Understanding Leaky Feeder Systems

Understanding Leaky Feeder Systems
MCA VHF the leaky feeder people® Copyright MineCom 2005

The information contained in this document has been provided to the original addressee as “Commercial in Confidence” and therefore is NOT for general release without prior approval of MineCom Copyright MineCom 2005

MCA1000 SMARTAmp SMARTCAM RINGFeeder SMARTTune SMARTControl
The following names are registered brand names of MineCom Australia Pty. Ltd. MCA1000 SMARTAmp SMARTCAM RINGFeeder SMARTTune SMARTControl Copyright MineCom 2005

don’t just manufacture ONE communications backbone, they produce an
MineCom don’t just manufacture ONE communications backbone, they produce an E x t e n d e d r a n g e of communications SOLUTIONS Copyright MineCom 2005

MineCom offer Integrated Communications Solutions for Mining
Two Way Radio Data Video Leaky Feeder systems Fibre Optics Tracking Train Control Gas Monitoring Automation Copyright MineCom 2005

Contents Understanding leaky feeder cables
Understanding the head end equipment Understanding the distribution equipment What information is required from the customer What makes up the MCA1000 Copyright MineCom 2005

Communicating in an underground tunnel environment is difficult, but possible.
Copyright MineCom 2005

However it is a precise technology, therefore you MUST be prepared to follow the strict system design guidelines if the system is to work as it was designed. Copyright MineCom 2005

MCA1000 VHF Copyright MineCom 2005

Understanding leaky feeder cables
System Guidelines Step ONE Understanding leaky feeder cables Copyright MineCom 2005

People commonly refer to it as a ‘Leaky Feeder Cable’ ………
People commonly refer to it as a ‘Leaky Feeder Cable’ ……….because this name best describes what it does. Copyright MineCom 2005

However the correct terminology is a – ‘Distributed Antenna System’
As it is really one BIG LONG Antenna and the RF signals are distributed evenly along its length. Copyright MineCom 2005

Over the last 35 years the ‘leaky feeder’ based backbone has proven to be the most reliable form of communications in confined spaces. Other forms, or methods of communications have come and gone in that time Copyright MineCom 2005

ore trucks, loaders etc, reflect/deflect or block the radio signals
Some people still try to use above ground style antennas in an underground environment, however they are - expensive easily damaged corrode quickly subject to phasing ore trucks, loaders etc, reflect/deflect or block the radio signals Copyright MineCom 2005

Standard Antenna’s Strong signal No signals Copyright MineCom 2005

Leaky Feeder Strong signal No signals Copyright MineCom 2005

A Leaky Feeder cable is similar to a garden watering system…..

Pump …where you run a plastic hose pipe around the garden with holes in it, to water the plants. Farmers have to use a pump, to ‘boost’ the water pressure, to compensate for the losses caused by the longer runs of water pipe required Copyright MineCom 2005

Normal coax cable is designed to pass RF signals from one end to the other with varying degrees of losses, dependant on the quality. The purpose of the outer copper shield, is to - keep as much signal as possible inside the cable and….. to prevent external RF signals and/or interference from entering into the cable Copyright MineCom 2005

the RF signals can be picked up by portable radios nearby
The external copper shield on a leaky feeder cable has ‘holes’ or ‘gaps’ in the shielding, designed to allow the RF signals running down it, to leak out evenly along its length the RF signals can be picked up by portable radios nearby Copyright MineCom 2005

The ‘holes’ in the leaky feeder cable also enables external RF signals (including interference) to enter into and run along the cable. Copyright MineCom 2005

Other aspects that govern the off-air coverage from leaky feeder cables -
Configuration of the outer shield – i.e. individual copper strands or a copper tube with holes drilled in it - will have an effect the level of signal leakage in/out of the cable Cable size Smaller diameter cable – higher signal losses, more amplifiers/gain required Larger diameter cable - less signal losses, less amplifiers/gain required Frequencies used Low frequencies – less signal losses, along the cable LESS amplifiers/gain required High frequencies - higher signal losses along the cable, MORE amplifiers/gain required Cable losses Cable losses vary dependant on - frequency used, diameter of the copper conductors, dielectric material utilised, quality/precision of the cable manufacturing machinery used, level of QA testing during manufacture process Copyright MineCom 2005

Other considerations that SHOULD be taken into account when using leaky feeder cables in tunnels -
Cable construction – Special Handling – All LF cables due to their design/construction require careful handling, some versions more than others Bending Radius - most LF cables have a very limited bending radius, i.e. 400mm to 1000mm diameter. A few LF cables have been specifically designed for mine tunnel use and have a bending radius of 100mm. A damaged cable means increased losses, more amplifiers, increased cost Fire retardant – Only cables with a self extinguishing sheath should be used in mines and tunnel systems Halogen free – some brands of LF cables are manufactured using Halogen Free (Low-smoke) materials at an additional cost Foam filled – LF cables using a foam dielectric, will prevent water entering the cable and running down the cable into amplifiers/devices Copyright MineCom 2005

The method of installation in the tunnel is also an important consideration -
Cable installation - Cable mounting – LF cables with a corrugated copper tube (shield) with ‘slots’ in it, MUST to be suspended at least 100mm BELOW a catenary cable to ensure reasonable coverage in the tunnel. VHF Band - LF Cables designed specifically for mine use, can be strapped directly on to water pipes, air pipes, low voltage power cables Corrugated style LF cables must be 1 meter intervals. LF cables designed for mine use must be 3 meter intervals in the horizontal plane, 2 meter intervals in the vertical plane Cable Location – LF cables must be ‘seen’ by the naked eye and not hidden away behind pipes, or buried under other cables in a cable tray LF cables should be located where they are least likely to be damaged hit i.e. hit by passing trucks and loaders etc Copyright MineCom 2005

Outer copper tube (shield) with slots or holes in it
To recap – Corrugated leaky feeder cables do have lower losses and therefore require less amplifiers……BUT They are less flexible and therefore more prone to damage during installation as well as during normal day to day mine operations They are more expensive AND they require specialised mounting hardware – ‘hangers’, connectors etc The RF signals leak out/in through a single row of ‘slots’ in the outer copper tube (shield) MineCom UHF Leaky Feeder Cable Outer sheath Outer copper tube (shield) with slots or holes in it Foam dielectric Center conductor Fire Retardant sheath Copyright MineCom 2005

Corrugated leaky feeder cables
100mm gap MUST be suspended at least 100mm below the catenary cable MUST be kept clear of any metallic surface to ensure that the RF signals can ‘leak out’, as the radiating holes in the shield are not marked and cannot be seen through the outer sheath Copyright MineCom 2005

The MineCom leaky feeder cable was designed specifically for use in mine tunnels and tunnel construction use Copyright MineCom 2005

AND it can be strapped directly onto – air and water pipes
It radiates 360 degrees AND it can be strapped directly onto – air and water pipes catenary cables low voltage power cables weld mesh rock bolts or under cable trays etc. Copyright MineCom 2005

It can be repaired in minutes - NO special tools are required
It is more flexible, easier to handle and less prone to damage, than corrugated forms of leaky feeder cables. It can be repaired in minutes NO special tools are required MineCom Leaky Feeder Cable VLFC Outer sheath Yellow or Blue Fire Retardant sheath 16 helical wound copper strands Foam dielectric Center conductor Copyright MineCom 2005

It is EASY to install, EASY to expand, EASY to repair, EASY to Maintain AND it is very COST effective Copyright MineCom 2005

AND it can be bent to 100mm diameter.
MineCom Leaky Feeder Cable MineCom Leaky Feeder Cable AND it can be bent to 100mm diameter. Copyright MineCom 2005

MineCom only use ‘foam dielectric’ cables because an air dielectric’ cable caused this damage to an in-line-amplifier Copyright MineCom 2005

Understanding the Head End equipment
System Guidelines Step Two Understanding the Head End equipment Copyright MineCom 2005

Head End Rack Location Performance Redundancy Safety Interconnection
The location (placing) of the rack enclosure will have a major bearing on system – Performance Redundancy Safety Interconnection Copyright MineCom 2005

Located on the Surface Safety < Interconnection < Redundancy =
Performance = Scene 1 - Head end rack located on the surface, with only a single leaky feeder cable running underground. IF the leaky feeder cable was damaged in the shaft, 95% of the communications system would be lost. Copyright MineCom 2005

Located Underground Safety < Redundancy < Performance <
Interconnection < Scene 2 – Whereas if the head end rack was centrally located underground, with 3 leaky feeder cable ports in use and the cable was damaged in the shaft, only 5% of the communications system would be lost. Copyright MineCom 2005

Where a mine generates Hazardous gases such as - Methane and/or Hydrogen as found in Coal mines (and some hard rock mines) then the Head End Rack MUST be located on the surface in a safe, NON Hazardous location. AND an IS barrier MUST be fitted between the Head End equipment and the leaky feeder cable(s). Copyright MineCom 2005

With humans, everything in our body is controlled by the BRAIN
With the MineCom everything is controlled from the Head End equipment rack Copyright MineCom 2005

The Head End rack can contain one or more of the following equipment -
MCA1000 Head End MCA1000 Diagnostic Head End Circuit Breaker Panel Voice Radio Base Stations Data Radio Modems Transmitter Isolators Master PLC SMARTAmp Head End SMARTVideo Video Demodulators Radio to Telephone Interface Audio Bridge Power Supply Battery Back Up Copyright MineCom 2005

Big mines – big racks Copyright MineCom 2005

Smaller mine - smaller rack/enclosures

To learn more about individual MCA1000 Head End Rack system components, please press an information button adjacent to the product name, press the BACK button to return to this page VHF Head End Standard VHF Head End RINGFeeder VHF Head End SMARTControl VHF Diagnostic Head End Modem Circuit Breaker Panel VHF Voice Radio Base Stations VHF Data Radio Modems VHF Transmitter Isolators VHF SMARTAmp Head End Modem VHF SMARTVideo Head End Demodulators Master PLC Copyright MineCom 2005

Other Head End rack equipment options offered –
Radio to Telephone Interface Audio Bridge Voice Enunciator Power Supply (Battery Back Up) Other Head End rack equipment options offered – Voice storage & Recording units Video TV Monitors Multi-media equipment Video & Quad Switchers PC’s for diagnostics/telemetry Copyright MineCom 2005

Understanding the Distribution equipment
System Guidelines Step Three Understanding the Distribution equipment Copyright MineCom 2005

SMART Products Amplifiers Joiners Terminations Branches

Maintaining a constant level of signal, along a long length of leaky feeder cable is no different to the requirement for a water pump, to maintain a reasonable flow of water along a water pipe. Copyright MineCom 2005

A leaky feeder cable is the most cost effective method of achieving reliable, good quality voice, data & video communications along a 10 kilometer mine tunnel Copyright MineCom 2005

In order to communicate along a 10 kilometer length of leaky feeder cable, RF signals 160MHz) need to be regenerated or ‘boosted’# many times over, to cover the whole 10Kms. # dependant on the signal losses of the leaky feeder cable used Copyright MineCom 2005

The MCA1000 mine based leaky feeder system, offers a cost effective solution –utilising small in-line, bi-directional amplifiers to boost the signals up and down the cable. 172 MHz 156 172 MHz 156 172 MHz 156 Copyright MineCom 2005

The distance between any two amplifiers is dependant on –
the cable losses at 172 Mhz (dB) the gain of the amplifier used whether one or more branch units are installed Up to 100 kilometers of leaky feeder cable can be connected to a single MCA1000 Head End. 172 MHz 156 172 MHz 156 172 MHz 156 <500 meters <500 meters Copyright MineCom 2005

There are many different types of leaky feeder cable available on the market.
It MUST be remembered that the leaky feeder cable is a Critical item governing the design of the system Cable losses + Branch losses + Joiner losses = ‘y’ Amplifier gain = ‘x’ ‘x’ MUST ALWAYS be greater than ‘y’ IF THE SYSTEM IS TO WORK Copyright MineCom 2005

Basic System Diagram TX RX TX RX TX RX Head End 500m 50m 350m 105m
172 MHz 156 172 MHz 156 50m Branch 1 350m 105m 172 MHz 156 350m 260m Terminator Branch 2 260m 500m 172 Mhz 156 Teminator 260m 500m Terminator Terminator Copyright MineCom 2005

Connection of the MCA1000 leaky feeder cable to amplifiers, branches, terminations etc is quick and easy with no special tools required. The connectors are designed to – * pass RF frequencies with minimum losses * pass DC voltages up to amps * provide strain relief Copyright MineCom 2005

Amplifiers MineCom do not manufacture just one model of VHF amplifier, they manufacture different models with 15 variants SEVEN Copyright MineCom 2005

VHF - VMLA VHF – VMLAD VHF - SMARTTune VHF – VLAV VHF - VLAVD
To learn more about individual MCA1000 Amplifiers press an information button below Press the BACK button to return to this page VHF - VMLA VHF – VMLAD VHF - SMARTTune VHF – VLAV VHF - VLAVD VHF – VLAV-IS VHF – VWACA Copyright MineCom 2005

Other Devices MineCom manufacture a range of passive devices that complement the systems operation

VHF – VTB Termination Box VHF – VJB Joiner Box
To learn more about individual MCA1000 Amplifiers press an information button below Press the BACK button to return to this page VHF – VBU1 Branch single VHF – VBU2 Branch dual VHF – VTB Termination Box VHF – VJB Joiner Box VHF - VJB-ANT In-Line Antenna VHF – VBU1-ANT In-Line Antenna VHF – VVAU In-Line Attenuator VHF – VVBU1 Video Branch single VHF – VPC Power Coupler Unit Copyright MineCom 2005

What information is required from the customer?
System Guidelines Step FOUR What information is required from the customer? Copyright MineCom 2005

BEFORE we can provide you with a firm quotation for an MineCom1000 for your mine or tunnel, we need some information from you…. Copyright MineCom 2005

STEP 1. You must a) Provide a current drawing or a sketch of the mine tunnel layout. b) The drawing MUST display ALL distances in METRES. c) The drawing MUST display all locations where AC mains power is available i.e. 110VAC, 220VAC, or 240VAC d) What type of mine is it, what commodity is extracted??? Copyright MineCom 2005

Basic Tunnel Sketch Your sketch does not need to be to scale, as long as your distance measurements are accurate Surface 550m 455m 260m 760m 850m 240VAC power Copper Mine Copyright MineCom 2005

STEP 2. From your sketch we will produce a system drawing. The system drawing will give us the quantity of devices etc required, which will enable us to produce a quotation. Copyright MineCom 2005

MCA1000 System Diagram Head End TX RX 500m 50m 350m 105m 260m Branch 1
172 MHz 156 Mhz Teminator Terminator 500m 50m 350m 105m 260m Copyright MineCom 2005

STEP 3. We also need a ‘Shopping list’, that will tell us the additional equipment that you require for your communications project. Copyright MineCom 2005

Jordan Mine Company SHOPPING LIST.
4 x Voice channels 1 x Data channels 3 x Video channels Telemetry outstations 4 x SMARTAmp telemetry units Video outstations 3 x SMARTCam cameras Voice radios – 10 x Handheld 8 x Vehicle (light – 4WD) 2 x Heavy duty waterproof for Loader 5 x Heavy duty for Haul truck 2 x Office desktop Mini-base Telephone connection – 1 x Radio to Telephone Interface System PC based Diagnostics 4 x Outstations Copyright MineCom 2005

STEP 4. From this information we can produce a quotation, which will be in the form of a spreadsheet and split into a number of sub-sections i.e.- + Head End equipment + Surface coverage + Underground devices + Video coverage + Telemetry coverage + Radio equipment + Spares etc. + Total System Cost Copyright MineCom 2005

Sample Only If you point and ‘Click’ on a hyperlink, this will take you to another page providing additional information on the product. Copyright MineCom 2005

ADD ON’s MineCom can offer you a whole range of ADD ON peripheral equipment that will enhance your MCA1000 leaky feeder system. Copyright MineCom 2005

Telemetry SCADA PLC’s Video Radio Data Modems Traffic Management Cage & Skip Automation Personnel & Vehicle Tracking Copyright MineCom 2005

Email:- sales@minecom.com WEB:- HTTP://www.minecom.com
53 Don Road, Devonport 7310 Tasmania Australia Tel: Fax: - WEB:- Copyright MineCom 2005

VHF Head End The standard MCA1000 leaky Feeder Head End sub rack combines the RF in/out ports of up to eight (8) voice and data base station repeaters, with up to four (4) leaky feeder output ports Voice Data Video next Copyright MineCom 2005

VHF Head End The standard MCA1000 Head End features include –
Expandable up to its full capacity of 32 channels (TX/RX) Voice – Data – Video ready FM re-broadcast transmission capable Full duplex operation minimum 15Mhz separation between TX and RX Diagnostics capable on board system metering, isolate individual leaky feeder output ports switchable in/out 19 inch rack mountable Copyright MineCom 2005

VHF RINGFeeder Head End
The MCA1000 RINGFeeder Head End sub rack combines the RF in/out ports of up to eight (8) voice and data base station repeaters, with up to four (4) leaky feeder output ports, PLUS the return RINGFeeder cable port. Voice Voice TX Isolator RX Leaky Feeder Ports P P P P4 MCA1000 Head End RINGFeeder Data Video RINGFeeder next Copyright MineCom 2005

VHF RINGFeeder Head End
If the cable breaks, you can still talk on…… ……………BOTH SIDES OF THE CABLE BREAK. Copyright MineCom 2005

VHF SMARTControl Head End
The MCA1000 SMARTControl Head End sub rack is designed to work with MineCom’s SMARTTune amplifiers. The SMARTControl head end provides a constant output signal level whether 1 or all 32 base transmitters are transmitting at the same time. Voice Data Video SMARTControl next Copyright MineCom 2005

A system design drawing is a MUST when using the standard range of mine leaky feeder amplifiers. Their design requires that the distance between any two amplifiers is fixed, not variable (based on cable/branch losses VERSUS amplifier gain, +/- 10%). 500m 200m 200m 172 MHz 156 172 MHz 156 172 MHz 156 Branch 1 next Copyright MineCom 2005

The SMARTControl head end provides a fixed reference (output) level that enables SMARTTune amplifiers to automatically adjust output gain, to compensate for the aggregate losses between the two amplifiers. 172 MHz 156 172 MHz 156 172 MHz 156 500m 400m 300m 200m 100m Copyright MineCom 2005

VHF Diagnostic Head End Modem
The MCA1000 Diagnostic Head End sub rack provides the interface between the remote VLAVD Diagnostic amplifiers and the Diagnostics PC next Copyright MineCom 2005

VHF Diagnostics Head End
The Diagnostic Head End RF modem – communicates with diagnostic equipped down line amplifiers to monitor system operation monitors amplifier, power coupler - RF levels – Volts - Current – AC Fail provides an RS232 serial port to communicate with a PC or PLC 19 inch rack mountable MCA1000 Diagnostics Modem Copyright MineCom 2005

Circuit Breaker Panel The MCA1000 Circuit Breaker panel has a dual role – a) as a re-settable circuit breaker in case of equipment failure b) enables the mines maintenance staff to quickly and easily isolate the DC supply to any item of powered equipment within the head end rack enclosure Copyright MineCom 2005

VHF Voice Radio Repeaters
‘Talk-through-repeaters’ are required to provide person to person mine wide voice communications. The MCA1000 provides full duplex operation, therefore separate base radio transmitters and receivers are required to plug into the head end. As there are no ‘off-the-shelf’ duplex handheld or vehicle radios available, 2 frequency simplex versions are used, with PTT (push-to-talk) operation. next Copyright MineCom 2005

MineCom recommends the use of modular plug in base station transmitters and receivers. They can be replaced by maintenance staff in minutes & automatically set themselves to the correct channel frequency for that TX or RX slot. next Copyright MineCom 2005

Lower cost one piece ‘talk-through-repeater’ base stations and mini repeaters are available for smaller budgets. Copyright MineCom 2005

VHF Data Radio Modem The base data radio modem must also utilise separate transmitters and receivers with the transmitter power limited to 2 watts max. MineCom offers both half duplex and full duplex data radio modems with data speeds from 1200baud up to 19.2kbps on VHF hi-band frequencies. MCA1000 Data Radio Modem next Copyright MineCom 2005

VHF Data Radio Modem Radio modems can be used to link PLC’s, PC’s, or just about any piece of electronic equipment that has an RS232 or RS485 port. Copyright MineCom 2005

VHF Transmitter Isolators
The MCA1000 is Data ready, so every precaution is taken to ensure that no stray RF gets back into another transmitter, voice or data. The TX isolator is like a non return valve, it prevents RF from another transmitter, getting into another transmitter. next Copyright MineCom 2005

VHF Transmitter Isolators

VHF SMARTAmp Head End Radio Modem
The VHF SMARTAmp Head End sub rack provides the interface between the remote SMARTAmp amplifiers and a PC next Copyright MineCom 2005

SMARTAmp radio modem – Communicates via the head end with remote inline SMARTAmp devices installed around the mine Communicates via a RS232 serial port with a PC or PLC (software available for both) 19 inch rack mountable MCA1000 SMARTAmp Modem Copyright MineCom 2005

VHF SMARTVideo Head End Demodulator
The VHF SMARTVideo Head End sub rack and plug in Demodulator cards provide the interface between the remote SMARTVideo cameras and the Video Monitor/TV next Copyright MineCom 2005

VHF SMARTVideo Head End Demodulator
The VHF SMARTVideo Head End sub rack will accept up to 16 plug in demodulator cards, each pre-programmed for a different frequency with a video level output to a video monitor. Copyright MineCom 2005

Master PLC Mine Com uses and recommends Allan Bradley PLC’s, due their compatibility with MineCom’s data radio modems and ready to use software for its Shaft Automation, Truck Loader, Traffic Management, SCADA and Telemetry systems next Copyright MineCom 2005

Master PLC MineCom can either modify existing software or commission new software to suit a customers individual requirements Copyright MineCom 2005

Radio to Telephone Interface
This device provides the wiring interface between a voice radio repeater channel and a PABX extension OR outside telephone line (PSTN) next Copyright MineCom 2005

Radio to Telephone Interface
The interface enables handheld portables and vehicle radios on that channel to receive telephone initiated calls any PABX extension at the mine. Radios equipped with a DTMF keypad, can initiate telephone calls with any PABX extension, or if permitted, dial an outside telephone number. Any radio can dial a pre-stored Emergency telephone number by pressing the PTT button 4 times in quick succession. 19 inch rack mountable Copyright MineCom 2005

Audio Bridge The Audio Bridge is similar in functions to a PABX system, i.e. connects one telephone extension to one or more other extensions. With an Audio Bridge, the audio wires from each Transmitter & Receiver are wired into the Audio Bridge. The Audio Bridge is programmed to interlink the audio feeds of two or more of the voice repeaters, when activated by a remote wireless command or manually operated at the Head End Rack. next Copyright MineCom 2005

Audio Bridge In an Emergency situation, some or ALL Voice channels TX/RX audio lines can be bridged or linked together (similar to a conference call on a PABX) to reduce confusion during an Emergency – ‘what channel do I switch to in an emergency’??? Transmit – 15 minute Blast warnings, Safety messages, all channel Page call When used in conjunction with a Voice Enunciator, stored voice messages can be transmitted to maintenance staff over all OR specific voice channels i.e. ‘Pump station 3 low water alarm’ The Mine Safety Officer can activate & deactivate the Audio Bridge using the Selcall function of his handheld portable radio Copyright MineCom 2005

Voice Enunciator This device is used to monitor alarm conditions and when an alarm is activated, the device automatically transmits a pre-recorded (stored) voice message over one or more radio channels. Voice Enunciator next Copyright MineCom 2005

…..Pump 5 - over temperature alarm
Voice Enunciator up to 80 seconds of solid state, battery-backed memory provide natural voice storage push button or remote activated voice announcements in any language stores pre-recorded voice messages individual voice messages can be activated remotely by a PC, PLC or even a handheld radio …..400 level Gas Detected …..Pump 5 - over temperature alarm …… 635 level Sub station, Breaker tripped out …..Blasting in 30 minutes, Blasting in 30 minutes Copyright MineCom 2005

Power Supply The Power supply is considered as a critical component of the system, providing a regulated 12 volts DC, to power all electronic devices in the rack enclosure. Power supplies offered will vary dependant on the country of use. The power supply MUST be capable of handling large fluctuations in input power, without failing. 240VAC – 12VDC Power Supply Battery Back Up next Copyright MineCom 2005

Power Supply Input voltages from 80VAC up to 240VAC
Output voltages from 12, 24 or 48VAC Output current from 10 to 30 amps Battery back up from 4 to 12 hours Some units are equipped with on-board metering and alarm functions Copyright MineCom 2005

VMLA in-line amplifier
The VMLA (VHF-Mini-Line-Amplifier) mini amplifier providing basic voice and data communications with limited on-board diagnostics PLUS – On-board ‘drive-by’ diagnostics displaying TX/RX device OK, TX/RX ALC operating. No special tools or coax connectors required MineCom’s simplified electrical style proprietary connection 350 or 500m separation 12, 24 or 48VDC operation Voice Data 350m 500m 12,24,48v Copyright MineCom 2005

VMLAD The VMLAD (VHF-Mini-Line-Amplifier Diagnostics) mini amplifier providing basic voice and data communications PLUS - Manual Line Length Compensation the gain of the amplifier is manually adjustable to compensate for the losses in the cable back to the next amplifier Digital on-board ‘drive-by’ diagnostics displaying signal strength, voltage level and current drain. No special tools or coax connectors required 350 or 500m separation 12, 24 or 48VDC operation D Voice Data m 12,24,48v Copyright MineCom 2005

SMARTTune The SMARTTune mini amplifier provides basic voice and data communications PLUS - Automatic Line Length Compensation the gain of the amplifier adjusts automatically to compensate for the losses in the cable back to the next amplifier Digital On-board ‘drive-by’ Diagnostics displaying signal strength, voltage level and current drain. No special tools or coax connectors are required MineCom’s simplified electrical style proprietary connection Up to 500m cable separation 12, 24 or 48VDC operation Voice Data Auto 500m 12,24,48v Copyright MineCom 2005

VLAV The VLAV (VHF-Line-Amplifier-Video) amplifier providing voice, data & video communications with limited on-board diagnostics PLUS – On-board ‘drive-by’ diagnostics displaying TX/RX device OK, TX/RX ALC operating. No special tools or coax connectors required MineCom’s simplified electrical style proprietary connection 350 or 500m separation 12, 24 or 48VDC operation Voice Data Video 12,24,48v Copyright MineCom 2005

VLAVD The VLAV (VHF-Line-Amplifier-Video-Diagnostics) amplifier providing voice, data & video communications with limited on-board diagnostics PLUS – PC based Diagnostics monitoring – RF levels, Volts, current and AC/DC fail for Power Couplers No special tools or coax connectors required MineCom’s simplified electrical style proprietary connection 350 or 500m separation 12, 24 or 48VDC operation D Voice Data Video 12,24,48v Copyright MineCom 2005

VLAVD-IS The VLAVD-IS (VHF-Line-Amplifier-Video-Diagnostics Intrinsic Safety) amplifier providing voice, data & video communications with limited on-board diagnostics PLUS – PC based Diagnostics monitoring – RF levels, Volts, current and AC/DC fail for Power Couplers No special tools or coax connectors required MineCom’s simplified electrical style proprietary connection 350 or 500m separation 12VDC operation Voice Data Video 12,24,48v Copyright MineCom 2005

VWACA The WACA (VHF-Wide-Area-Coverage-Amplifier) amplifier - voice, data & video designed to provide communications over a wide area, such as surface coverage, large underground workshops. It utilises an external antenna, which can be a unity gain or hi-gain omni directional antenna or a hi-gain Yagi style directional. 24VDC operation Voice Data Video Copyright MineCom 2005

VBU1 Branch Unit The VBU1 (VHF-Branch-Unit 1) single branch unit allows a cable to be ‘tee-d off’ or ‘split off’ into a side tunnel or level – No special tools or coax connectors required MineCom’s simplified electrical style proprietary connection Copyright MineCom 2005

VBU2 Branch Unit The VBU2 (VHF-Branch-Unit 2) Dual branch unit allows two cables to be ‘tee-d off’, or ‘split off’ from the main cable at a cross junction – No special tools or coax connectors required MineCom’s simplified electrical style proprietary connection Copyright MineCom 2005

VTB Termination Box VTB (VHF-Termination-Box) Termination Boxes are installed at the end of ALL cable runs, terminating the cable into a 75ohm load as well as protecting the end of the cable from the environment – No special tools or coax connectors required MineCom’s simplified electrical style proprietary connection Copyright MineCom 2005

VJB Joiner Box VJB (VHF-Joiner-Box) Joiner Boxes are used to repair cable breaks as well as protecting the ends of the cable from the environment – No special tools or coax connectors required MineCom’s simplified electrical style proprietary connection Copyright MineCom 2005

VTB-ANT Termination Box with Antenna
The VTB-ANT (VHF-Termination-Box-Antenna) is a modified Termination Box equipped with a Phel antenna, to provide additional ‘off-air’ coverage at the end of the cable run – No special tools or coax connectors required MineCom’s simplified electrical style proprietary connection Copyright MineCom 2005

VBU1-ANT Branch Unit with Antenna
The VBU1-ANT (VHF-Branch-Unit-Antenna) is a modified single branch unit equipped with a Phel antenna in the branch port, to provide additional ‘off-air’ coverage at a mid way point along the cable run – No special tools or coax connectors required MineCom’s simplified electrical style proprietary connection Copyright MineCom 2005

VVAU Variable Attenuator
VVAU (VHF-Variable-Attenuator Unit ) provides additional attenuation in a cable run between two amplifiers, allowing a shorter length of cable to be used – No special tools or coax connectors required MineCom’s simplified electrical style proprietary connection Copyright MineCom 2005

VVBU1 Video Branch Coupler Unit
The VVBU1 (VHF-Video Branch-Unit 1) Video branch coupler unit allows the output from a video camera modulator to be coupled directly into the leaky feeder cable – No special tools or coax connectors required MineCom’s simplified electrical style proprietary connection Copyright MineCom 2005

VPC Power Coupler Unit VPC (VHF-Power Coupler Unit ) the DC power supplied from the head end will only power ‘X’ number of devices dependant on – + the voltage used (12, 24, 48VDC) + the current drain of the amplifiers used One, or more VPC will be required to maintain the correct DC voltage level in the system, by ‘injecting’ additional DC power into the leaky feeder cable to down-line power the additional amplifiers – No special tools or coax connectors required – MineCom’s simplified electrical style proprietary connection next Copyright MineCom 2005

Understanding Leaky Feeder Systems

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