Description
Unisys MDM 2400 USA MDM24US External Modem RS-232C RJ11C 2400 Baud No PSU
External dial-up modem manufactured by Unisys in the early 1990s. Connects to RS-232C serial ports on computers to establish telephone line connections at 2400 baud data rate.
Specifications & What's Included
- Data Rate: 2400 bps (2400 baud)
- Interface: RS-232C DB25 connector
- Phone Line Ports: TO LINE and TO PHONE (RJ11C/RJ12C/RJ13C)
- Power Requirements: 8.5 VAC (adapter not included)
- Form Factor: External desktop
- FCC Compliance: Part 15 Subpart J, Part 68
- Date Code: 94-01382 AA
Applications
This modem type was standard for dial-up connectivity on Unisys PC systems and any computer with an RS-232C serial port during the 1990s. Used for remote access, bulletin board systems (BBS), and general internet connectivity before broadband adoption. Compatible with legacy DOS and early Windows systems that featured DB25 serial ports.
Condition: Used
This Unisys MDM 2400 USA (MDM24US) external modem has been inspected and powers on. It has not been further tested beyond powering up at our facility. The plastic casing shows significant yellowing consistent with age — typical of equipment from this era stored over time. The front LED indicators and rear connectors (RS-232C DB25, TO LINE, and TO PHONE RJ11 jacks) appear intact and undamaged. No AC adapter is included; the unit requires an 8.5 VAC external supply which is not in stock with this listing. Please view our photo set and contact us if you have any questions. Please note: We have multiple units in stock — yours may not be the one shown in the photos, however, it will be similar in condition and function.
This Unisys MDM 2400 USA (MDM24US) external modem has been inspected and powers on. It has not been further tested beyond powering up at our facility. The plastic casing shows significant yellowing consistent with age — typical of equipment from this era stored over time. The front LED indicators and rear connectors (RS-232C DB25, TO LINE, and TO PHONE RJ11 jacks) appear intact and undamaged. No AC adapter is included; the unit requires an 8.5 VAC external supply which is not in stock with this listing. Please view our photo set and contact us if you have any questions. Please note: We have multiple units in stock — yours may not be the one shown in the photos, however, it will be similar in condition and function.
Warranty Information
We stand behind every item we sell with a 30-day money-back guarantee. If your item arrives not as described, you may return it within 30 days for a full refund. Please inspect your purchase upon arrival and contact us with any questions.
View AllClose
Additional Information
Brand: |
Unisys |
Model: |
MDM24US |
MPN: |
MDM24US |
Secondary Model: |
312UUS |
Type: |
External Dial-Up Modem |
SKU: |
8569 |
Data Rate: |
2400 Baud (2400 bps) |
Interface Type: |
RS-232C (DB25) |
Connector Type: |
RJ11C, RJ12C, RJ13C; RS-232C DB25; 8.5 VAC barrel |
Phone Line Ports: |
TO LINE, TO PHONE (RJ11C/RJ12C/RJ13C) |
Power Requirements: |
8.5 VAC (AC adapter not included) |
FCC ID: |
BFJ9D93108US |
FCC Registration Number: |
BFJ9D9-19686-MD-E |
Ringer Equivalence: |
0.7B |
Required Connector: |
RJ11C, RJ12C, RJ13C |
FCC Class: |
Class B Computing Device (Part 15, Subpart J) |
Form Factor: |
External Desktop |
Standards Compliance: |
FCC Part 15 Subpart J; FCC Part 68 |
Seller Notes: |
Powers on; AC adapter not included. Yellowed casing. No AC adapter in box. |
Country/Region of Manufacture: |
United States |
Compatible With: |
Unisys PC systems; RS-232C serial port computers |
Era / Vintage: |
Early 1990s (date code 94-01382 AA) |
Condition Notes: |
Unisys MDM 2400 USA MDM24US external modem. Powers on; not further tested. Significant yellowing on casing. RS-232C, TO LINE, and TO PHONE jacks present and intact. No AC adapter included. Sold as-is. |
Condition: |
Used – Powers On; AC Adapter Not Included; Yellowed Casing |
