wireless problem

[Paul Murtaugh]

I have an Actiontec DSL modem broadcasting a wireless signal
to my laptop (Fedora Core 2) via a ZoomAir Model 4100 pc card, 
with no security.  The connection used to work fine -- so I
don't think it's a configuration issue -- but lately it has 
been near impossible to establish the connection and, once
established, it often fails.  A friend's laptop picked up the 
router's signal without any trouble, so I'm wondering if there's 
something wrong with the ZoomAir card.  Any advice on how to 
debug this problem would be greatly appreciated.  An example of
the kind of trouble I've been having:

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[root at localhost paul]# /usr/local/sbin/iwconfig eth0 essid ACTIONTEC key off mode Ad-Hoc

# at this point the blinking light on the card becomes solid, but ...

[root at localhost paul]# /usr/local/sbin/iwconfig
lo        no wireless extensions.
 
eth0      IEEE 802.11-DS  ESSID:"ACTIONTEC"  Nickname:"Prism  I"
          Mode:Ad-Hoc  Frequency:2.457 GHz  Cell: 02:40:31:EB:B4:55
          Bit Rate:2 Mb/s   Tx-Power=15 dBm   Sensitivity:1/3
          Retry min limit:8   RTS thr:off   Fragment thr:off
          Encryption key:off
          Power Management:off
          Link Quality:0  Signal level:0  Noise level:0
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0
 
[root at localhost paul]# /sbin/ifup eth0
 
Determining IP information for eth0... failed.

[root at localhost paul]# dmesg
divert: allocating divert_blk for eth0
eth0: Station identity 001f:0009:0001:0004
eth0: Looks like an Intersil firmware version 1.4.9
eth0: Ad-hoc demo mode supported
eth0: IEEE standard IBSS ad-hoc mode supported
eth0: WEP supported, 104-bit key
eth0: MAC address 00:40:36:01:B4:55
eth0: Station name "Prism  I"
eth0: ready
eth0: index 0x01: Vcc 5.0, irq 3, io 0x0100-0x013f
ip_tables: (C) 2000-2002 Netfilter core team
pnp: Device 00:07 activated.
parport: PnPBIOS parport detected.
parport0: PC-style at 0x378, irq 7 [PCSPP]
lp0: using parport0 (interrupt-driven).
lp0: console ready
eth0: New link status: Association Failed (0006)
ACPI: PCI interrupt 0000:00:02.7[C] -> GSI 10 (level, low) -> IRQ 10
intel8x0_measure_ac97_clock: measured 49401 usecs
intel8x0: clocking to 48000
eth0: New link status: Disconnected (0002)
eth0: New link status: Connected (0001)
ip_tables: (C) 2000-2002 Netfilter core team

[root at localhost paul]# tail /var/log/messages
Sep 13 09:32:57 localhost kernel: ip_tables: (C) 2000-2002 Netfilter core team
Sep 13 09:33:00 localhost dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 3
Sep 13 09:33:03 localhost dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 8
Sep 13 09:33:11 localhost dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 8
Sep 13 09:33:19 localhost dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 7
Sep 13 09:33:26 localhost dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 11
Sep 13 09:33:37 localhost dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 8
Sep 13 09:33:45 localhost dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 9
Sep 13 09:33:54 localhost dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 7
Sep 13 09:34:01 localhost dhclient: No DHCPOFFERS received.
 
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-Paul