Re: Topband: Beverage Length vs F/B or (RDF?)

2019-10-19 Thread Ed Sawyer
I can't speak to switchable bi-directional arrays but I can speak to my 900ft terminated beverage (450 Ohm resistor to a ground rod with 2 - 1 / 4 wave radials per band). It has 20db plus front to back ratio on 40 - 160M. The gain is sometime not much more than half an S unit to one S unit vs my

Re: Topband: Beverage Length vs F/B or (RDF?)

2019-10-18 Thread donovanf
ank W3LPL - Original Message - From: "MU 4CX250B" <4cx2...@miamioh.edu> To: "Artek Manuals" Cc: topband@contesting.com Sent: Friday, October 18, 2019 2:51:50 PM Subject: Re: Topband: Beverage Length vs F/B or (RDF?) Thanks for the suggestion, Da

Re: Topband: Beverage Length vs F/B or (RDF?)

2019-10-18 Thread Artek Manuals
Jim When you say it measured 70K was that DC, low frequency (60hz) A/C or at 1.8/3.5 Mhz RF? Big difference. ' Here two 5' rods about 2' apart measure about 2K DC but measure about 600 ohms at 1.8 Mhz...Still not sure how that correlates to a larger earth RF ground. The other thing is RF

Re: Topband: Beverage Length vs F/B or (RDF?)

2019-10-18 Thread MU 4CX250B
Thanks for the suggestion, Dave. I’m using DXE hardware and relay boxes for switching, and twin lengths of WD-1A mil surplus telephone cable for the wires. The lengths are spaced roughly 6 inches apart to approximate 450 ohms. The end terminations are three 8ft ground rods spaced out about 4 ft

Topband: Beverage Length vs F/B or (RDF?)

2019-10-18 Thread Artek Manuals
Jim Poor front to back can indeed be a result of being too long. Although w8JI would argue that at 700 feet your just about at optimum (1.5 wavelengths)  I would think it would be easy to add an insulator /jumper and a set of terminations and  grounds at ~500 feet and see what the difference

Re: Topband: Beverage length

2019-08-01 Thread Joe
Thanks Drew, I thought for some reason it was behaving like a dipole. At short lengths more boradside to the antenna and as it gets longer the lobe gets smaller and more pointing towards the end of the wire. Now, a BOG. if you do NOT terminate it, does it behave like a Rohmbic where it's Bi

Re: Topband: Beverage length

2019-08-01 Thread Chortek, Robert L.
osoft.com/fwlink/?LinkId=550986> for Windows 10 From: Chortek, Robert L.<mailto:robert.chor...@berliner.com> Sent: Thursday, August 1, 2019 2:40 PM To: Drew Vonada-Smith<mailto:d...@whisperingwoods.org> Cc: topband@contesting.com<mailto:topband@contesting.com> Subject: Re: Topb

Re: Topband: Beverage length

2019-08-01 Thread Chuck Dietz
, Robert L. Sent: Thursday, August 1, 2019 2:40 PM To: Drew Vonada-Smith Cc: topband@contesting.com Subject: Re: Topband: Beverage length I’ve got an unterminated 300’ foot beverage about 36” high. WorkS GREAT so I respectfully disagree with the implication a beverage much shorter than 1-2

Re: Topband: Beverage length

2019-08-01 Thread Chortek, Robert L.
I’ve got an unterminated 300’ foot beverage about 36” high. WorkS GREAT so I respectfully disagree with the implication a beverage much shorter than 1-2 wavelengths means you should use something else. I’ve got multiple rx antennas and that short beverage is the best one,on average, in its

Re: Topband: Beverage length

2019-08-01 Thread Drew Vonada-Smith
Joe, For a simple Beverage, you just point the antenna (unfed end) at the target. For length, "longer is better" is approximately true, but the ideal lengths are about 1 to 2 wavelengths. Much longer than that, and phased shorter Beverages work better. Much shorter than that, and you might

Topband: Beverage length

2015-09-25 Thread LY2KZ
Hi guys, I'm contemplating to build beverage pointing to W6-W7-VE7 for this season. If everything goes well I will not be limited in its length. Therefore question: what is best length to use? I have read some material on the web and still not sure how velocity factor will impact beverage