Hey Ian,
We fixed it by bending a little approx 1/4 x 1/4 inch tab out of the way so we could see where the antenna connection comes into the radio. When I first looked at it it looked like the issue should have been on this little pin that basically continues on the path of the antenna centre pin into the radio. It has a small loop of wire on it that wraps around it and is soldered pretty good from the factory.
My dad noticed a bit of solder at the (if you're looking at the button side of the scanner) extreme top right on the printed circuit board. There's kind of a tab there that connects to the PCB and goes... somewhere... Anyway he soldered that joint and everything's back up to 5 bars when it should be. I tweaked the bar levels shortly after getting the scanner too so they're less likely to display 5/5 unless you really do have a good signal. I'm back to hearing the Geizer's site at full strength, I was on it (with 4/5 bars) last night while still in Sackville.
So where before, when I needed elastics wrapped around the antenna to keep it pulled to the right so I could get full signal:
(I was progressively adding more through the week to allow it to sit in my pocket without getting messed up again)
It's now been 12 hours without having to touch the antenna at all. I'm not sure WHAT we reconnected, but it seems to be fixed. Maybe the signal from the antenna enters the radio in one spot and then travels in to be decoded or whatever through the connection we corrected last night. As I said it seemed like it would have been on the antenna where it enter the radio but you can't deny that it's looking 100% back to normal. I've had my scanner for about a year and a half, so I know how it should act as I move around town, and it's definitely behaving as it should again.
I'll echo Joe's comments about these radios; the antenna issue was stressful - a 500.00+ radio disabled by a 2 cent solder was crappy, and having to send my radio away for 3 weeks for repair had me in cold sweats
- but the amount of enjoyment I've had and feature list of the 500/106s is _awesome_.
Here's what I mean, since I didn't take pics last night.
In the top of the image is that small square of the shield that we bent. There's the usual culprit screw on one side of the shield and 3 huge blobs of solder on the other. Rather than removing the screw and factory solder we bent the tab as people before have mentioned. That weird orange looking thing at the the left (really the bottom) of the shield is what I thought was broken last week when Gre told me there was probably a wire broken.. That thing looks like a coil spring and impossible to fix.
In the lower part of my pic you'll see the wire (red X) that I thought would be the issue, but the tab (green check) is where my dad saw disconnected solder and did his work. It seems to have fixed things as I said, at least for me. I thought I'd draw this awful pic in paint since the only image on the net I've seen was of the back side of the shield so people could see the screw to tighten. Hope someone gets some use of this!