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HARDWARE INSTALLATION
Be certain to follow standard anti-static procedures when handling any of Midian’s products.
P1-4 – Black – Ground – Connect to the nearest ground point.
P1-2 – Red - +5.5 – 15 VDC – Connect to switched B+ in the radio.
P1-3 – Brown – COR/COS – Connect to point in the squelch or CTCSS circuit that changes logic level when
carrier is received. If the point in the radio only makes a minute change, it may be necessary to adjust R2 & R3 to
cause Q1 to change states.
P1-1 – Green – TX Tone Out – Connect to the modulator circuit. Use high impedance point in the radio. In Low-
Z mic circuits, it may be necessary to short R31 and increase C10.
P1-8 – Green/White – Mic Mute – If desired, connect to mic element bias point or to some other point in the audio
amp to crowbar mic audio to ground during ID to prevent voice interference.
P1-5 – Blue – Alert Tone/Speaker Audio – Connect to high side of the speaker. This provides Morse ID, Time-
Out Timer and Go Ahead tones. When using 20-40 Ohm speakers, the onboard resistor in series with Q3 should
be sufficient. When attaching this lead to a 4-8 Ohm speaker, add a 100-Ohm resistor in series with the lead to
limit current.
P1-11 – Gray – PTT In – Used in After PTT mode, this input, when taken to ground, will activate the Morse ID.
Open the radio’s PTT line and connect this wire closest to the PTT input side of the radio. In After PTT mode, if
Common PTT is being used do not open the PTT line in the radio and tie PTT In and PTT Out together.
P1-9 – White – PTT Out – Connect to the output side of the break point mentioned in PTT In above. This keeps
the radio keyed while sending Morse. In After PTT mode, if Common PTT is being used do not open the PTT line
in the radio and tie PTT In and PTT Out together.
P1-12 – Orange/White – Program Input/Message Select Input – For Program In, this lead is connected to the
Green lead from the KL-4 programmer. For Message Select Input, this lead is left floating for Station ID 1 and
grounded for Station ID 2.
P1-13 – Violet – Inhibit Input – When taken to active state programmed in the ID-1 the unit will not transmit the ID
until the state of this input returns to the inactive state.
HARDWARE ALIGNMENT
For the TX Audio Output in a wide band system, set the modulation pot R30 to 3.3 KHz (66% of 5 KHz) of
deviation per EIA specifications. For the TX Audio Output in a narrow band system, set the modulation pot R30 to
1.65 KHz (66% of 2.5 KHz) of deviation per EIA specifications.
