[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

Re: Cheap Yagi



They work fine if you are reasonably careful with dimensions.  Certainly 
they qualify for best dBs/$$..

At 902 and above a lathe helps to cut accurate lengths for the elements.

At 435 and down I use a diamond cutting wheel on a Dremel that works 
wonderfully.

I find a cordless drill works best for the boom, even better than a press.. 
if you get a hole that isn't square, just bend the elements to straighten 
them up on the axis.  I also recommend the 1/8" push nuts to hold the 
elements.  They are hard to get but are available from McMaster-Carr.

The 435 I built worked with no adjustments.  I haven't yet built the other 
polarity on the boom and/or circularized it.  (And won't for sometime)

A friend of mine built his on square tube fiberglass from MaxGain systems 
http://www.mgs4u.com-- and they look really nice.. so that is
a possibility as well.

I noticed that I do not have the satellite dimensions on my site... I 
started the site before the CLARC page was available, but they beat me to 
it, so I only hastily finished mine-- and I apparently forgot the satellite 
and ATV antennas.

Anyway, the dimensions are from the Reflector.. at my sight the spacing of 
the reflector is marked "0" to help alleviate this confusion.

Fred W0FMS

>From: "Keith O'Brien" <n4zq@ij.net>
>To: "Frederick M. Spinner" <fspinner@hotmail.com>
>Subject: Re: [amsat-bb] Cheap Yagi
>Date: Fri, 29 Jun 2001 10:22:46 -0400
>
>Thanks Fred for the info and I am building the Sat version. The only other
>question I have is the element spacing. Is the element spacing measurement
>all referenced from the REF? Or is it from the DE? In other words is it, on
>the 435 11 element model, 2.50 inches from the REF to the DE. Then is it
>5.50 inches from the REF to D1 or is it 5.50 inches from DE to D1?  Then
>11.25 inches from REF or DE to D2, so forth and so on. Any help be
>appreciated. Also I take it you have used one of these antennas and if so,
>what you think of it? TNX & 73 Keith N4ZQ
>
>
>
>----- Original Message -----
>From: "Frederick M. Spinner" <fspinner@hotmail.com>
>To: <n4zq@ij.net>
>Sent: Friday, June 29, 2001 10:00 AM
>Subject: Re: [amsat-bb] Cheap Yagi
>
>
> > If you are building the 435 "AMSAT" antenna there is no error.  On the 
>432
> > terrestrial one of the driven elements is shown to be an inch too long--
> > it's obvious if you look at it as the directors are supposed to always 
>get
> > shorter and that one is longer than the one before it.
> >
> > Fred W0FMS
> >
> >
> >
> >
>

_________________________________________________________________
Get your FREE download of MSN Explorer at http://explorer.msn.com

----
Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org



AMSAT Top AMSAT Home