O.K. Back to the basics...

SWR 1:4 (Actually 4:1)
I assume you swept the frequency, and this is the lowest SWR in the band.

That means you are seeing either 50/4 ohms, or 50 * 4 ohms.

I'd be real suspicious of Feed line radiation.
(The outside of the coax is part of your radiator.)
Do you have a choke flange?  (Current balun)?

If not, try wrapping a few turns of the feed line in a coil at the feed
point.
You can also wrap a few turns before the rig!
Then re-measure the SWR.

  *
  |  __O    Thomas C. Sefranek   WA1RHP@ARRL.NET
  |_-\<,_   Amateur Radio Operator: WA1RHP
  (*)/ (*)  Bicycle mobile on 145.41, 448.625 MHz

http://hamradio.cmcorp.com/inventory/Inventory.html
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> -----Original Message-----
> From: pic microcontroller discussion list
> [mailto:PICLIST@MITVMA.MIT.EDU]On Behalf Of Milan Pavlica YU7XW
> Sent: Sunday, December 29, 2002 9:59 AM
> To: PICLIST@MITVMA.MIT.EDU
> Subject: Re: [OT]: (Stupid) Antenna question..
>
>
> I know all theory, i calculated, and when i connected to my FT101Z, i had
> SWR 1:3 and 1:4 !!!!
> Where i got wrong?
> I have dipole l/2 for 80m and works 100% - 3.737 SWR is 1:1.2 :)))))
> Now, on 21MHz i have a problem...
> Where i am getting wrong....
>
> "Rick C." wrote:
>
> > Wasn't this question part of your exam to get your license? The answer
> > should also be in your study guide.
> > Rick
> >
> > Milan Pavlica YU7XW wrote:
> >
> > > ...Hi!
> > > I need to made a quick dipole for 21MHz
> > > I have only:
> > > RG213 from radio-to-antenna
> > > It is important not to use balun or any twin leads etc etc etc
> > > Just simple wire conected to RG213
> > > Any ideas?
> > > What length of wire need to be?
> > > THANKS!
> > >
> >
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>

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