SB-864 Speaker Mic for TR-2400 3-20-83 The SMC-25 Speaker Microphone may be adapted for use with the TR-2400 by performing the following: Parts Required: Qty Part No. Description 1 E30-1628-08 SMC-24 Cable Assembly 1 J42-0429-08 SMC-25 Bushing Procedure: 1. Remove the three chrome and one black Phillips head screws from the microphone case. 2. Seperate the case falfs and remove the PTT switch, the microphone and the speaker assembly. 3. Carefully pry the brass clamp from the SMC-24 cable assembly, and remove the hard rubber bushing. 4. Slide the SMC-25 bushing (J42-0429-08) onto the cable and replace the brass clamp. 5. Remove the SMC-25 cable assembly from the speaker, PTT switch and the microphone. Leave the small resistor (Parallel cap on some models) connected to the mic element for now. Also save the small black and the small brown wire from the SM-25 Cable. 6. Solder the white wire from the SMC-24 cable to one side of the resistor on the mic element and the small brown wire to the mic element at the other side of the resistor. The resistor and capacitor may now be removed. 7. Assemble the remaining components: Short black wire to center pin of PTT switch, red wire to switch common, Blue wire to one side of the speaker, and the remaining wires to the other side of the speaker (1 short brown, one long brown, and one short black. 8. Replace the back cover, and lapel clip, to complete the procedure. *Note: This change may be performed at the owners option and may not be performed in warranty. JEB/sh (c) 121589TKC