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   - PAC-RT and PAC-PL
     - PAC Introduction
     - PAC-PL Models
     - PAC-RT Models
     - PAC Manuals
     - PAC-PL Vehicle Repeater
     - PAC-RT Vehicle Repeater
     - PAC Cables
     - PAC Cable Wiring Pin Outs
     - PAC Cable Connector Parts List
       
   - HOME

 

[SYNTOR] [SYNTOR X] [SYNTOR X 9000 and X 9000E] [TRUNKING SYNTOR X and SYNTOR X 9000] [SPECTRA]

[PL] [DPL] [PAC-PL and PAC-RT VEHICLE REPEATERS] [HHCH] [PROM PROGRAMMERS] [POWER WIRING]

[GLOSSARY] [WEB LINKS] [SURPLUS PARTS GUIDE] [ITEMS FOR SALE] [WEB SITE REVISIONS] [CONTACT]

 

 

PAC Introduction:

Motorola uses the root terms PAC and Vehicle Repeater System (VRS) to identify their vehicle repeater systems. GE uses the term Extender for their vehicle repeater system. Motorola uses the term Extender for a Syntor X / Syntor X 9000 low band (29 to 54 MHz range) receiver noise canceling system which is entirely built into the low band radio drawer. When discussing Motorola equipment, remember the term Extender has nothing at all to do with vehicle repeater systems.

The PAC-PL and PAC-RT are vehicle repeater systems. These PAC systems allow a handheld radio to repeat to and from a vehicle's mobile radio (i.e. the handheld radio becomes a wireless remote speaker microphone for the mobile radio in the vehicle). This gives the radio operator the ability to operate the mobile radio when outside the vehicle. The PAC transmitter has a very low power output of about 250 milliwatts. The handheld radio should also be a low power radio (i.e. 2 watts or less). This is all that is needed to do the job when you are near your vehicle. The PAC systems are not intended to operate like a normal long range repeater and are not satisfactory for use as a regular repeater.

The PAC unit and handheld radio are on the same simplex frequency (i..e. the PAC and handheld receive & transmit frequencies are the same). This simplex frequency can not be in the same frequency band as the mobile radio. This means a VHF mobile radio must use a UHF PAC and a UHF mobile radio must us a VHF PAC. A low band or 800 MHz mobile can use either a VHF or a UHF PAC. This type of operation is called cross band repeat.

A PAC can be modified to operate in the same band as the mobile radio with the addition of external duplexers (i.e. same band repeat instead of cross band repeat). Even with duplexers, the PAC frequency must be far enough away from any mobile radio frequency to allow the duplexers to operate correctly. Many mobile duplexers, which usually run around the $ 1000 price range or higher new, require at least 1.5 MHz separation (depending on the power level of the mobile radio). High power mobiles may require an even larger frequency separation and might even require substituting much larger and more expensive filter cans that are not really suitable for mobile operation. Any external duplexer will cause both Tx and Rx signal loss to and from the PAC antenna. Additional modifications of the PAC itself may be required to overcome this signal loss if it compromises the PAC performance beyond what you are willing to tolerate.

The difference between the PAC-PL and PAC-RT is the PAC-RT has a priority resolution scheme to prevent multiple mobile transmitters from interfering with each other. If two or more PAC equipped vehicles that use the same handheld frequency and/or same mobile frequency were to be keyed up together by a handheld radio, the result would be that the radios on a common frequency would jam each other. This would result in a total mess and will prevent any communication. The same applies to the PAC unit transmitting to the handheld radios. Multiple vehicle based PAC units transmitting right next to each other on the same handheld radio frequency will jam each other and result in another mess. The PAC-RT priority resolution scheme will automatically shut down all but one PAC-RT unit when a bunch of them are parked near each other. An audible tone called a Singletone is used by the PAC-RT priority resolution scheme. The PAC-RT operating frequencies, PL tone and Singletone frequency must be setup correctly to work with each other.

The PAC-PL does not have this priority resolution scheme, so a PAC-PL system installed in multiple vehicles would need to have each PAC-PL unit and its handheld radio on a totally different simplex frequency to prevent interference between handheld radios. If the other PAC-PL units can not all hear the mobile radio frequency and repeat it to their handhelds, or if the handheld radios de-sense each others receivers, you would still have multiple mobile radios keying up on the same frequency (i.e. with all the handheld radios on different frequencies you can not hear someone else using their PAC-PL unless your setup is repeating the mobile frequency back to your handheld on its unique frequency). The need for multiple, unique, channel frequencies is why PAC-PL is not practical when you have multiple PAC-PL units using a common radio communications system in the field together.

If the vehicle with the priority PAC-RT unit at a scene with multiple vehicles, turns off their PAC-RT and leaves the scene, another active PAC-RT unit parked at the scene will automatically take over as the priority unit and continue to provide PAC-RT mobile repeating from one of the remaining vehicles.

The PAC-RT has a mobile detector option. This is only used when the base stations transmit on one frequency and all the mobiles transmit on a different frequency. For example; when the base transmits on 41.5 MHz and the vehicle transmits on 44.6 MHz, the PAC-RT can determine when the base is transmitting on 41.5 MHz through the vehicle radio, but this type of arrangement prevents the PAC-RT from hearing other mobile radios transmitting on 44.6 MHz, unless it has its own optional mobile detector listening to 44.6 MHz. Notice the 44.6 MHz mobile radios are not being repeated back on the 41.5 MHz base frequency. When using this type of operation, the PAC-RT priority resolution scheme needs to have a receiver tuned to the mobile radio frequency to listen for other nearby mobile units. This is what the mobile detector is, a multiple channel receiver tuned to the mobile radio transmit frequencies. The VHF PAC-RT can have up to 5 mobile detector frequencies and the UHF PAC-RT can have up to 4 mobile detector frequencies.

A PAC repeater uses crystals to set its simplex Rx and Tx operating frequencies and a Vibrasponder reed for the PL tone. In addition, the PAC-RT repeater uses a Vibrasponder reed to generate the priority resolution audio frequency Singletone. The PAC-PL DPL is selected with a special plug in SIP. The PAC units do not have a microprocessor, instead they use hard wired discrete logic chips. Because of this, they are not programmable at all and there is no software or RSS for them. However, even though PAC units can not be programmed, they can be custom configured by changing internal connections and jumpers to enable or disable some features / functions.

The PAC units can have an on/off switch hooked to the charger pocket of a handheld radio Convert-a-com. This is used to automatically turn on the PAC unit when the handheld is removed from the vehicles charger pocket. They can also have an external on/off toggle switch for manual operation. The PAC units were originally intended to be used with MX310, HT220, Handie-Talkie or Handie-Com handheld radios (i.e. the accessory cable connector intended for the vehicle's handheld radio charger pocket on/off switch may need modification for newer model charger pockets).

The PAC unit is connected to the mobile radio receiver's raw unsquelched detected audio output. The PAC has its own internal squelch circuit fed by the mobile radio's detected audio that triggers the PAC transmitter. So, no separate Carrier Operated Relay (COR) control line is required from the mobile radio to activate the PAC transmitter. Design features like this have made the PAC unit interface so straight forward and simple that it even works with some GE and RCA radios.

The PAC units have a circuit that will allow the handheld radio to force the PAC to transmit through to the mobile radio. This is useful when distant signals are interfering with your mobile receiver and causing the PAC unit to transmit this interference to your handheld radio. Normally the handheld PTT would be useless because the PAC would be busy retransmitting from the mobile to the handheld, not listening for the handheld radio. However, every few seconds or so, the PAC will interrupt its transmission to the handheld and check to see if a handheld radio is transmitting. If a handheld radio is found transmitting with the correct PL or DPL, the PAC will ignore the mobile receiver and transmit from the handheld to the mobile radio frequency. This circuit is called the Portable Priority Interrupt.

The Portable Priority Interrupt is a great feature when it is used properly. Preventing unintentional misuse of this feature is a good reason to use PL or DPL on your handheld radio transmissions. If something puts an unwanted interference signal on the handheld frequency, the PAC will key the mobile radio unless you have PL or DPL decoding on the PAC handheld frequency to screen out the interference. The Portable Priority Interrupt will ensure the PAC can key up the mobile even when there is already legitimate communications on the mobile radio frequency, which will cause illegal and harmful interference to other radios. Since the mobile radios usually are high power, this interference can be very serious, making the use of PAC PL or DPL more than worth the effort. If you have the PAC-RT without PL or have disabled the PAC PL or DPL, you should disable the Portable Priority Interrupt feature (you still need to deal with handheld frequency interference as the mobile radio will still key up, but at least it will not automatically key up on top of another mobile radio station).

The PAC units were designed to interface with older mobile radios that only had 4 frequencies maximum and used special control heads to cause the mobile radio to scan by sequentially activating 1 of 4 frequency select lines. The original Syntor radio is only truly compatible when it is used as a 4 frequency radio. The Syntor X would have to be configured as a 4 frequency control head to work with the PAC-RT optional multiple frequency Mobile Detector capability. The Syntor X will not work with the PAC-PL scan options. The Syntor X 9000 and Spectra will not work with the PAC-RT optional multiple frequency Mobile Detector capability or the PAC-PL scan options. The PAC units will still function, although the PAC may work as if it thinks it is hooked to a single frequency mobile radio. There is always the possibility of home made custom interface hardware or custom control panel to recover some of the PAC-RT optional multiple frequency Mobile Detector capability or the PAC-PL scan options functionality.

The PAC units have a built in 2 minute transmitter time out timer. The PAC-PL times both mobile to handheld and handed to mobile transmit times. The PAC-RT timeout timer can be custom configured or disabled. A note in the manual said the timeout timer should never be disabled if PL or DPL is not used. I guess it is possible the FCC required/requires a PL or DPL signal to control the PAC if there is no working time out timer in the PAC?

The PAC-RT units are only intended to be used while the vehicle and its mobile radio is stationary. Turning it on in a moving vehicle can cause lots of unpredictable priority resolution function problems for yourself and other PAC-RT equipped vehicles. Besides, it makes no sense to use any of the PAC units when you have direct access to the mobile radio from inside the vehicle.

Many of the PAC features can be defeated by modifying the PAC circuits. For example: the PAC-RT Singletone can be turned off and the Portable Priority Interrupt can be turned off. The manuals have details on how to perform these modifications.

The PAC vehicle repeater product line has had a remarkably long life span and they work with all the conventional Syntor, Syntor X, Syntor X 9000 and Spectra radios. This is why they get their own page. The Syntor X 9000 introduced an improved Vehicle Repeater System (VRS) that is also used by the Spectra. The VRS has a priority resolution scheme that works with other PAC-RT equipped vehicles (i.e. only the priority resolution scheme is compatible, the PAC-RT and VRS hardware is not interchangeable), it is programmable and added more features, but it is still uses crystals to set its operating frequency. The VRS uses the mobile radio itself as the mobile detector (if you enable the option), so the VRS mobile detector is not limited to 4 or 5 channels like the PAC-RT. The newer VRS will only work with Systems 9000 radios (i.e. like the Syntor X 9000 and Spectra radios) and requires RSS to program it. Here is the Syntor X 9000 VRS model chart, Syntor X 9000 VRS Programming Notes and the Spectra VRS model chart.

There is an interface modification for connecting a PAC to the Syntor X 9000 radio (it uses the radio cable "Spare 1" line and hooks it to the PAC "PTT IN" pin) that I do not have any information on. It might possibly be as simple as opening the Systems 9000 control head and hooking a wire from the microphone PTT input to the Spare 1 pin? This should allow the PAC to repeat any transmissions made from the mobile radio microphone inside the vehicle to the handheld radio.

The Systems 9000 VRS also has an optional feature called mode steering. The RSS is programmed such that one of 4 valid detected PL tones (sent to the VRS by the handheld radio) can steer the mobile radio to a preprogrammed mode or to the current selected mode (i.e. the handheld radio remotely selects a new frequency on the mobile radio). You can RSS program the VRS not to use mode steering or to have up to 4 mode steering selections. The mobile radio mode steering can be temporary (just for the duration of the VRS repeat) or you can set the mobile to latch onto the steered mode and remain there after the VRS repeat is done.

There is a report of a SP version of the H14TTY3110A PAC-RT units that will do channel steering. The NLN4358A logic board is replaced by NLN4358A-SP7 and PLN1005 Steering logic with lockout is added. These will steer four channels. There are also PAC-TR and PAC-TL trunking units that can steer up to 20 talkgroups. I do not have any other information on these SP units at this time.

Some people have been removing the original crystal controlled radio circuit board from the PAC and replacing it with a modern synthesized radio. If you do this, realize that internally the PAC operates at a regulated + 10.5 volts, which is also supplied to the original radio circuit board through its antenna connections. You will have to make sure the replacement radio does not draw too much current (i.e. more than the original radio circuit board) and can operate at 10.5 volts. If not, you will have to add a custom power regulator to run the replacement radio. Experience is required to do this type of this conversion and having the manual is also very important.

Setting up PAC or VRS units can be tricky and is not always easy. One of the most important things is getting as much physical separation between the mobile and PAC or VRS antennas as possible.

 

 

PAC-PL MODEL NUMBER INFORMATION

 

MODEL NUMBER

 

DESCRIPTION
 H13RPY3110A  VHF, PL
 H13RPY6110A  VHF, DPL
 H14RPY3110A  UHF, PL
 H14RPY6110A  UHF, DPL

 

 

PAC-RT MODEL NUMBER INFORMATION

 

MODEL NUMBER

 

DESCRIPTION
 H13TTY3110A  VHF, PL
 Z13TTY3120A  VHF, 2 Frequency, PL
 H14TTY3110A  UHF, PL

 

 

PAC Manuals
Part # Description Price
 68P81014C55  PAC-PL Operating Instructions NLA 
 68P81014C50  PAC-PL Repeater Theory & Maintenance, Superceded by 68P81033C95 NLA 
 68P81033C95  PAC-PL Repeater Theory & Maintenance 12.00 
 68P81102C03  Control Unit/Vehicular Charger or Radio Holder Section 2.45 
 68P81014C51  PAC-PL Repeater, H13RPY3110A, Early Version Manual, VHF 4.50 
 68P81033C85  PAC-PL Repeater, H13RPY3110A, H13RPY6110A, B Model, VHF 46.00 
 68P81014C52  PAC-PL Repeater, H14RPY3110A, Early Version Manual, UHF NLA 
 68P81033C90  PAC-PL Repeater, H14RPY3110A, H14RPY6110A, B Model, UHF 27.00 
 68P81009C95  PAC-RT Operating Instructions 1.25 
 68P81010C20  PAC-RT Repeater Theory & Maintenance, Superceded by 68P81010C05 5.75 
 68P81010C05  PAC-RT Repeater Theory & Maintenance NLA 
 68P81102C03  Control Unit/Vehicular Charger or Radio Holder Section 2.45 
 68P81019C65  NRD6632A Mobile Detector Cables & Control Unit Charger, Supplement NLA 
 68P81010C06  PAC-RT Repeater, H13TTY3110A, VHF 23.00 
 FMR-1523-1  GE Delta SX, Syntor X, Syntor X 9000 Cables and Parts Lists Supplement -
 68P81013C95  PAC-RT Repeater, Z13TTY3120A, 2 Frequency, VHF 21.75 
 68P81010C09  PAC-RT Repeater, H14TTY3110A, UHF NLA 
 FMR-1525-1  GE Delta SX, Syntor X, Syntor X 9000 Cables and Parts Lists Supplement -

 

PAC-PL Vehicle Repeater:

NLN4942B - Main Interface Board, PL
NLN5097B - Main Interface Board, DPL
NUD6022BB - VHF Transceiver Board (later Version)
NUE6252B - UHF Transceiver Board (later Version)
KNX1013B - Transmitter Resonator .0005% Stability (standard for UHF)
KNX1014A - Transmitter Resonator .002% Stability (standard for VHF)
H567 - Option, .0005% Transmitter Frequency Stability (VHF 150.8-174 MHz Only)
H820 - Option, PL Generator
H928AB - Option, VHF Scan Mute (uses NLN4943A)
H928AC - Option, UHF DPL Scan Mute (uses NLN4963A)
H930 - Option, Auto-Monitor

 

PAC-RT Vehicle Repeater:

NLN4385A - Logic Board without PL
NLN8982A - Logic Board with PL
NUD6022AB - VHF Transceiver Board (early Version)
NUD6022BB - VHF Transceiver Board (later Version)
NUE6252A - UHF Transceiver Board (early Version)
NUE6252B - UHF Transceiver Board (later Version)
KNX1013B - Transmitter Resonator .0005% Stability (standard for UHF)
KNX1014A - Transmitter Resonator .002% Stability (standard for VHF)
NRB6252A - Mobile Detector Board (30.00-39.99 MHz)
NRB6262A - Mobile Detector Board (40.00-50.00 MHz)
CNRD6492A - Mobile Detector Board (VHF 150.8-174 MHz)
NRE6191A - Mobile Detector Board (450-470 MHz)
NRE6192A - Mobile Detector Board (470-480 MHz)
NRE6193A - Mobile Detector Board (480-512 MHz)
H563 - Option, I.F. Injection High Side
H564 - Option, I.F. Injection Low Side
H567 - Option, .0005% Frequency Stability (VHF 150.8-174 MHz Only)
H805 - Option, Mobile PL Decoder
H811 - Option, Channel 1 PL Disable (requires H805)
H812 - Option, Channel 2 PL Disable (requires H805)
H813 - Option, Channel 3 PL Disable (requires H805)
H814 - Option, Channel 4 PL Disable (requires H805)
H826 - Option, Mobile PL Detector
H911AA - Option, Mobile Detector for 1 Frequency (30-50 MHz)
H912AA - Option, Mobile Detector for 2 Frequency (30-50 MHz)
H913AA - Option, Mobile Detector for 3 Frequency (30-50 MHz)
H914AA - Option, Mobile Detector for 4 Frequency (30-50 MHz)
H911AB - Option, Mobile Detector for 1 Frequency (150.8-174 MHz)
H912AB - Option, Mobile Detector for 2 Frequency (150.8-174 MHz)
H913AB - Option, Mobile Detector for 3 Frequency (150.8-174 MHz)
H914AB - Option, Mobile Detector for 4 Frequency (150.8-174 MHz)
H911AC - Option, Mobile Detector for 1 Frequency (450-512 MHz)
H912AC - Option, Mobile Detector for 2 Frequency (450-512 MHz)
H913AC - Option, Mobile Detector for 3 Frequency (450-512 MHz)
H914AC - Option, Mobile Detector for 4 Frequency (450-512 MHz)
H928AB - Option, Scan Mute
H928AC - Option, DPL Scan Mute
H937 - Option, Base Repeater

 

PAC-PL and PAC-RT Cables:

NKN6212A - Inteface Cable (12 Frequency Multi-frequency Micor)
NKN6214A - Interface Cable (Mocom 70, Motrac, Motran, Mitrek)
NKN6214BSP09 - Interface Cable (MaraTrac)
NKN6231A - Interface Cable (GE Mastr Progress Line)
NKN6232A - Interface Cable (GE Mastr II)
NKN6233A - Interface Cable (RCA Series 1000 / 700 / 500)
NKN6250A - Interface Cable (Maxar)
NKN6313A - Interface Cable (Syntor)
NKN6314A - Interface Cable (Syntor X)
NKN6371A - Interface Cable (Syntor X 9000)
NKN6372A - Interface Cable (Trunked Syntor X 9000)
NKN6374A - Interface Cable (GE Delta SX)
NKN6375A - Interface Cable, NKN6314A Replacement (Syntor X)
NKN6442A - Interface Cable (Spectra)

 

PAC Cable Wiring Pin Outs:

Hand Held Radio Charger Connector (Negative Ground)
Charger
Pin #
 Wire Color PAC
Pin #
 PAC Pin Description
1  Red 2
16
 B+
 Mobile On/Off
2  Yellow 15  Port In/Out
3  Orange 3  Spare
4  Brown 9  PAC On/Off
5  Green 4  Spare
6  Black 22  Ground

Syntor X NKN6314A Cable Pin Out (Negative Ground)
Radio Adaptor Box
PAC
Pin #
 PAC Pin Description Radio
T-Cable
J1 Pin #
 Radio Pin Description
A  N/C    

B
 N/C    
1  B+ 15  Switched B+
2  B+ (jumpered to pin 16)    
3  Spare    
4  Spare    
5  Spare    
6  PTT Out 4  PTT (Input)
7  F5 12  Mode 5
8  Ground 10  B-
9  PAC On/Off    
10  PTT Return (jumpered to pin 17)    
11  F1 13  Mode 1
12  F2 17  Mode 2
13  F3 24  Mode 3
14  F4 25  Mode 4
15  Portable In/Out    
16  Mobile On/Off (jumpered to pin 2)    
17  Ground (jumpered to pin 10)    
18  Mic. Low 14  Mic. Low
19  Mic. Hi 27  Mic. Hi
20  PTT In 4  PTT
21  Mobile Disc. 2  Detected Audio
22  Ground    
23  Spare    
24  Spare    

Syntor X NKN6375A Cable Pin Out (Negative Ground)
Radio T-Cable
PAC
Pin #
 PAC Pin Description Radio
T-Cable
J1 Pin #
 Radio Pin Description
A  N/C    

B
 N/C    
1  B+ 15  Switched B+
2  B+ (jumpered to pin 16)    
3  Spare    
4  Spare    
5  Spare    
6  PTT Out 4  PTT (Input)
7  F5    
8  Ground 10  B-
9  PAC On/Off    
10  PTT Return (jumpered to pin 17)    
11  F1    
12  F2    
13  F3    
14  F4    
15  Portable In/Out    
16  Mobile On/Off (jumpered to pin 2)    
17  Ground (jumpered to pin 10)    
18  Mic. Low 14
10
 Mic. Low
 Chassis
19  Mic. Hi 27  Mic. Hi
20  PTT In    
21  Mobile Disc. 2  Detected Audio
22  Ground    
23  Spare    
24  Spare    

Syntor X 9000 NKN6371A Cable Pin Out (Negative Ground)
Systems 9000 Radio T-Cable
PAC
Pin #
 PAC Pin Description Radio
T-Cable
J1 Pin #
 Radio Pin Description
A  N/C    

B
 N/C    
1  B+ 6  Switched B+
2  B+ (jumpered to pin 16)    
3  Spare    
4  Spare    
5  Spare    
6  PTT Out 1  PTT (Input)
7  F5    
8  Ground 32  B-
9  PAC On/Off    
10  PTT Return (jumpered to pin 17)    
11  F1    
12  F2    
13  F3    
14  F4    
15  Portable In/Out    
16  Mobile On/Off (jumpered to pin 2)    
17  Ground (jumpered to pin 10)    
18  Mic. Low 14
2
 Mic. Low
 Detected Audio Shield
19  Mic. Hi 27  Mic. Hi
20  PTT In 24  Spare 1
21  Mobile Disc. 2  Detected Audio
22  Ground    
23  Spare    
24  Spare    

 

PAC-PL and PAC-RT Cable Connector Parts List:

03-00138901 - Screw, # 6-32 x 5/8" (3 req'd)
09-84086B01 - Housing (the pins go here)
09-84151B03 - Contact Pins (5 / package) $ 2.15 (9 req'd)
15-05572D01 - Front Housing
15-05573D01 - Rear Housing
28-84510H01 - 6 pin Connector (used on handheld charger pocket)
30-05635D01 - Cable, 17'
37-00842245 - Strain Relief
42-00850817 - Clamp

 

 

[SYNTOR] [SYNTOR X] [SYNTOR X 9000 and X 9000E] [TRUNKING SYNTOR X and SYNTOR X 9000] [SPECTRA]

[PL] [DPL] [PAC-PL and PAC-RT VEHICLE REPEATERS] [HHCH] [PROM PROGRAMMERS] [POWER WIRING]

[GLOSSARY] [WEB LINKS] [SURPLUS PARTS GUIDE] [ITEMS FOR SALE] [WEB SITE REVISIONS] [CONTACT]

[TOP] [HOME]

 

--

PL, Private Line, DPL, Digital Private Line, Vibrasponder, MPL, Talkaround, MDC-600, MDC-1200, MVS-20, Securenet, Smartnet, Privacy Plus, Trunked X2, Trunked X3, Touch Code, Quick Call II, Channel Scan, Talkback Scan, System 90, System 90*s, Systems 9000, PAC, PAC-PL, PAC-RT, PAC-TR, PAC-TL, MX-310, HT220, Mitrek, Micor, Spectra, MataTrac, Syntor, Syntor X, Syntor X 9000 and Syntor X 9000E are trademarks of Motorola Inc.