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Modem static when dialing [help, stuck with 33.6 WinModem]

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OK, I moved one of my SCSI drives from an external enclosure into my computer. After restarting the machine, I was having trouble connecting with my modem, so I did the first thing I always do when I have modem problems: I hit speakerphone on my desk phone and listen to the line as I try to dial-up.

 

I get a clear dial-tone, but as soon as the modem opens the port to connect, a whole bunch of static just clogs the line, and the modem can no longer hear the dial-tone, and stops with an error: "no dial-tone".

 

The static comes in the second the port is open, so it's not an incompatibility with the TelCo, or ISP. I thought it might be a power problem, so I unplugged the SCSI drive. No help. Thought there might be some cross-talk between the SCSI cable that was now running right over the modem, so I unplugged that too. No help. Bus-master problem, maybe? - moved to another PCI slot. No help.

 

So, now I'm running on an old USR 33.6 ISA WinModem from my 486, that connects at like 26k on good days. The 56k is a cheap CompUSA modem, but has not had these problems until now [it's about a month old]. The phone line is plugged in to the correct jack on the modem [i've tried it in both].

 

My next test will be running the line through the 33.6 modem, back into the 56k modem and see if that changes anything, which I doubt it will. Any idea what could be causing this? Any one have this happen to them? All help [and attempts] is appreciated.

 

-bZj

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This problem usually caused by ISA data interface failures, commonly from Schottky data buffers suffering an excessive static charge from PCB handling, sometimes by greater noise and ringing being in a less than quality ISA slot, which can be compensated with moving to an ISA slot nearest adjacent to the PCI slot, or cleaning the dirty, oxidized finger contacts. Unless the modem is a single chip intergrated design, you normally can fix this data buffer failure... replacing the chips designated 74xx14, 54xx14, or equivalent 4K series nearing the ISA card edge.

 

OOPS... forgot to include same problematic symtoms from an OC'ed ISA bus.

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