[50mhz] Using a 6m dipole on 2 meters

[Guy Wire]

John,
You reversed the info from MFJ in your question...it is NOT a 6m dipole that
works on 2m...it is a 5/8 over as 5/8 that works as a 1/2w dipole on 6 (you
can do the same thing with a Larsen, etc NMO-150...it works on 2 AND 6, but
a NMO47 or NMO-50 cut for 6m WONT work on 2m)...remember a 5/8wave is
electrically matched to "look like a 3/4wave" on 2 (thus odd N multiple of a
1/4wave with same base impedance, etc)....a 3/4w electrically on 2 is a
1/4wave physically on 6 (note the difference)...a 3/4wl over a 3/4wl on 2
looks like a 1/2 on 6m but that's electrically also.....a regular 1/2 wl
physical dipole on 6 will not have the matching network, etc. to allow it to
resonate correctly on 2m..You can try it....but I bet the SWR will be off a
bit and it will resonate HIGH outside the band (around 150MHz).
Ive used the 1764s on 6 only....had them in a cross dipole mode (for CP use)
and then bent the element into a V shape to make them more omni
directional......ehhh they worked but I like my PARs better...besides the
cheap ceramic insulators MFJ uses started to crack and the elements never
would stay TIGHTened down..

BTW my PARs survived IKE...I DOUBT the MFJs would have!!! :)

Chris
WB5ITT

-----Original Message-----
From: 50mhz-bounces at mailman.qth.net [mailto:50mhz-bounces at mailman.qth.net]
On Behalf Of John AA5JG
Sent: Monday, September 29, 2008 12:09 AM
To: 50mhz at mailman.qth.net; 6meter at yahoogroups.com; ic706 at yahoogroups.com
Subject: [50mhz] Using a 6m dipole on 2 meters

MFJ makes an antenna called the MFJ-1764, and here is what they say about
it:

"MFJ's stacked 5/8 wave radiators give you more than twice the
omnidirectional gain of a single 5/8 wave radiators! 
Wide 10MHz 2:1 SWR bandwidth...excellent ferrite choke balun feedline
decoupling...shut choke for bleeding off unwanted static... strong
lightweight aluminum. 
Works as an excellent 6 Meter full halfwave centerfed antenna."

I had one of these about 10 years ago and just used it as a 6 meter dipole,
which it seemed to be.  Never used it on 2m that I can remember, but here is
my question-if this is just a 6m dipole that works as 2 stacked 5/8 waves on
2m, will any 6 meter dipole also work like this?  I have the materials in
the back yard right now to make a 6m dipole and will probably do it if I can
use it on 2 meters as well-at least until I get a decent 2m beam back up.

Anyone tried their 6m dipole on 2m with success?

73s John AA5JG
 

________________________________________________________________



 
                   
Moderator: Ray Brown, KB0STN
_______________________________________________
50mhz mailing list
Home: http://mailman.qth.net/mailman/listinfo/50mhz
Help: http://mailman.qth.net/faq.htm
Post: mailto:50mhz at mailman.qth.net