Washington Apple Pi

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Al Bloom had a lightning strike next to his house a couple years back. It entered the phone line, fried the modem, jumped to the computer and fried the mother board, then fried the hard disk. Ten or fifteen bucks for a modem spike protector is cheap insurance. You can kill two birds with one stone if your computer's surge protector has a built-in modem protector. The good ones often do.

There is nothing odd about the Apple /// that requires a particular modem. Modems that work with other computers will probably work with the Apple ///. However, some modems have switches that must be set in a particular way in order to work with an Apple ///. I recommend that you first try to use the modem the way it is. If it works, copy down how the switches are setup. It may or may not matter, but -- if it does matter -- it's awfully nice to have a written record of what works.

The MultiTech modem I have seems to work with the Apple ///
communication programs using standard modem switch settings. The ADC modem I have, on the other hand, will not work with the Apple /// until I alter two of the switches to be the opposite of standard. The two switches are:

(1)Switch #8: Ignore RS-232 DTR line, TR light always on
The above is the "standard" setting, I flip it to the
other position to use the modem with the Apple ///.

(2)Switch #10:Response to Carrier Detect
The above is the default, I flip it to the opposite
position for the Apple ///.

Using ACCESS /// I can tell if the modem is set up right by noticing whether the characters I type are shown on the screen as I type them. If not, I change the switches until the characters appear.

Dave O. uses a Zoom 14,400 modem, which can be set in software to lower speeds. It is more than the /// really needs, especially since none of our com programs have setting higher than 9600. BUT for uploading files quickly, it IS nice to have. Also, the modem is transportable to other computers in the future.

1.2 Cables

In the realm of cabling, what you want is a straight RS232 modem cable. A modem cable is simply a straight pin to pin cable, nothing fancy. The modem only uses a few of the pins, so some cables only connect those pins. If you get a cable that connects only a few the pins, it will probably work fine. However, a cable with all 25 pins wired is sure to work.

There are some minimal concerns related to connecting the cable to your equipment. Make sure the cable's plugs fit your RS232 connectors at the computer end and at the modem end. IBM PC's and XT's and the like come with male/female connectors because the computer serial port plug is male.

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