NCS NCS-C250C User manual

NCS-C250C
INSTRUCTION MANUAL
Rev J
New Communications Solutions, LLC
536 Valley Mist Trace
Suite 101
Norcross, Georgia 30092
Toll Free Tel. & Fax : [phone]
Email : [email protected]
Web Site: www.ncsradio.com

Revision History
Rev Description Date Approved
A 9/8/04 CIF
B 01/21/05 CIF
C Add TOC. General Cleanup 06/06/05 CIF
D CO-C250MANUAL-001 08/08/05 CIF
Combine Option Manual 10/15/05 CIF
F Add S/N, VOX/COR ID, MIC INFO 10/14/06 CIF
G Change Default Shunts 06/22/07 CIF
H Change to B model, impedance jumper
clarification.
10/23/08 CIF
I Change to C model. 08/01/09 CIF
J Corrected Missing Tables 09/14/10 CIF
FACTORY INSTALLED OPTION
IDENTIFICATION TABLE
The Serial Number Label located on the bottom of the unit indicates which Options are
installed according to the following chart:
Option COR HookSwitch Multicast Sidetone
M00
M04 X
M05 X
M06 X X
M08 X
M09 X X
M10 X X
M11 X X X
M12 X
M13 X X
M14 X X
M15 X X
M16 X X X
M17 X X X
M18 X X X
M19 X X X X
NOTE: The COR and Hookswi ch Op ions require ha an Op ion Board be ins alled in he C250C a
he fac ory.
NOTE: If a microphone was ordered with this unit, it has been factory setup
for the supplied microphone listed below.
Microphone: _________________________________
(To change microphone se up, see page 9.)
(circle Busy De ec ion mode for each RAD por ))
COR: RAD1 RAD2 RAD3 RAD4
Model: ___________________________________ VOX: RAD1 RAD2 RAD3 RAD4
Serial Number: ____________________________
NCS-C250C Instruction Manual Rev J Copyright © 2004-2010 New Communications Solutions, LLC
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Table of Contents
1.0 Introduction....................................................................................................4
2.0 Safety Information..........................................................................................5
3.0 Accessory Kit.................................................................................................6
4.0 Front Panel Controls.......................................................................................6
5.0 Radio, Speaker and Microphone Requirements.............................................7
6.0 Power Supply..................................................................................................8
7.0 Microphone Setup..........................................................................................9
8.0 Rear Panel Connections................................................................................12
9.0 Radio Interface Cables.................................................................................14
10.0 Adjustments................................................................................................15
11.0 Operating the C250C .................................................................................18
12.0 C250C Option Board..................................................................................20
13.0 Block Diagram............................................................................................24
14.0 Troubleshooting..........................................................................................25
15.0 Contacting NCS..........................................................................................26
16.0 C250C Specifications ..............................................................................27
NCS-C250C Instruction Manual Rev J Copyright © 2004-2010 New Communications Solutions, LLC
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1.0 Introduction
The C250C provides a me hod of swi ching one microphone or headse and wo speakers o mul iple
radios.
Nearly any dynamic or elec re microphone can be used wi h he C250C . Pin assignmen s,
impedance, level, and elec re mic elemen vol age (phan om vol age) are jumper selec able. A
DTMF microphone can be used for con rolling all fron panel swi ch func ions.
Separa e speaker ou pu s are provided for Selec ed and Unselec ed audio wi h individual volume
con rols and mu e func ions.
A high power PA speaker ou pu and a voice-opera ed cross-band repea er/range ex ender suppor
ou -of-vehicle opera ion.
All swi ches are illumina ed for low ligh or nigh opera ion and LED indica or brigh ness is
au oma ically adjus ed based on ambien ligh o provide easy day or nigh viewing of uni s a us.
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Typical Application

2.0 Safety Information
The C250C is an elec rical device requiring appropria e safe y measures during ins alla ion and
opera ion. The following safe y precau ions should be observed:
•When connec ing he uni o a DC power source, a minimum wire size of 18 AWG should be
used. When using in a mobile environmen , au omo ive grade wire should be used.
•Do no rou e cables or wires hrough areas ha may cause he insula ion o be worn resul ing
in shor ing of he wires o ground or o each o her.
•Always replace fuses wi h he ra ings specified by he manufac urer.
•Do no place your ears in close proximi y o he local speakers or PA speaker a high volume
se ings. Your hearing could be impaired as a resul .
•Do no a emp o opera e his equipmen while driving a vehicle. For safe y, pull over o he
side of he road when making adjus men s.
•NEVER connec his device o an AC vol age source. Dea h or injury could occur and/or he
uni can be badly damaged. Connec his device only o a DC power source wi h a vol age
ou pu of 12-15 vol s and a curren capabili y of a leas 2A.
NCS-C250C Instruction Manual Rev J Copyright © 2004-2010 New Communications Solutions, LLC
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3.0 Accessory Kit
An Accessory Ki is packed wi h he C250C . The following i ems are included in he Ki :
Item Quantity Description
Power Cable, DC 1 10 foo cable for connec ing C250C o DC power source.
Ki , Speaker Connec or 1 Consis s of 1 Plug Housing and 10 each con ac s for 18-22
AWG and 22-26 AWG speaker wire.
Fuse, 5x20mm 2 Spare 3A fuses.
Shun s, Black 30 Used o program he microphone pins.
Moun ing Fee 4 Used for able- op ins alla ion.
Clamp, Power Connec or 1 Used o clamp he C250C power pig ail connec or o he
DC Power Cable.
.0 Front Panel Controls
I em Descrip ion
1 Power Swi ch wi h Red LED Indica or- La ching
2 Radio Selec Swi ches wi h Red Selec ed and Green Busy Indica ors, Momen ary
3 PA/Repea er selec ion swi ch wi h Red RPT and Green PA Indica ors, Momen ary
4 Mu e Func ion Swi ches wi h Yellow Indica ors, Momen ary
5 Volume Con rols for Selec ed Audio and PA (SEL/PA) and Unselec ed Audio (UNSEL)
6 Fron Panel Microphone Jack , RJ45 Modular
NCS-C250C Instruction Manual Rev J Copyright © 2004-2010 New Communications Solutions, LLC
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1 2 3 4 5
6

5.0 Radio, Speaker and Microphone Requirements
5.1 Radio
5.1.1 Receive Audio
Receive Audio inpu levels from he radio should be from 200mVp-p o
500mVp-p. The Busy ligh s ac iva e a approxima ely 150mV. Receive
audio inpu levels are normally adjus ed using he Volume Con rols on he
radios.
CAUTION: When using radios with bridged audio speaker outputs,
connect only one of the speaker output lines to the C250C . Leave the
other speaker output line disconnected and preferably insulated with
shrink tubing. The receive audio return path is via the ground
connection between the radio and the C250C .
5.1.2 Transmi Audio
Transmi audio levels are separa ely adjus able for each radio and sufficien
gain is available o drive nearly any radio.
5.1.3 PTT
PTT is via an Open-Drain ou pu . This signal pulls he PTT line of he radio
low and will key any radio wi h a low- rue PTT requiremen . Maximum
swi ching capaci y of he PTT ou pu is 100V, 1.5A DC.
Some radios use a single line o combine PTT and o her con rol func ions.
These radios may no be compa ible wi h he PTT circui ry of he C250C .
Con ac NCS for informa ion on use of hese radios.
5.2 Speaker
The C250C was designed o drive speakers of 4-8 Ohms nominal impedance. Maximum
power ou pu is achieved wi h 4 Ohm speakers. Speaker power ra ings should be
chosen according o he speaker impedance as shown in his char :
Speaker Impedance
(Ohms)
Minimum Power Rating
(Watts-rms)
Selec ed 4 Ω4
8 Ω2
Unselec ed 4 Ω4
8 Ω2
PA 4 Ω16
8 Ω8
CAUTION: NEVER ground either side of the PA speaker output
terminals. Doing so may damage the audio amplifier in the C250C .
5.3 Microphone
The adjus able amplifier in he C250C allows mos any dynamic or elec re microphone
o be used. Typical inpu level from he microphone should be in he range 50mV-
250mV.
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When using a microphone wi h DTMF capabili y, he DTMF bu ons can be used ins ead
of or in addi ion o he fron panel con rols. For DTMF con rol, he DTMF ones mus be
genera ed in he microphone. The audio level of he ones should no exceed normal
voice level. NOTE: The DTMF Option must be enabled-see Section 10.3. The
diagram below shows he DTMF bu ons ha correspond o he fron panel con rols on
he C250C . No e ha RAD5-RAD8 are only used wi h configura ions using a C250C
wi h a C251 Expansion Uni as an 8 radio swi cher.
1
#0
987
65
32
*
RAD1
UNSEL
MUTE
AUTO
MUTE
SEL
MUTE
PA/RPT
RAD
RAD3RAD2
RAD5 RAD6
RAD7 RAD8
6.0 Power Supply
6.1 Power Requirements
The NCS-C250C will opera e wi h any 9-16 VDC power supply capable of providing a
leas 2A con inuous.
6.2 Power Connection
Power is supplied o he pig ail on he rear of he uni . The connec or is an Anderson
Powerpole PP-15. As par of he accessory ki , a 10 foo power cable is supplied wi h a
ma ing connec or a ached. Connec he power cable o a 9-16 VDC source capable of
supplying a leas 2A. Addi ional connec ors are available from Powerwerx (web si e:
h p://www.powerwerx.com, elephone: 714-570-3303)
6.3 Polarity
Power cable polari y is: Red = +, Black = - (or chassis).
6. Fusing
Bo h power supply lines are fused wi h fas -ac ing 3A 5x20 mm fuses (Wickmann USA
series 191 or equivalen ).
6.5 Using an AC Power Supply
The C250C can be opera ed from any well-regula ed 9-16 VDC power supply capable of
delivering a minimum of 2 Amperes. Vol ages higher han 16V may resul in damage o
he circui ry.
6.6 Power Cable Clamp
The Power Cable Clamp is used o keep he Power Cable from separa ing from he
Power Pig ail in Mobile use.
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7.0 Microphone Setup
The main circui board inside he C250C has provisions for se ing up he microphone
func ions. To se up hese func ions, remove he cover of he C250C and refer o he
diagram below for he loca ions of se ings and adjus men s.
Main Circuit Board
7.1 Front and Rear Panel Microphone Connections
The microphone connec ors on he fron and rear panels accep s andard 8-pin RJ-45
modular plugs. Ei her connec or can be used. The fron and rear connec ors are connec ed
in parallel and bo h use he same pin programming. The func ion of each pin is
programmable using he jumper blocks on he main circui board.
7.1.1 Microphone Pinou s
The RJ45 modular plug pin numbering used on his uni is shown below:
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Radio Transmit
Audio Level
Adjustments
Microphone Setup
Jumpers
Microphone Level
Adjustment
Microphone Level
Indicator L Ds
Front of Board

7.1.2 Programming he Microphone Connec ors
Programming he microphone connec ors is accomplished by se ing he microphone
connec or pin func ions, selec ing he impedance level and connec ing a vol age
supply pin if using an elec re microphone elemen
The diagram below shows he Microphone Se up Area of he main circui board.
Refer o i for he following s eps.
.
Microphone Setup Area
To program he func ions of he pins on he microphone connec ors, use he shun s
supplied in he accessory ki o jumper he appropria e microphone pin numbers o
he corresponding signals on he MIC CONN PIN jumper blocks.
For example, o program he microphone shown in he following char , ins all he PIN
SELECT shun s as shown. NOTE: These shun s are shown in he fac ory defaul
posi ions.
NCS-C250C Instruction Manual Rev J Copyright © 2004-2010 New Communications Solutions, LLC
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Default Microphone Pin-out
MIC
Pin
Shunt
Row Signal Name
Pin 1 ------ N/C
Pin 2 ------ N/C
Pin 3 ------ N/C
Pin 4 J2 MIC Audio
Pin 5 J4 GND
Pin 6 J3 PTT
Pin 7 ------ N/C
Pin 8 ------ N/C
Mic Impedance and
Attenuation Jumper
lectret Voltage Jumper

Microphone Impedance
Selec he microphone impedance using shun s on he Impedance jumper block (J10)
as shown in hese examples:
NOTE: The 200 Ohm position is marked incorrectly on the PC Board. Use the
position shown above. Also, these jumpers can be used as a supplemental
mic level adjustment if the range of the mic pot is insufficient.
Electret Supply Voltage
If he microphone is an Elec re ype ha needs a vol age supply, ins all a shun on
J9:
Auxiliary Supply Voltage
If he microphone requires a separa e vol age supply o opera e a preamp, DTMF
keyboard or similar circui ry, ins all a shun on he AUXV block (J5) a he
corresponding microphone pin number. Also, selec he desired supply vol age, 5V
or 12V using a shun on he AUXV jumper block (J15).
Speaker Connections
For microphones wi h buil -in speakers or for headse s, ins all shun s a he
corresponding pin numbers for Selec ed and/or Unselec ed Audio on he SEL AUD
block (J7) and/or UNSEL AUD block (J6).
NCS-C250C Instruction Manual Rev J Copyright © 2004-2010 New Communications Solutions, LLC
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Hi-Z 600 Ohms
(D FAULT)
200 Ohms
(D FAULT)

8.0 Rear Panel Connections
NAME PINOUT NOTES
MIC
RJ45 Connec ors on Fron and
Rear Panel
Pin func ions se by in ernal
programming shun s.
RAD1-RAD
RJ45 Connec ors on Rear
Panel
Pin Signal Note
1 Transmi
Audio
To Radio Mic Inpu
2 Transmi
Audio
Common
To Radio Mic Inpu
Common or Gnd
3 PTT To Radio PTT Inpu
4 GND Signal Ground
5 Receive
Audio
From Radio Audio
(Speaker) Ou pu
6 GND Signal Ground
7 Hookswi ch Ou o Radio
8 COR In from Radio
Refer o Sec ion 9.0 for
cable informa ion.
Hookswi ch and COR
require Fac ory Ins alled
Op ion Board.
NCS-C250C Instruction Manual Rev J Copyright © 2004-2010 New Communications Solutions, LLC
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NAME PINOUT NOTES
EXPANSION
13 Pin DIN Connec or on Rear
Panel
Pin Signal No e
1 MIC_MIX Microphone Mixer
2 GND Signal Ground
3 PTT Low = True (In/Ou )
4 SLAVE_MIXER Inpu Low=True
5 UNSEL_MIX Unselec ed Radios Mixer
6 SEL_MIX Selec ed Radio Mixer
7 EXT_MUTE Ou pu ; Ex ernal Mu e
Logic Level
8 PAD Spare/Fac ory Use
9 GND Signal Ground
10 RX_RS232 Serial Da a In
11 TX_RS232 Serial Da a Ou
12 SLAVE Inpu ; Low = True
13 GND Signal Ground
Used for special func ions.
Mus be enabled by
firmware or special cables.
CAUTION: Pin func ions
vary; Consul fac ory before
connec ing any hing o his
connec or.
EXT MUTE
RCA Phono Jack on Rear
Panel
Cen er Pin - Signal
Shell - Ground
This is an open drain ou pu ha goes low when PTT is keyed, and, op ionally, when
any Busy Ligh comes on (See Sec ion 11.2.5.3)
Maximum Swi ching Capaci y: 100V, 1.5A
This ou pu can be used o
mu e ex ernal equipmen
such as au omobile radios
or can be used o urn on
ex ernal equipmen such as
"On- he-Air" ligh s.
SPEAKERS
Ma ing Connec or:
•AMP/Tyco 172168-1
Plug Housing
•AMP 770988-1 Socke
Con ac s (18-22
AWG)
•AMP 770986-1 Socke
Con ac s (22-28
AWG)
Pin Signal Descrip ion
1 GND Signal Ground
2 SP_BR_2 Bridged Speaker
Ou pu (PA)
3 SP_U Unselec ed Speaker
4 GND Signal Ground
5 SP_BR_1 Bridged Speaker
Ou pu (PA)
6 SP_S Selec ed Speaker
Selected Audio Speaker:
Pins 6 and GND.
Unselected Audio
Speaker: Pins 3 and GND.
PA Speaker: Pins 2 and 5.
All speakers may be
connected at the same time.
NCS-C250C Instruction Manual Rev J Copyright © 2004-2010 New Communications Solutions, LLC
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9.0 Radio Interface Cables
A Radio In erface Cable is required for each radio in erfaced o he C250C . This cable con ains mic
audio, receive audio and PTT signals. I can be fabrica ed from he documen a ion supplied in he
ins ruc ion manual or ob ained from NCS. The cable consis s of an RJ-45, 8 pin modular connec or
on one end for ma ing o he C250C and a radio in erface connec or on he o her end. Un- ermina ed
cables are also available ha require he cus omer o a ach he radio in erface connec or.
There are wo general cable configura ions. The firs is for radios ha have he receive audio
available on he microphone connec or or accessory connec or and he second is for radios wi h a
separa e mic connec or and speaker jack. The wo configura ions are shown below.
RADIO
RADIO
NCS-C250
NCS-C250
RJ-45
RJ-45
Radio In erface Connec or
Radio In erface Connec or
Speaker Cable
Radio In erface Cable
Radio In erface Cable
Mos commercial radios have an accessory connec or ha usually has mic audio, receive audio and
PTT connec ions available and usually is he preferred in erface o he NCS-C250C .
RADIO NCS-C250
RJ-45
Radio In erface Connec or
Radio In erface Cable
Fron
Fron
Accessory Connec or
Specifying Radio Interface Cables
NCS can supply Radio Cables for mos any radios. S andard cable leng h is six fee , however,
cus om leng hs are available. Since here are numerous connec or ypes for in erfacing o various
commercial and ama eur radio ransceivers, he radio model and connec or ype should be specified
a he ime of purchase. A documen describing Cable Specifica ion and Ordering is available on our
websi e a
h p://www.ncsradio.com/documen s/NCS-C250Cables.pdf
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10.0 Adjustments
10.1 Transmit Audio
No e: Transmi Adjus men s can be made from inside or on he bo om of he C250C .
The diagrams below show he adjus men loca ions.
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Radio Transmit
Level Adjustments
Radio 1
Radio 2
Radio 3
Radio 4
Mic Level
Adjustment
Mic Level
Indicator L D
Adjustments Inside the C25 C
FRONT
Transmit Adjustments on Bottom of C25 C
FRONT

Transmi Audio Adjus men Procedure
i. Adjus each radio for proper opera ion using i 's s andard microphone.
ii. Connec NCS Radio Cables be ween he C250C and each radio.
iii. Prese he Mic Level con rol o minimum (clockwise from inside,
coun erclockwise from he bo om, of he C250C ).
iv. Prese all Radio level con rols o midrange (clockwise from inside,
coun erclockwise from he bo om, of he C250C ).
v. Adjus he Mic inpu level as follows:
Connec he microphone o he connec or on he fron or rear panel.
Turn he C250C on and, while speaking in o he microphone, adjus he
Mic Level con rol un il he Mic Level LED ligh s on voice peaks. If he mic
level will no adjus low enough, add an Impedance Jumper in he 600 or
200 Ohm loca ion.
vi. Selec each radio in urn, press he Mic PTT, and adjus he respec ive ou pu
level con rol for proper ransmi er opera ion.
10.2 Receive Audio
If C250C is se up for VOX, adjus he volume con rol on each radio so ha he Busy ligh
on he C250C associa ed wi h ha radio ligh s wi h he lowes level normal received
audio.
10.3 User Programmable Functions
The NCS-C250C has four user programmable func ions. To urn func ions on or off,
perform he following:
1. Deselec all radios.
2. Press and hold he Mic PTT Bu on and he UNSEL MUTE bu on un il bo h he
PA (green) and RPT (red) indica ors above he PA/RPT bu on are illumina ed.
The uni is now in User Programming Mode.
3. The SEL (red) indica ors above RAD1-RAD4 bu ons show he curren s a us of
he func ions. Red Indica or ON = Func ion On.
4. Momen arily press he desired Func ion bu on o oggle he func ion on or off.
5. Momen arily press he UNSEL MUTE bu on o exi he User Programming Mode.
To rese he uni o he fac ory se ings, press and hold he SEL MUTE bu on while in
User Programming Mode. When he PA (green) and RPT (red) indica ors urn off, he
uni has been rese .
DTMF Microphone – Func ion 1
If he DTMF bu ons on a DTMF microphone are o be used o con rol he uni , urn
Func ion 1 ON. If DTMF ones received over a speaker cause false ac iva ion of uni
func ions, urn off he DTMF func ion. The fac ory defaul for his func ion is OFF.
Side one – Func ion 2
This function is a Factory Installed Option. If he Side one Op ion is ins alled in
he uni a he fac ory, his bu on urns Side one On and Off. The Side one func ion
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allows mic ( ransmi ed) audio o be heard in he SELECTED Audio channel (speaker
or headse ). The fac ory defaul for his func ion is OFF.
Mul iCas On/Off – Func ion 3
This function is a Factory Installed Option. The Mul icas Op ion allows he
opera or o selec wo or more radios a he same ime so as o be able o ransmi as
well as receive on mul iple radios. Receive audio from all radios selec ed using he
Mul icas mode will be heard from he Selec ed speaker channel. Keying he mic and
ransmi ing will cause all selec ed radios o be keyed and audio from he mic will be
ransmi ed over all selec ed radios. The fac ory defaul for his func ion is On if he
Mul icas Op ion was ins alled a he fac ory.
Supplemen al Thump Fil er – Func ion 4
In RPT Mode, a variable delay is normally in effec when he ransmi ing radio goes
from ransmi o receive. This delay is necessary for many radios ha crea e a Busy
indica ion when re urning o receive when using VOX repea er con rol. The Busy
indica ion appears o be a valid received signal and i causes he receiving radio o
en er ransmi . If bo h radios produce a Busy indica ion when going from ransmi o
receive, bo h radios would al erna e be ween ransmi and receive wi h no valid audio
signal presen . The buil in Thump Fil er allevia es his problem. The fac ory defaul
se ing for his func ion is Off.
When en ering ransmi , a very few radios produce ano her hump. The
Supplemen al Thump Fil er func ion may be helpful in elimina ing problems due o
his hump.
Function Function Name Button
1 DTMF Mic On/Off RAD1
2 Side one On/Off RAD2
3 Mul iCas On/Off RAD3
4 Supplemen al Thump Fil er On/Off RAD4
This comple es se up and adjus men of he C250C .
NCS-C250C Instruction Manual Rev J Copyright © 2004-2010 New Communications Solutions, LLC
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11.0 Operating the C250C
11.1 Mode and Selected Radio Memory
The curren Mode and he Radio Selec ions for all modes are au oma ically saved in
memory so he C250C will s ay in he same Mode and Radio Selec ion when powered
off and back on. Power failures will no affec he saved s a e of he C250C .
11.2 Normal Mode
11.2.1 Mode Descrip ion
In his mode, only one radio a a ime can be selec ed unless he Mul iCas
Op ion is ins alled (see 10.3). Received Audio from he Selec ed radio is
connec ed o he Selec ed Audio Speaker Ou pu and microphone audio is
connec ed o he Selec ed radio. Received Audio from all Unselec ed Radios
is mixed oge her and sen o he Unselec ed Speaker Ou pu . Keying he
mic will ransmi on he Selec ed radio. The Selec ed radio will be heard on
he Selec ed speaker and all o her radios will be heard on he Unselec ed
speaker.
11.2.2 Selec ing Normal Mode
In Normal mode, nei her he PA nor RPT indica ors are li . If ei her ligh is
on, momen arily press he PA/RPT bu on or he digi "9" on a DTMF
microphone (if enabled) o selec Normal Mode.
11.2.3 Selec ing a Radio
To selec or deselec a radio, momen arily press he desired radio bu on
(RAD1-RAD4) bu on or he corresponding digi (1-4) on a DTMF microphone
(if enabled). The associa ed SEL (red) indica or will ligh when he radio is
Selec ed. The BUSY (green) indica or will ligh when audio is received.
11.2.4 SELECT/UNSELECT Audio Con rol
Received audio from he Selec ed radio will be heard on he Selec ed
Speaker and received audio from all Unselec ed radios will be heard on he
Unselec ed Speaker.
The SEL/PA Volume Con rol con rols volume of he Selec ed radio. No e
ha he SEL/PA Volume Con rol doesn’ comple ely shu off all audio when
urned all he way down. This is normal. To comple ely shu off all audio
from he Selec ed radio, press he SEL MUTE bu on.
The UNSEL Volume Con rol con rols he volume of he Unselec ed radios.
No e ha he UNSEL Volume Con rol doesn’ comple ely shu off all audio
when urned all he way down. This is normal. To comple ely shu off all
audio from he Unselec ed radios, press he UNSEL MUTE bu on.
11.2.5 Mu e Func ions
11.2.5.1 SEL MUTE
To mu e he Selec ed radio, momen arily press he SEL MUTE bu on or he
"*" bu on on a DTMF microphone (if enabled). The associa ed yellow
indica or will ligh and he Selec ed audio will be silenced.
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11.2.5.2 UNSEL MUTE
To mu e he Unselec ed radios, momen arily press he UNSEL MUTE bu on
or he "#" bu on on a DTMF microphone (if enabled). The associa ed yellow
indica or will ligh and he Unselec ed audio will be silenced.
11.2.5.3 AUTOMUTE and he EXT MUTE Connec or
This func ion au oma ically mu es he UNSEL audio and ex ernal equipmen
connec ed o he EXT MUTE jack when PTT is keyed. Also, o mu e ex ernal
equipmen connec ed o he EXT MUTE jack on he rear panel when a
received signal ligh s a green Busy indica or, press and hold he AUTO
MUTE bu on or he digi "0" on a DTMF microphone (if enabled) un il he
AUTO MUTE indica or blinks once. A shor blink means he func ion has
been enabled. A long blink means he func ion has been disabled.
11.3 PA Mode
11.3.1 Mode Descrip ion
In his mode, received audio from selec ed radios will be ou pu hrough he
PA Speaker Ou pu . Keying he PTT will send Mic audio o he PA Speaker.
11.3.2 Selec ing PA Mode
In PA mode, he PA (green) indica or is li . If i 's no li , momen arily press
he PA/RPT bu on or he digi "9" on a DTMF microphone (if enabled) o
selec PA Mode.
11.3.3 Using PA Mode
Selec any radio(s) o be sen o he PA Speaker by momen arily pressing
any of he RAD1-RAD4 bu on(s) or he corresponding digi s (1-4) on a
DTMF microphone (if enabled). To make a PA announcemen , key he PTT
and speak in o he microphone.
The SEL/PA Volume Con rol con rols he PA volume.
11. RPT Mode
11.4.1 RPT Mode Descrip ion
In his mode, received audio from one radio is re ransmi ed hrough ano her
radio. Re ransmi ing is con rolled by ac iva ion of he Busy indica ors which
opera e by de ec ing received audio (VOX). If received audio is oo low in
volume, hese indica ors won' ligh and he RPT func ion won' work.
11.4.2 Selec ing RPT Mode
Press and hold he PA/RPT bu on or he digi "9" on a DTMF microphone (if
enabled) un il he RPT (red) indica or urns on.
11.4.3 Using RPT Mode
Any number of radios can be selec ed a he same ime in RPT Mode. To
selec a radio, momen arily press he bu on or he corresponding digi (1-4)
on a DTMF microphone (if enabled) for he desired radio(s).
Unless he COR Op ion is ins alled, RPT opera ion is VOX-based. When
RPT Mode is on, an audio level ha is sufficien o ligh a radio's Busy
indica or will key he PTT for he o her Selec ed radio(s) and re ransmi
received audio.
NCS-C250C Instruction Manual Rev J Copyright © 2004-2010 New Communications Solutions, LLC
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When in RPT Mode, keying he Mic's PTT causes all selec ed radios o
ransmi microphone audio. This can be used for ransmi ing on mul iple
radios simul aneously where legal and appropria e.
11.5 Additional Functions
11.5.1 Wa chdog Timers
Each Radio's PTT incorpora es a Wa chdog Timer ha disables a Radio's
PTT af er 3 minu es of con inuous ransmission. To rese he Wa chdog
Timer and resume ransmission, PTT mus be released briefly. In RPT
Mode, he received signal being re ransmi ed mus s op briefly. The
Wa chdog Timer also rese s au oma ically af er 30 seconds even if PTT is
s ill keyed or he received signal has no s opped. This is helpful in he even
of a radio problem or o her malfunc ion.
11.5.2 Fron Panel Dimmer
The brigh ness of he fron panel indica or LEDs is con rolled by a pho ocell
loca ed in he fron panel. This provides indica ors ha are no oo brigh in a
dark environmen bu can s ill be seen in a brigh environmen .
12.0 C250C Option Board
The NCS-C250C is available wi h he following fea ures provided by he Fac ory Ins alled Op ion
Board:
•COR (Carrier Opera ed Relay)
This op ion causes he Busy Ligh s and he Repea er func ion o be con rolled by digi al Busy
signals from he radios. The sense of he busy signals from he radios is selec able ei her
"High = Busy" or "Low = Busy".
When he COR Op ion is ins alled, VOX opera ion of he Busy Ligh s and Repea er Func ion
is disabled.
•Hookswi ch
This op ion allows a Hookswi ch or microphone "hang-up" signal o be sen from he
microphone hrough he C250C o he radios. In opera ion, he Hookswi ch line of all
Unselec ed radios is pulled "low". When a radio is selec ed, ha radio's Hookswi ch line is
released unless he microphone connec ed o he C250C is hung up on a grounded hook. In
his case he Hookswi ch line for he Selec ed Radio is pulled "low".
One example of use of his fea ure is o ac iva e radios' scan func ions. In his applica ion, all
radios scan con inuously. When he mic is lif ed off i s grounded hook, he Selec ed radio
s ops scanning. Scanning on he Selec ed radio resumes when he mic is placed back on i s
grounded hook.
NCS-C250C Instruction Manual Rev J Copyright © 2004-2010 New Communications Solutions, LLC
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