Frequently Asked Questions

MBC-1.5 Display Signal and Cables

When planning an MBC-1 installation, common questions are:

• "How many displays can be connected to a single MBC-1.5?"
• "How far away from the MBC-1.5 can the display be?"

There is no single answer to these questions. The questions are directly related and it depends on the conditions. The issue is signal strength. Each display added effectively reduces the overall distance that a single display can be.

We have tested a single Beta-Brite at 1000 feet which is well beyond the 50 feet maximum of the original RS-232 specification. The test occurred in a relatively noise-free environment using Belden 9451 cable. Your results may vary.

Cable Quality

Cable quality is a greater factor at longer distances and when multiple displays are used. As a general rule, use the highest quality cable that is cost effective for the job. A large gauge wire is not typically needed. Shielded, twisted-pair cable usually works well especially in electrically noise environments.

Signal Extension

RS-232 signals can be boosted for use over very long distances. A short-haul modem can extend RS-232 signals for a mile or more. These can be expensive and are probably overkill for a typical MBC-1 installation.

A cost-effective, practical solution is to use a simple RS-232 extender device. These devices are inline repeaters and their presence is transparent to the MBC-1 and the display(s).

There is no hard rule for how much more distance an extender will allow. It depends on the repeater, the cable and the environment.