Topband: 160 vertical/L

[Alan Swinger]

As an example with excellent performance, I use and recommend a COAX Inverted-L with elevated 100 ft radials (I use 7, but 4 will work). Since the 65 ft vertical Coax shield is not connected at the top where center conductor connects to the horizontal wirw (or sloped in my case), no matching system is needed at the base - it is a resonant ant . . . and will also perform well on 80 by moving the Grd connection from below the Line Isolator (connects the feed line to the Vertical Coax) to above it. Tuning stubs on the wire portion take care of where in the bands you want resonance.

I adapted Scott Harwood's (K4VWK) design published in the Mar 2012 QST - go there for details. If you can deal with 4-6 Elevated radials, this beats the heck out of buries or on grd 30+ radials.
Alan - K9MBQ


-----Original Message-----
>From: donovanf at starpower.net
>Sent: Nov 30, 2016 5:16 AM
>To: topband <topband at contesting.com>
>Subject: Re: Topband: 160 vertical/L
>
>Hi Mike, 
>
>
>An inverted-L with 50-60 feet vertical is a far superior choice than 
>a bottom loaded vertical. Its much more efficient, its bandwidth 
>is much broader and you don't have to deal with the very high 
>voltages at the base of the loaded vertical, especially if you're 
>running high power. 
>
>
>73 
>Frank 
>W3LPL 
>
>
>
>----- Original Message -----
>
>From: "Don Kirk" <wd8dsb at gmail.com> 
>To: "W0MU Mike Fatchett" <w0mu at w0mu.com> 
>Cc: "topband" <topband at contesting.com> 
>Sent: Wednesday, November 30, 2016 12:32:26 PM 
>Subject: Re: Topband: 160 vertical/L 
>
>HI Mike, 
>
>I use a 68 foot based loaded vertical on 160 meters with 55 short buried 
>ground radials (2500 feet of ground radials). I only run 100 watts and 
>located near Indianapolis. I would prefer an Inverted-L over the base 
>loaded vertical on 160 meters (the L would be much more efficient), but 
>having said that I did acquire my 160 meter DXCC last year (all CW) and 
>most of the contacts were during years when 160 meters was in very poor 
>condition. 
>Note: I do use small pennant antennas for RX on 160 meters. 
>
>For starters it sure would be easy to temporarily install a base loading 
>coil to test out your full size 80 meter vertical on 160 meters versus your 
>33 foot vertical. You can use part of the loading coil you install on the 
>full size 80 meter vertical with a fixed high voltage silver mica cap to 
>form a simple L network (that's what I do and it works great). This would 
>allow you to easily compare your two TX antennas. 
>Note: neither end of my base loading coil is connected to ground (my base 
>loading coil is between the bottom of my 68 foot vertical and the center 
>conductor of my feedline. I use an MFJ 404-0669 air wound coil as my 
>loading coil / L network. 
>
>But if you can install an Inverted-L easily, than I would skip what I have 
>said above and just install the Inverted-L. 
>
>Don (wd8dsb) 
>
>On Wed, Nov 30, 2016 at 1:33 AM, W0MU Mike Fatchett <w0mu at w0mu.com> wrote: 
>
>> I have a full sized 80m vertical and a Top loaded Cushcraft 33ft vertical 
>> for 160. The Cushcraft gets out but not great. 
>> 
>> I was thinking about using an inverted L over the radial field that I use 
>> for the 160. It is 30ish radials of various lengths or I have seen where 
>> people have loaded the 80m vertical on 160. I think I recall people are 
>> not overly excited about bottom loading the 80. The 80 is unguyed so the 
>> top cannot support anything. 
>> 
>> I can get the vertical part of the L up 50-60 feet. 
>> 
>> Any feelings one way or another? I can make a switching system for the 80 
>> vert if people think this is a reasonable transmitting solution. I have a 
>> rcv array, so I am hoping to improve my xmit signal. 
>> 
>> W0MU 
>> 
>> _________________ 
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>> 
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