Epson MFJ-1278B Method 2 Accessory Jack or Interface Box Connection, Accessory Jack Interface

MFJ-1278B MULTI-MODE RADIO INTERFACING

The bandwidth of the receiver audio will have an effect on modem sensitivity to false DCD. Some receivers produce wideband audio that will NOT produce any false DCD activity regardless of the threshold control setting. In this case, set the DCD threshold control to its maximum clockwise rotation. This will not effect modem performance.

Method 2: Accessory Jack or Interface Box Connection

If your radio has an accessory jack with PTT, transmit audio, and receive audio signals, the interconnection can be done through this jack (shown in Fig. 3-6).

Fig. 3-6 Accessory Jack Interface.

If your radio does not have an accessory jack and you don't wish to add a connector to your radio, you may construct a separate external interface box. This box will permit simultaneous connection of your MFJ-1278B and a microphone. Figure 3-7 shows a schematic of an external interface box.

A microphone interface box similar to the one shown in Fig. 3-7 is available from MFJ Enterprises, Inc. or from any dealer of MFJ products. The Model No. of the microphone interface box is MFJ-1272B.

Regardless of whether you use an accessory jack or an external interface box, you should use shielded wire for all signal carrying leads. The connectors and fittings on your radio will be the deciding factor, as to what hardware you will need. The user may also want to refer to manuals of the equipment involved in the interconnections for some information.