************************************************************************ How to upgrade your 24oo modem into a 96oo baud. (US Robotics compatible of course Written B Death Bringer (CPT/Info-Net/IRA 06/7/9 Be sure to turn off your modem before you begin First of all, you need to go to your nearby electronics store, don't tr to go to Radio Shack, their parts have their own model numbers and you'l have a hell of a time getting the parts you need. This upgrading of you modem will not work on old hayes modems, but they will work on any clon maker of modems (everex, practical peripherals, anchor, ati, intel, etc. It will only work with modems with the Intel Chipset This technique widens the band width by using a different chip that i similiar to the chip already in your modem Parts Needed 16550 UAR L4313545 I SC11020CN I L8730183 I First of all, check to see if your biggest chips are soldered or socketed if they are soldered, you'll have to de-solder the chips before you begin After you get that done, replace the 8250 UART with the 16550 UART. (1655 UARTs are required for 9600+ speeds). The other 1 or 2 chip(s) need(s to replaced with INTEL L4313545 instead of the chip that is already there If your modem has another socket or more, than you are in luck, you ca purchase a chip from US Robotics, and make your modem faster than 9600 If you don't have the socket, than you can only go 9600. I'll get th chip number to you in the next edition and explain how and where t install it. I am working on a way for the people (like me) that do not hav the extra socket in their modem to speed up the rates. I am working on a wa to piggy back the chip. I'll get back to you. There should be a 22 pi chip on your modem also with a model number of SC11005CN or some where clos to it. Replace it with the SC11020CN. Also, replace the L8630173 with th L8730183 chip. If you have any suggestions or questions, you can locate me through Compuserve USER ID 74702,9752 *****OPTIONAL, LAP-M Error correction**** Adding error correction is rather simple. For this these parts ar necessary Potentiometer. This is a 5k audio taper variable resistor Capacitor. Any non-polarized 1.0 to 1.5 uf cap should do 100 ohm resistor - quarter or half watt Wir Solder, soldering iron, etc Solder one end of the capacitor to PIN 1 of the phone line input jac |------------------- | \ line in : | \ phone in : |-----------||||||||| pin 1 If your modem is external, the diagram looks like this |------------------ | / | ||RS-232 por | \| : | |-|line in : | |-| pin 1 | |-|phone i | |- |------------------ This should be on the back of the modem Pin one should the farthest on the bottom left Solder the other end of the capacitor to the center lug of the potentiomete (there are three lugs on this critter). Solder one end of the resistor to th PIN 4 of the line input jack. Solder the other end of the resisto to either one of the remaining outside lugs of the potentiometer. Doesn' matter which one ------------------------------------------------------------------------ ADDITION TO ORIGNAL FILE - 6/15/91 Bill McCauley & Dark Spyre/Dr. Brains/Ryan Schwartz/Lamer/Lose First, a personal recomendation. _THIS WORKS!!!_ I have been plagued wit 2400 baud for some time. I hate waiting for the transfer to finish so tha i can use the phone. Threw the gismo together in about 10 or 15 minutes took another five to adjust the pot for best results on my wors conection, and guess what? No more slow connections ------------------------------------------------------------------------ Have Fun of course I am working on cheap ways to install V.32/V.42bis on your modified mode **************