signed for use with each. Note that the ALM-1 has no connector on the equipment end; it can be wired as needed. The cable is attached to the 590T by inserting the modular telephone-type plug in the microphone jack until it locks. To remove the cable from the microphone, insert the small screw driver supplied with the 590T in the rear case hole just above the cable jack to unlock the plug and withdraw the plug from the jack.
HANG UP BUTTON BLUE
Pin
WHITE GREEN BLACK* YELLOW* *COLORS REVERSED ON EARL PRODUCTION UNITS Y A G F D E C B
Color Red
Function N.C. Bias (+), DC Audio Out PTT Switch Hang-up button
Pin 5 6
Color Black White
Function PTT Switch Ground Audio Out NonAmplified Ground N.C.
1 2
3 4
Yellow Blue
7 8
Drain -
WIRING DIAGRAM FIGURE 4
MICROPHONE CABLES
The 590T can be used with various MODULINK microphone cables. Each cable has a modular microphone plug on one end and the user's choice of equipment plugs on the other. The MODULINK Cordset Table supplied with the 590T lists the most popular radios with biased audio available, and the cordset (ALM-) de-
WHT RED GRN GRN S1
F CW G D E C3 .001 R5 150K R4 22 + C2 100x16 C1 1x50 + R3 15K C8 120pF R2 68K
C6 .001
C7 120pF J1
NOTES: 1. ALL RESISTORS 5% 1/4W UNLESS OTHERWISE SPECIFIED. ELECTROLYTIC CAPACITORS IN MICROFARADS X VOLTS, ALL OTHER IN MICROFARADSAND 50V OR GREATER UNLESS OTHERWISE SPECIFIED. 3. * COLORS REVERSED IN EARLY PRODUCTION MODELS.