Topics

Portable FM Telescopic Aerial Testing - 28/03/2020


Paul Blundell
 

With my new focus on the FM broadcast band, I decided to find a way to have a portable FM aerial which would improve the signals I am able to receive on my various ultralight radios.

Following the redesign of my radio case (https://ultralightradiodxing.blogspot.com/2020/03/portable-ultralight-radio-dxing-case.html) I added a mounting point to the top of my case for future use to mount an aerial Over the past few days I have been working on a way to use this. I tracked down an old telescopic aerial from my junk box and mounted this to a piece of wood, this then has a metal mount on the bottom which allows it to connect to the bolt on the top of my radio case.

Tonight I got some time to undertake some testing of this setup, the radio used was my Digitech AR1690.


FREQUENCY - STATION
Internal
External
87.6MHz - TOTE SPORT RADIO
POOR
EXCELLENT
95.3MHz - TAMAR FM
POOR
GOOD
96.9MHz - MEANDER VALLEY FM
NILL
GOOD
98.9MHz - 7AD
NILL
GOOD
101.1MHz - CHILLI FM (CBD)
WEAK
EXCELLENT
102.1MHz - ABC (DEVONPORT)
NILL
WEAK
107.7MHz - SEA FM
NILL
WEAK
 
Comparing the internal aerial (built in) to the portable FM telescopic shows a 2 to 3 level signal increase. Four stations that could not be received at all on the Digitech AR1690 with it's built in aerial, came in when using the portable FM telescopic at varying signals levels. 7AD on 98.9MHz was the real standout and was almost to the level of being able to decode the RDS data. In the photos below you can see the improvement in the signal levels between the built in aerial and the portable FM telescopic.
 





-- 
Paul - Moderator
UltralightDX


radiojayallen
 

Paul,

How long is your rod antenna?

Jay


Paul Blundell
 

At maximum it is 112cm. I normally have it at 72cm which is a 1/4 wave for 100MHz.

On Sun, 29 Mar 2020, 1:49 a.m. radiojayallen, <radiojayallen@...> wrote:

Paul,

How long is your rod antenna?

Jay


--
Paul - Moderator
UltralightDX