FM antenna question

elnaldo

Lunatic Member

• Sep 6, 2012

• #1

Hi,

I'm building one of this "T" shaped dipole antenna using 300 ohm flat cable shown in several HOWTO on the web. (like this one: How to build a better antenna)

Can I do #2 instead of #1 ?

 

westend

Audiopile

• Sep 6, 2012

• #2

Yes, but his math isn't the best. There's more to antenna design and tuning than what the linked author covers.
FWIW, I just built two antennas this weekend. A tuned J-pole for FM and a UHF antenna for digital TV.

J-pole tuned to 90 mhz:

Gray-Hoverman UHF array:

 

elnaldo

Lunatic Member

• Sep 7, 2012

• #3

Is his math so wrong? I just want to have a better reception inside my aparment. I have just a piece of wire right now, and the reception is acceptable, I want to improve it, nohing special.

But if #2 is worst than #1,I'd stay with the "T" design.

If it's the same, I prefer #2 to place the antenna in a better place.

 

BinaryMike

Pelagic EE

• Sep 7, 2012

• #4

Try an "Extended Double Zepp." It's just as simple, but the extra length adds 3dB of gain over a dipole. Here's one reference: http://www.g3zps.com/Page4.htm

 

westend

Audiopile

• Sep 7, 2012

• #5

elnaldo said:

Is his math so wrong? I just want to have a better reception inside my aparment. I have just a piece of wire right now, and the reception is acceptable, I want to improve it, nohing special.

But if #2 is worst than #1,I'd stay with the "T" design.

If it's the same, I prefer #2 to place the antenna in a better place.

Click to expand...

Excuse me, Elnaldo, my previous post was a bit judgemental. I've just been lost in a whirlpool of antenna research the past week. :sigh:
Absolutely, build the twin lead antenna and see how it helps your system. Terminating the lead outs in the #2 figure, above, will lessen the gain slightly but how much and if that effects your reception on certain frequencies is dependent on your particular situation. If you are tuned to broadcasters that are close and you have little interference, either of the two examples of twin lead you posted may do an excellent job.

 

elnaldo

Lunatic Member

• Sep 8, 2012

• #6

Thank's ! I wired everything today, used #1 "T" shape. The reception is perfect now.

I'll start to study a bit more, and try that "zepp" later...

My next project: restore this receiver for a friend: http://www.youtube.com/watch?v=nmXtRTRAwAU

I can try the double zepp here