If the intermittent signal was due to it being weak but continuously transmitting, depending on where your receive antenna is mounted on your Bird, you probably could'a nailed that thing with the wing-null method of DFing along with the signal strength.
It's becoming a lost art, however, even in CAP. The Becker makes things way too easy. No one listens to the sweeps to get a feel for strength, multipath, nulls... Sigh.
If intermittent because it was going on and off, that's a bit trickier.
Funnest ELT chases yet were the one in the USPS boxcar at the railyard, and the one in a glider being towed from Boulder, CO to just south of Golden, CO by a kindly old German fellow who was worried he was in trouble when four vehicles descended on his campsite in rapid succession.
The group's basically defunct now, but we still have receivers on 121.5 and 243.0 at a number of local airports.
http://www.fredf.org
There were so few people responding to them, and their backup batteries have all failed, that the alert mode has been turned off. There's maybe four of us who remember how to command them to play whatever they're hearing out over a local UHF repeater anymore.
Interest waned, people got older, and very few ELTs over the last decade as flying activity went down or ELTs got better (and moved to 406 for some) mean that the group is pretty dead now.
Mix that with CAP's retarded requirement that an "Urban Ground Team" consist of a minimum of two people, so they rarely "come out and play" anymore either, and ELTs around here run for hours and hours.
I really don't need someone in the passenger seat of my truck to help me find an ELT. I had enough brains to pull over, take bearings, draw on a map, and then drive.
Re-tar-ded.
Was more fun when ten of us would show up, find the stupid thing in the first half hour, wait another two for someone to notify the owner, and have them open up the hangar, and then go have mexican food somewhere and talk.
The L-Per sits in my garage, gathering dust. It's so old the practice beacon frequency in it is still 121.6