[Lowfer] New vertical Y antenna

[Bill Ashlock]

Hi Rick,

Yah, the progress has been good because the weather has been above normal lately... and almost no snow. Today, however, is the exception with freezing rain. I'm working inside modifying the one Xmitter I have up here, so it will drive a vertical. I'm starting with a 10 to 4 step-down ratio on the output transformer. That's figuring approx 10 ohm Rac total for the whole antenna (coil + gnd loss). The temporary loading coil I'm using has #18ga (equiv) Litz on it but the final, heavier, one has #12ga (equiv) Litz and wound interwoven for very low loss. 

Looking forward to receiving a return picture of the signal!

Bill

> From: smokinggun at verizon.net
> To: lowfer at mailman.qth.net
> Date: Thu, 15 Dec 2011 02:45:34 +0000
> Subject: Re: [Lowfer] New vertical Y antenna
> 
> Bill,
>  Wow you work fast! Thats a lot of wire to put up in that short time. I 
> cant wait to see the results. I think I still have a capture or 2 from  last 
> season  and my receive setup hasnt changed.
>  Of course once you perfect the new antenna , I will bombard you with 
> questions. Not that Im giving up the loop anytime soon.Its working too well 
> for me right now.
> BTW; thanks for the "Y" formula..
> 
>               Rick
> 
> 
> 
> 
> 
> ----- Original Message ----- 
> From: "Bill Ashlock" <ashlockw at hotmail.com>
> To: <lowfer at mailman.qth.net>
> Sent: Wednesday, December 14, 2011 1:36 AM
> Subject: [Lowfer] New vertical Y antenna
> 
> 
> >
> > Rick and others,
> >
> > I'm all set to begin on-air testing of this new antenna once I install the 
> > loading coil and transmitter at the base and run wires to it. The capacity 
> > measurements between upper and lower "Ys" (plus fill-in wires) are 
> > complete and I'm seeing approx 400pf between them. This makes for a low 
> > Rac in the loading coil because of the relatively low inductance of 185mh 
> > at 185.3KHz.
> >
> > Turned out there was quite a large-sized finge field from the top "Y" and 
> > I had to expand the lower "Y" in order to capture a good percentage of it. 
> > That rule of thumb saying the radius of the ground radials must be at 
> > least equal to the height of the antenna proved to be true, BUT I think 
> > this applies to a vertical WITHOUT top hat. When a top hat is used it 
> > appears the radius must be equal to the antenna height PLUS the radius of 
> > the top hat. At any rate it will be interesting to see how the total Rac 
> > for this antenna comes out when I apply power, but I suspect it will be 
> > very low if I have captured as much of the fringe field as capacity 
> > measurements indicate. BTW there's a formula I found for the capacity 
> > between two circular conductive planes separated by a large distance (like 
> > 50ft) that seems to work. For Lowfer antennas it comes out approx 3 times 
> > the capacity derived from the formula that is typically given in text 
> > books for closely spaced planes not accounting for th
> > e fringe field off to the side. It's a bit lengthy but if anyone is 
> > interested, I'll post it.
> >
> > Bill
> >
> >
> >
> > ______________________________________________________________
> > Lowfer mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/lowfer
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:Lowfer at mailman.qth.net
> >
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: http://www.qsl.net/donate.html
> >
> >
> > -----
> > No virus found in this message.
> > Checked by AVG - www.avg.com
> > Version: 2012.0.1873 / Virus Database: 2108/4678 - Release Date: 12/13/11
> > 
> 
> ______________________________________________________________
> Lowfer mailing list
> Home: http://mailman.qth.net/mailman/listinfo/lowfer
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Lowfer at mailman.qth.net
> 
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html