Collcomm NCS-C151 User manual

NCS-C151
INSTRUCTION MANUAL
Rev B
Collcomm Inc.
d.b.a. NCS
Shipping Address
2310 Pendley Road
Cumming, Georgia 30041
Mailing Address
1595 Peachtree Parkway
Suite 204-123
Cumming, Georgia 30041
Toll Free Tel. & Fax : [phone]
Email : [email protected]
Web Site: www.collcomminc.com
collcomm inc

NCS-C151 Manual Rev B Page 2
Revision History
Rev
Description
Date
App’d
0
Initial Release
07/14/14
JFP
A
Corrected for Trunking Radio on RAD1;
Added Tx Audio Levels; corrected DC
wire size & current consumption
1/7/16
JFP
B
Removed 125mVpp AGC Reference
3/27/17
JFP
Model No.: NCS-C151
Serial No. : ___________________________
Accessory Kit
Item # Description QTY
1 10’ DC Power Cable (NCS-410-PSP-10) 1
2 Mounting Feet 4
3 Mounting Bracket Kit 1

NCS-C151 Manual Rev B Page 3
Table of Contents
Section Description Page
1.0 Introduction 4
2.0 Safety Information 4
3.0 Front Panel Controls 5
4.0 Radio Requirements 5
4.1 Receive Audio 5
4.2 Transmit Audio 5
4.3 PTT 5
5.0 Power Supply 6
5.1 Power Requirements 6
5.2 Power Connection 6
5.3 Polarity 6
5.4 Fusing 6
6.0 Opening Unit to Perform Adjustments 7
7.0 Internal Setup and Adjustments 8
8.0 Trunking Delay Operation 10
9.0 Radio Interface Cables 11
9.1 Radio Interface and AUX Jack Pin-outs 12
10.0 Troubleshooting 13
11.0 Contacting NCS 14
12.0 C151 Specifications 15
13.0 Warranty 16

NCS-C151 Manual Rev B Page 4
1.0 Introduction
The C151 provides a method of connecting two radios together for purposes of
in-band or cross-band repeating.
Almost any radio can be used with the C151. Either VOX or COR can be used
as a “busy” signal and COR polarity can be either + or -. Receive audio levels
do not need adjustment due to built-in AGC circuits for both radios. Transmit
audio levels can be adjusted independently for each radio.
A separate record output is provided that records audio transmitted on either
radio. A record control output is included to control an external recorder.
Typical Application
Conventional Radio –RAD 2 Trunking Radio –RAD 1
2.0 Safety Information
The C151 is an electrical device requiring appropriate safety measures during
installation and operation. The following safety precautions should be
observed:
When connecting the unit to a DC power source, a minimum wire size of
24 AWG should be used. When using in a mobile environment,
automotive grade wire should be used.
Do not route cables or wires through areas that may cause the insulation
to be worn resulting in shorting of the wires to ground or to each other.
Do not attempt to operate this equipment while driving a vehicle. For
safety, pull over to the side of the road when making adjustments.
NEVER connect this device to an AC voltage source. Death or injury could
occur and/or the unit can be badly damaged. Connect this device only to a
DC power source with a voltage output of 9-16 volts and a current
capability of at least 100 ma.

NCS-C151 Manual Rev B Page 5
3.0 Front Panel Controls
4.0 Radio Requirements
4.1 Receive Audio
Receive Audio input levels from the radio are not critical. The Busy lights
activate (when using VOX) at approximately 150mV. Receive audio input
levels are automatically adjusted by an AGC circuit. The AGC circuit for
each radio will produce an output of 1.25Vpp.
4.2 Transmit Audio
Transmit audio levels are separately adjustable for each radio and
sufficient gain is available to drive nearly any radio.
4.3 PTT
PTT is via an Open-Drain output. This signal pulls the PTT line of the
radio low and will key any radio with a low-true PTT requirement.
Maximum switching capacity of the PTT output is 100V, 1.5A DC.
Item
Description
1
Power Switch with Green Indicator
2
Delay Circuit Power Indicator
3
Audio Delay Set Pot
4
Radio 1 & 2 Indicators: Red = Transmit and Green = Receive
1 2 3 4

NCS-C151 Manual Rev B Page 6
5.0 Power Supply
5.1 Power Requirements
The NCS-C151 will operate with any 9-16 VDC power supply capable of
providing at least 100mA continuous.
5.2 Power Connection
Power is supplied to the cable on the rear of the unit. The connector is an
AMP/Tyco Right Angle Two Conductor (P/N 1-770966-0)
5.3 Polarity
Power cable polarity is: Red = +, Black = - (or chassis).
5.4 Fusing
The C151 uses an internal self-resetting fuse. If the fuse opens, there is
likely to be an internal malfunction and the unit should be repaired by a
qualified technician.

NCS-C151 Manual Rev B Page 7
6.0 Opening Unit to Perform Adjustments
Follow the procedure shown below to open the unit up to perform settings and
adjustments:
Rear View of Unit –locate 4 screws
1. Remove 4 screws, rear panel & bezel
2. Slide the whole assembly (both circuit card assemblies) out of the
enclosure. Be careful to secure both boards.
3. Ready for Adjustment

NCS-C151 Manual Rev B Page 8
7.0 Internal Setup and Adjustments
The lower of the two printed circuit board assemblies inside the C151 has
provisions for setting up COR/VOX, COR Polarity and VOX Hang time. To
setup these functions, remove the rear cover of the C151, slide the PCB
Assembly (2 Boards) out of the enclosure and refer to the diagram below
(the lower of the 2 boards) for the locations of settings and adjustments.
The top board does not require any adjustments.
Radio 1 Receive Setup and Transmit
Audio Level Adjustments
Radio 2 Receive Setup and
Transmit Audio Level Adjustments
Record Output Level
Adjustment
Factory Installed Shunts & cables on
Internal Board Connector EXCEPT
POSITION 1.
RADIO1 Setup switches set for Low-
going COR (COR- = ON) and normal
Hang-time (LOW-HANG = OFF).
RADIO2 Setup switches set for Low-
going COR (COR- = ON) and normal
Hang-time (LOW-HANG = OFF).

NCS-C151 Manual Rev B Page 9
7.1 Connect one radio to the RAD1 jack and the other radio to the RAD2 jack
on the rear panel of the C151 using radio-specific Radio Cables. Connect
the power cable to 12VDC.
7.2 Set the COR, VOX and Hang-time settings as required for each radio.
7.3 Turn On the Power switch. The Green “ON” indicator should illuminate.
7.4 Transmit a signal to the radio connected to the RAD1 jack. The green
BUSY indicator for RAD1 should light up and the red TX indicator for RAD2
should light up. This will cause the radio connected to the RAD2 jack to
transmit. Adjust the RAD2 TX level control using a service monitor or another
radio. Stop transmitting.
7.5 Transmit a signal to the radio connected to the RAD2 jack. The green
BUSY indicator for RAD2 should light up and the red TX indicator for RAD1
should light up. This will cause the radio connected to the RAD1 jack to
transmit. Adjust the RAD1 TX level control using a service monitor or another
radio. Stop transmitting.
7.6 This completes Setup.
7.7 Reinstall the two (2) circuit board assemblies inside the enclosure as
follows:
1. Slide the bottom circuit board into the SECOND from the BOTTOM
SLOT on the rear of the enclosure. Slide the top circuit board into the
FOURTH from the TOP SLOT on the rear of the enclosure. Make
sure both sides of each circuit board slide into the corresponding slot
on each side of the enclosure.
TOP Board (4th slot from top)
BOTTOM Board (2nd slot from bottom)

NCS-C151 Manual Rev B Page 10
2. Slide the assembly all the way into the enclosure making sure the
power switch fits through the hole on the front panel
3. When the assembly is all the way into the enclosure, re-install bezel,
rear panel and tighten 4 screws.
8.0 Trunking Delay Operation
8.1 Overview
The NCS-C151 is equipped with a Trunking Delay Module connected to Radio
1 (RAD 1). The purpose of the circuit is to delay the transmitted audio and PTT
release while the Trunking Radio acquires a channel from the Trunking Radio
System controller. This prevents voice transmissions from being lost or
“chopped” during the channel assignment (trunking handshake).
8.2 Setup and Operation
The delay module has an adjustment on the front of the NCS-C151 for setting
the total Trunking Channel Acquisition delay. Turn this control using a small
screwdriver to equal or exceed the maximum delay expected from the trunking
system. Available values (also shown on the unit’s front panel) are: 0ms (no
delay), 50ms, 100ms, 200ms, 400ms, 800ms, 1600ms and 3200ms.
During operation, when the trunking radio is keyed from the C151, the radio will
key for at least the set delay period plus the length of the receive audio time
from RAD 2 (the audio from RAD 2 will be transmitted complete after the time
of the delay set).