Anyway, I found 4 other base stations beside my own.
But get this ... when I pulled out of my house, the thing was working like a champ, detecting my own signal until I was a bit down the street. When I came home it didn't start detecting until I'd been sitting in my driveway for 5 or 6 seconds.
Which suggests ... I can poll iwconfig as often as I want, but either the driver or the hardware itself is backing off its detection rate, perhaps in effort to save battery power and the strength reported by iwconfig at any given time is likely bogus.
So now what I need to do is research how to change that ... if it's controlled by the driver, that should be not-so-hard. If it's in hardware, I might be screwed. Or, I'll just have to downgrade to war pedaling: laptop in backback, headphones on (connected to laptop) ... biking around neighborhoods ... heh.
Did some research. Looks like I need to force the card into CAM (constant awake/access mode) which'll take 10x the power, but whatever.
More research: drivers/net/wireless/orinoco.c ... dldwd_ioctl_{set/get}power ... prq->flags & IW_POWER_MODE ... looks like it'll be quite easy.
Wait, damn ... iwconfig lets you set it also! Doh! Helps to read man pages ahead of time. heh.