Looks like OpenWRT turns up the transmit power to 255 when it starts up on the Linksys WRT54G. Not good...
WiFi IEEE 802.11b/g ESSID:“theinternetco.net” Nickname:“acrux”
Mode:Managed Frequency:2.462 GHz Access Point: 00:0F:66:E3:FC:A8
Bit Rate:24 Mb/s Tx-Power=31 dBm Sensitivity=20/200
Retry min limit:8 RTS thr:2347 B Fragment thr:2346 B
Encryption key:off
Link Quality:255/0 Signal level:-41 dBm Noise level:-7 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0
Good strong signal ... outpaced several orders of magnitude by noise.
After a wl -i eth1 txpwr 40...
WiFi IEEE 802.11b/g ESSID:“theinternetco.net” Nickname:“acrux”
Mode:Managed Frequency:2.462 GHz Access Point: 00:0F:66:E3:FC:A8
Bit Rate:54 Mb/s Tx-Power=31 dBm Sensitivity=20/200
Retry min limit:8 RTS thr:2347 B Fragment thr:2346 B
Encryption key:off
Link Quality:16/0 Signal level:-55 dBm Noise level:-126 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0
Nice and clean!