Midian IS-1 User Manual

Manual Revision: 2011-10-11

Covers PCB Revisions:

B

IS-1

Interoperability Switch

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TABLE OF CONTENTS

Specifications 3
General Information 4
Hardware Installation 5
Hardware Alignment 6
Dip-Switch Settings 6
Controls & Indicators 7
Operation 8
IS-1 Option C 9
Theory of Operation 10
Technical Notes 11
Contact Information 11

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SPECIFICATIONS

Voltage/Current:

Internal Battery Voltage 9.6 Volts Alkaline
Battery Capacity ~565 mAh
Battery Life (estimated) 45 hours
External Power from Radio 6 - 18 VDC
External Power from Optional Wall Adaptor 12-18 VDC
Current with Power LED ~11 ma
Current VOX or PTT LED 2 ma

Radio Inputs/Outputs:

Audio Input Level 50 mVpp – 20 Vpp
AGC Dynamic Range 50 db
Audio Output to Mic Circuit Constant 1.3 Vpp or 0.65 Vpp Dip-Switch Settable
Audio Output Impedance 1 k or 47 k Dip-Switch Settable

COR Input Logic Low
PTT Out: Open-Collector – Logic Low

Mechanical:

Dimensions: 1.85" H x 5.1” W x 5.3" L
Operating Temp: -30° to +60° C

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GENERAL INFORMATION

The IS-1 is designed to permit interoperability between two radios of virtually any type. It can be used as a cross
band repeater between a VHF and a UHF radio. It can allow interoperation between a Military HF SSB radio and
an APCO 25 radio or between a MotoTRBO radio and a Kenwood NEXEDGE radio. It can be used between
mobile and portable radios. It may be battery operated for up to about 50 hours when using two portable radios or
may use an optional wall charger. When using mobile radios it can derive its power from the radio.

The IS-1 takes the receive audio from one radio “A” and feeds it into the opposite radio “B’s” microphone circuit.
When using portables the receive audio from radio ”A” is detected by the IS-1’s VOX circuit keying radio “B” which
passes the above mentioned audio to radio “B”.

When using mobile radios, the VOX is not used and instead the IS-1 converts the COR from radio “A” to a push to
talk signal keying radio “B”.

There is a monitor output jack that can be used for recording or monitoring audio with an earphone or speaker
amplifier.

The IS-1 Option C is an optional DTMF, 5-Tone, 2-Tone or Pulse Tone decoder to activate and deactivate the unit
from field radios using the keypad on the radio or an ANI sequence on a dedicated channel. The decoder will
transpond once after activation and twice after deactivation.

The IS-1 Option D is an option Morse Code identification option for in-band use.

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HARDWARE INSTALLATION

Be certain to follow standard anti-static procedures when handling any of Midian’s products.
Use the enclosed matching cables with RJ45 type connectors to plug into the IS-1. The other ends can be

connected to the appropriate type of radio connector using the pin out and color codes show below. See
connector pin out in the chart below.

Midian offers several pre-made cables for plug and play operation for certain radios. Contact sales for further
information.

Radio 1 uses connector J1 with the following connections:

J1-3: Mic audio (White): Connect to the MIC-High in Radio 1.
J1-4: Ground (Black): Connect to ground in Radio 1.
J1-5: COR Input (Red): Connect to a point in the radio’s squelch or CTCSS circuit that changes logic level when

a carrier is detected.
J1-6: External Power (Green): Connect to a 6-18 VDC source in Radio 1. If power cannot be connected to the

radio use the 9.6 Volt battery power or the optional wall adaptor (12-18 VDC).

J1-7: PTT Out (Yellow): This open collector provides a ground during PTT. Connect this to the PTT of Radio 1.
J1-8: Speaker – (Violet): Connect to Speaker - of Radio 1.
J1-9: Speaker + or Single Ended Speaker High (Orange): Connect to Speaker + of Radio 1.

Radio 2 uses connector J4 with the following connections:

J4-3: Mic audio (White): Connect to the MIC-High in Radio 2.
J4-4: Ground (Black): Connect to ground in Radio 2.
J4-5: COR Input (Red): Connect to a point in the radio’s squelch or CTCSS circuit that changes logic level when

a carrier is detected.
J4-6: External Power (Green): Connect to a 6-18 VDC source in Radio 2. If power cannot be connected to the

radio use the 9.6 Volt battery power or the optional wall adaptor (12-18 VDC).

J4-7: PTT Out (Yellow): This open collector provides a ground during PTT. Connect this to the PTT of Radio 2.
J4-8: Speaker – (Violet): Connect to Speaker - of Radio 2.
J4-9: Speaker + or Single Ended Speaker High (Orange): Connect to Speaker + of Radio 2.

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