Saturday, 19 May 2018

Cheap car radio antenna

For a while my car radio reception has been pretty poor. I suspect it's a poor ground somewhere on the aerial, the aerial itself is a loop in one of the rear windows, so all sorts of problems are potentially there. Also with it being a large car, the wiring run will be long too which won't help.

So rather than fix the problem (!) I decided to look for alternatives, as I know you can buy cheap antennas that fix to windscreens, hidden away, etc, and have an amplifier in it too.
So I trawled various websites and there is very little on reviews on what is good and bad! So I decided to take a look and take a chance on a cheaper powered unit.

This was what I thought I'd try, as it was cheap but still had powered circuitry in it and from a UK seller.

It arrived quickly which was good, so I fitted it into the car. It arrived looking like this:

Two wires marked red and black were for 12v power to it, then it had the standard round connector for antenna into the radio.
I wired it up, and placed it on top of the dashboard, powered on.

Signal was TERRIBLE, really bad. To be honest a bit of wire was probably about the same quality. I'm not sure why it was so pathetic, but it really wasn't working at all.
I checked connections, power, etc, to be sure but no it just was a pile of junk.

So after removing it and swapping back I thought I'd take a look inside the boxes. To my surprise there was actually electronics in there (I was half expecting an empty box!)


I'm going to take a look a the components and circuit as I'm not sure exactly what it's doing. From what I can see there are a few resistors and a couple of either gates or diodes on there, so i'm going to try and figure the circuit out and see what it was trying to do!

The other end looked pretty unremarkable:



I should have known better really!