guess I need to move my BSEF receiving array to Maine!
>
>I use exactly the implementation described at:
>
>http://pvrc.org/bsef/bsef.html
>
>Each vertical is 25 feet of aluminum tubing with four 25 foot umbrella wires 
>and eight 70 foot radials (inexpensive 16 AWG speaker wire) laid on the 
>ground.  The verticals are low impedance at the base, so there are 
>absolutely no issues with handling very high impedances like in the Hi-Z 
>array.  My insulators are phenolic, but any insulator -- even wood -- will 
>work fine with low-Z verticals.
>
>The strong advantage of the low-z BSEF array is that there is no need to 
>adjust the phasing, the only adjustments are is inductors and resistors at 
>the base of each vertical.  Adjusting them takes five minutes or less.  If 
>you want to steer the sidelobes, you could eliminate the fixed phasing line 
>in the center of the array and run two RG-6 feedlines to a DX Engineering 
>NCC-1 Receive Antenna Variable Phasing Controller in your shack.
>
>The low-Z BSEF receiving array has important disadvantages too:
>  - it is physically large (300 x 130 ft),
>  - it needs radials, and
>  - its strictly a monoband antenna.
>
>Each vertical is base loaded with a resistor and inductor, adjusted to 
>resonance (75 + x0) at 1840 kHz.  Each base loading enclosure has a BNC 
>connector that I use only with my MFJ-259 to set the impedance to exactly 50 
>ohms resistive and zero ohms reactive at 1840 kHz.  A 25 ohm resistor 
>(measured with a digital ohm meter) runs from the BNC connector to the 75 
>ohm F-connector.  The RG-6 must be disconnected when connecting the MFJ-259 
>to the BNC connector.
>
>The F-connector connects to a half wavelength (225 feet) of RG-6 that goes 
>to the RF combiner near the center of the array.
>
>The RF combiner uses three Minicircuits Labs 75 ohm splitters used as simple 
>RF combiners.  The only phasing line is a 68 foot length of RG-6 and a phase 
>inversion transformer that sets the relative phase of the rear two broadside 
>verticals relative to the front two broadside verticals.  This phasing 
>provides minimum sidelobe levels.
>
>I highly recommend the low-Z BSEF array since you obviously have the space. 
>You should reduce your broadside spacing to 300 feet rather than 320 feet, 
>your sidelobes will be minimized as a result.  Although 320 feet is a good 
>choice for a transmitting BSEF array (maximum gain), 300 feet is a better 
>choice for a receiving BSEF array (minimum sidelobes).
>
>I'll be pleased to answer any specific questions about my BSEF receiving 
>array implementation.  The three photos pretty well cover everything I could 
>possibly tell you.
>
>73
>Frank
>W3LPL
>
>
>
>
>
>---- Original message ----
>>Date: Sat, 2 Feb 2013 10:51:52 -0500
>>From: "Larry - K1UO" <k1uo at uninet.net>
>>Subject: BSEF
>>To: <donovanf at starpower.net>
>>
>>   Hi Frank,
>>
>>     I read with interest your comments on the new BSEF array
>>   there.   My experiments with a 70X320 BS/EF array with 20ft
>>   Hi-Z type verticals was short lived since strong winds toppled
>>   trees directly on top of 2 of the verticals!!  The direction I
>>   am aimed is favoring Africa one way and the North Pacific the
>>   other (switchable).
>>   I will be rebuilding them to 24ft verticals with fiberglass
>>   rod insulated bases (less pf) and trying it once againSmile
>>   Initial results were comparable to a small broadside phased
>>   Beverage array here but that was without any tweaking of the
>>   phasing and of course directions were not exactly the same.
>>   What phasing arrangement did you employ?
>>
>>   73 and congratulations
>>
>>   Larry  K1UO 
>
>