Need some help designing a receiving antenna
 

Hi group,

I've been researching this for some hours but can't seem to come up
with some basic info. (This will be my first attempt at DIY antenna so
I still have a lot to learn.)

What I'm trying to do is build an antenna for my Icom R5 handheld
receiver. It uses an SMA connector. What I'm not clear on is what the
internal circuitry of a receiving antenna for a handheld looks like.
I'd like to start by making a 900 MHz suitable antenna as there is a
lot of 900 MHz Ham activity in my area.

I'll be using my trusty mini-lathe and a 1/4-36 UNS thread tap to make
the SMA connector. Q: Does anyone know what the diameter of the male
pin is on the SMA connector? I have the antenna that came with my R5
but can't get into the socket to measure it.

Sure, I could buy a Pryme for $25, but why do that when I can spend $50
and build it myself? ;-)