ERG Transit Systems MCROEM CONTACTLESS SMART CARD READER User Manual APPENDIX I

ERG Transit Systems CONTACTLESS SMART CARD READER APPENDIX I

USERS MANUAL

 Page 1 of 21   EMC Technologies Pty Ltd ABN 82 057 105 549 Unit 3/87 Station Road Seven Hills NSW 2147 Australia  Telephone      +61 2 9624 2777 Facsimile       +61 2 9838 4050 Email         syd@emctech.com.au www.emctech.com.au  Melbourne 57 Assembly Drive Tullamarine Vic 3043 Tel:   +61 3 9335 3333 Fax:  +61 3 9338 9260 Sydney Unit 3/87 Station Road Seven Hills NSW 2147 Tel:   +61 2 9624 2777 Fax:  +61 2 9838 4050 Brisbane 1/15 Success Street Acacia Ridge Qld 4110 Tel:   +61 7 3875 2455 Fax:  +61 7 3875 2466 Auckland (NZ) 47 MacKelvie Street Grey Lynn Auckland Tel:   +64 9 360 0862 Fax:  +64 9 360 0861          APPENDIX I OF TEST REPORT T50915R_F   Installation Manual     FCC ID:  Q47-MCROEM Manufacturer:  ERG Transit Systems Test Sample:  Contact less Smart Card Readers Model:   MCR_OEM Serial No:  14.7456MHz Unit: Antenna - 0350435, Main Board - 04273566  and 22.1184MHz Unit: Antenna - 05129574, Main Board - 0504009   Date:  27th October 2005
    Device Product Group MCROEM User Manual  Document No:  DPG-00604  Category:  431  Revision:  1.0  ERG Approvals  Author  Process Manager  Manager Name:  Dan Zorde  Stefan Walter  Gino Bertino Signature:    Date:           This material is confidential to ERG and may not be disclosed in whole or in part to any third party nor used in any manner whatsoever other than for the purposes expressly consented to by ERG in writing. This material is also copyright and may not be reproduced, stored in a retrieval system or transmitted in any form or by any means in whole or in part without the express written consent of ERG.
Device Product Group  Security Level 3  MCROEM User Manual DPG-00604  ERG Confidential © ERG 2005  Page 2 of 20 Revision 1.0 / 11 October 2005  Document History  Revision  Revision Date  Description  Author 0.1  8 Aug 2005  Draft   Dan Zorde 0.2  2 Sep 2005  Updates to Section 4.4 and onwards  Dan Zorde 0.3  21 Sep 2005  Updates as per advice from EMC Tech  Dan Zorde 0.4  11 Oct 2005  Change FCC ID to Q47-MCROEM  Dan Zorde 1.0  11 Oct 2005  First release  Dan Zorde
Device Product Group  Security Level 3  MCROEM User Manual DPG-00604  ERG Confidential © ERG 2005  Page 3 of 20 Revision 1.0 / 11 October 2005  Table of Contents 1 INTRODUCTION ....................................................................................................................................... 6 1.1 PURPOSE............................................................................................................................................. 6 1.2 SCOPE................................................................................................................................................. 6 1.3 TERMINOLOGY ..................................................................................................................................... 6 2 OVERVIEW OF THE MCR ........................................................................................................................ 7 3 MODULE ARCHITECTURE......................................................................................................................9 3.1 ELECTRICAL SPECIFICATION.................................................................................................................. 9 3.2 HOST SERIAL COMMUNICATION INTERFACE ............................................................................................ 9 3.3 POWER SUPPLY ................................................................................................................................. 10 3.4 RF CONTROLLER................................................................................................................................10 3.4.1 Transmitter............................................................................................................................... 10 3.4.2 Receiver ...................................................................................................................................10 3.4.3 Card Interface ..........................................................................................................................10 4 INTERFACE CONNECTIONS.................................................................................................................11 4.1 SUPPORTED COMMUNICATIONS INTERFACES ....................................................................................... 11 4.1.1 Communications Interface Connector ..................................................................................... 11 4.1.2 Communications Interface Connection.................................................................................... 11 4.2 SUPPORTED LCD INTERFACE ............................................................................................................. 11 4.2.1 LCD Interface Connector .........................................................................................................11 4.2.2 LCD Interface Connection........................................................................................................12 4.3 SUPPORTED I/O INTERFACES.............................................................................................................. 12 4.3.1 I/O Interface Connector............................................................................................................12 4.3.2 I/O Interface Connection ..........................................................................................................13 4.4 INTERCONNECTING CABLE................................................................................................................... 14 5 MECHANICAL SPECIFICATION............................................................................................................15 5.1 PHYSICAL DIMENSIONS....................................................................................................................... 15 5.1.1 Size ..........................................................................................................................................15 5.1.2 Mounting Holes ........................................................................................................................16 5.2 INDIVIDUAL COMPONENT DIMENSIONS................................................................................................. 17 5.2.1 Control Board Dimensions .......................................................................................................17 5.2.2 Antenna Dimensions................................................................................................................18 6 MOUNTING GUIDELINES ......................................................................................................................19 7 ANTENNA TUNING.................................................................................................................................20    List of Tables TABLE 1: TERMINOLOGY....................................................................................................................................... 6 TABLE 2: SERIAL INTERFACE CONNECTIONS........................................................................................................ 11 TABLE 3: LCD INTERFACE CONNECTIONS ........................................................................................................... 12 TABLE 4: I/O INTERFACE CONNECTIONS.............................................................................................................. 13 TABLE 5: PHYSICAL DIMENSIONS ........................................................................................................................ 15
Device Product Group  Security Level 3  MCROEM User Manual DPG-00604  ERG Confidential © ERG 2005  Page 4 of 20 Revision 1.0 / 11 October 2005   List of Figures FIGURE 1: MCROEM MODULE ............................................................................................................................ 7 FIGURE 2: MCROEM MODULE – OPERATION....................................................................................................... 8 FIGURE 3: MODULE ARCHITECTURE ...................................................................................................................... 9 FIGURE 4: INTERCONNECTING HOST CABLE ........................................................................................................ 14 FIGURE 5: TYPICAL STACKING ARRANGEMENT ..................................................................................................... 15 FIGURE 6: TYPICAL PHYSICAL ENVELOPE............................................................................................................. 16 FIGURE 7: CONTROL BOARD DIMENSIONS........................................................................................................... 17 FIGURE 8: ANTENNA DIMENSIONS....................................................................................................................... 18 FIGURE 9: CLEARANCE BETWEEN ANTENNA AND METALLIC OBJECTS..................................................................... 19 FIGURE 10: LOCATION OF TUNING CAPACITOR CV1 ............................................................................................. 20
Device Product Group  Security Level 3  MCROEM User Manual DPG-00604  ERG Confidential © ERG 2005  Page 5 of 20 Revision 1.0 / 11 October 2005   FCC Compliance Statement This device complies with Part 15 of the FCC rules.  Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation. This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules.  These limits are designed to provide reasonable protection against harmful interference in a residential installation.  This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications.  However, there is no guarantee that interference will not occur in a particular installation.  If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encourage to try to correct the interference by one or more of the following measures: • Reorient or relocate the receiving antenna. • Increase the separation between the equipment and receiver. • Connect the equipment into an outlet on a circuit different from that to which the receiver is connected. • Consult the dealer or an experienced radio/TV technician for help. The MCR was submitted and a grant of authorisation received from the FCC as a modular device under the intentional radiator requirements of part 15, Subpart C. The party that incorporates the MCR into their product is responsible for verification of the emissions produced by the final product and must adhere to the limits specified in the code of Federal Regulations 47, Part 15, Subpart B. Furthermore, a label must be applied on the exterior of the final product, referring to this enclosed module, which shall state, “Contains FCC ID: Q47-MCROEM” or “Contains Transmitter Module FCC ID: Q47-MCROEM”. Notice: When an AC to DC power source is used to supply power to the integrated equipment, the final equipment will also have to comply with the AC line conducted emissions according to FCC Part 15, Subpart B.    Warning:  Any changes or modifications not expressively approved by ERG Transit Systems could void the user's authority to operate this equipment
Device Product Group  Security Level 3  MCROEM User Manual DPG-00604  ERG Confidential © ERG 2005  Page 6 of 20 Revision 1.0 / 11 October 2005  1 Introduction 1.1 Purpose The purpose of this document is to provide summary technical details of the electrical interface and physical characteristic of the Multiprotocol Card Reader (MCR).  It is intended for use by third party developers wanting to integrate the MCROEM Module into new or existing products. 1.2 Scope This manual is intended for use by third party developers and integrators familiar with similar type of equipment. This manual contains technical information sufficient to give technical personnel an operational understanding of the MCR. 1.3 Terminology The following table contains a list of Equipment Terminology and their meanings. Table 1: Terminology Term  Definition A Amp(s), Ampere(s) ASK  Amplitude Shift Keying  bps  Bits per second BPSK  Binary Phased Shift Keying  CMOS  Complementary Metal-Oxide Semiconductor CPU  Central Processing Unit (microprocessor) CSC  Contact-less Smart Card Host  A processing unit communicating directly with and housing the MCR.  EIA  Electronic Industry Association EMC Electromagnetic Compatibility GND  Ground – negative supply Hz  Hertz, cycles per second IEC  International Electrotechnical Commission ISO  International Standards Organisation LCD  Liquid Crystal Display MCR  Multiprotocol Card Reader mm millimetre(s) NRZ-L  Non-return to zero - level  OOK On-Off keying PCB  Printed Circuit Board s second(s) TIA  Telecommunications Industry Association TTL  Transistor Transistor Logic
Device Product Group  Security Level 3  MCROEM User Manual DPG-00604  ERG Confidential © ERG 2005  Page 7 of 20 Revision 1.0 / 11 October 2005  2  Overview of the MCR  The MCROEM Module is an easy-to-use, economical means of introducing contact-less smart card capability into a host.   Figure 1 contains a picture of the MCROEM Module.  Section 3 provides an overview of the module architecture. Section 4 provides a description of the interface connector and pins.  Section 5 provides dimensional details, section 6 describes how the MCR is to be mounted inside the host and Section 7 describes the final tuning procedure.  Figure 1: MCROEM Module The MCROEM module is a compact contact-less reader, which enables developers to rapidly add contact-less functionality to new or existing products. Each MCR consists of a Control Board and Antenna Board; this set is tuned and tested at the factory prior to shipment.  Each set is shipped with a 100 mm interconnecting cable as shown in Figure 1. The MCR serves as the data communications link between customer smart cards and the host in which the MCR is installed.  For MCR-to-Card communications, the Control Board receives data signals from the host.  It then transmits the data signals via RF to a smart card held within reading distance of the MCR’s Antenna Board.  For Card-to-MCR communications, RF data signals from the smart card are received by the Control Board via the Antenna Board where they are sent to the host via connector 1 located on the Control Board.  Figure 2 contains a block diagram that illustrates the MCR mode of operation.
Device Product Group  Security Level 3  MCROEM User Manual DPG-00604  ERG Confidential © ERG 2005  Page 8 of 20 Revision 1.0 / 11 October 2005  AntennaControl BoardControla BoardConnectorAntennaConnectorInterconnect CableContactlessSmart CardLCDI/OHOSTInterconnect CableInterconnect CableInterconnect CableHOST LCDHOST I/OHOST 12VPOWER &COMMS Figure 2: MCROEM Module – Operation For implementation into simple products, the MCR can be utilised as the controller of the product, allowing for driving an onboard LCD and TTL I/O devices. Hence, all interfacing to the device is via the MCR host connector. With the implementation of LCD and I/O, the MCR CPU will, via commands from the host, display text/graphics and operate any I/O implemented via the CPU port pins. In more complex devices with their own LCD and I/O, or devices with no need for these features, these circuit options can be depopulated during manufacturing to reduce costs.
Device Product Group  Security Level 3  MCROEM User Manual DPG-00604  ERG Confidential © ERG 2005  Page 9 of 20 Revision 1.0 / 11 October 2005  3 Module architecture The Control Board contains a microprocessor, non-volatile memory, and radio frequency transmitting and receiving circuitry.  This board communicates with smart cards via a RF link provided by the Antenna Board, and to the host terminal or integrated product via a RS-422 or RS-232 serial protocol. The Antenna Board consists of a printed circuit board with copper traces forming the transmit and receive antenna.  The board is attached to a ferrite plate and a metal back plate that serves as a ground plane. Control of a device LCD and device I/O is achieved via direct access to port pins and the data bus on the CPU. By sending appropriate command instructions via the serial link, the LCD and device I/O can be operated. The module architecture is illustrated in Figure 3.  textCommsBuffer CPU RFControllerRFTx and RxCircuitHostConnectorSERIALHOST PORT12VdcFromHostControl Board 70-0700LCDConnector I/OConnectorAntenna Board70-0694 Figure 3: Module Architecture 3.1 Electrical specification 3.2  Host serial communication interface  Item  Description MCR to Host communication interface  Serial RS-232 and RS-422 full duplex.  MCR to host baud rate   Serial 9600bps to 460Kbps.
Device Product Group  Security Level 3  MCROEM User Manual DPG-00604  ERG Confidential © ERG 2005  Page 10 of 20 Revision 1.0 / 11 October 2005  3.3 Power Supply The MCROEM module derives power directly from the host. After supply power is applied to the MCR it will be operational in less than 1.2 seconds. Item  Description Supply voltage  12Vdc +10%/-5%, with ripple of less than 50mV peak-peak.  Supply current  Maximum 300 mA, typical 150 mA Input power requirements  Maximum 3.60 Watts 3.4 RF controller The standards supported by the RF controller are ISO/IEC 14443 Type A, ISO/IEC 14443 Type B and Mifare Standard. 3.4.1 Transmitter The MCR transmitter complies with the following specifications:  Item  Description Carrier Frequency  13.56 MHz + 7 kHz (ISO/IEC 14443-2:2001, 6.1) Modulation Rise and Fall Time  < 2.0 µsec (ISO/IEC 14443-2:2001, 8.1.2 and 9.1.2) ASK Modulation  100% Modified Miller (ISO/IEC 14443-2:2001, 7 and 8) 8%-14% NRZ (ISO/IEC 14443-2:2001, 7 and 9) 3.4.2 Receiver The MCR receiver complies with the following specifications: Item  Description Carrier Frequency   13.56 MHz  Subcarrier Frequency  847.5 kHz (ISO/IEC 14443-2:2001, 7, 8 and 9) Subcarrier Data  OOK Manchester (ISO/IEC 14443-3:2001 7 and 8) BPSK NRZ-L (ISO/IEC 14443-2:2001, 7 and 9)  3.4.3  Card Interface  The MCR module supports contact-less smart cards conforming to the following signal interface protocols: • ISO/IEC 14443 Type A. • ISO/IEC 14443 Type B.
Device Product Group  Security Level 3  MCROEM User Manual DPG-00604  ERG Confidential © ERG 2005  Page 11 of 20 Revision 1.0 / 11 October 2005  4 Interface Connections 4.1  Supported Communications Interfaces The serial interface between the Host and MCR supports both: • RS-422, full duplex • RS-232 The MCR is connected to the host via a 10-pin connector located on the Control Board.  The interconnection between the host and the MCR may be achieved using an interconnecting cable as shown in Figure 4. The default terminal to CAD communication speed is 460kbps for RS-422 and 115.2kbps for RS-232. Slower communication speeds are available via software selection on start-up.  4.1.1  Communications Interface Connector The MCR interface connector mates with a straight connector.  Straight connector:  Molex #22-01-2105 or equivalent 4.1.2  Communications Interface Connection Pin  Designation  Signal Level  Function 1  Reset  CMOS logic  Can be used to reset the MCR. 2  GND  Ground  Power Supply negative 3  +12V  +12Vdc  Power Supply positive 4  Rx-  RS-422 -ve  Serial data from Host to MCR 5  Rx+  RS-422 +ve  Serial data from Host to MCR 6  Tx-  RS-422 -ve  Serial data from MCR to Host 7  Tx+  RS-422 +ve  Serial data from MCR to Host 8  TxD  RS-232  Serial data from MCR to Host 9  GND  Ground  Power supply negative 10  RxD  RS-232  Serial data from Host to MCR Table 2: Serial Interface Connections If the Host provides a hardware reset, it will be a logic-level, active-low signal with a minimum pulse width of 10 microseconds. 4.2  Supported LCD Interface The interface between the device LCD and the MCR is buffered 5V TTL signalling. The MCR connection to an LCD is achieved via a simple 30 way flexible PCB connection to the CPU data bus and control lines. 4.2.1  LCD Interface Connector The MCR interface connector mates with a flexible PCB.  MCR Connector:  JST_FLZ_SM30
Device Product Group  Security Level 3  MCROEM User Manual DPG-00604  ERG Confidential © ERG 2005  Page 12 of 20 Revision 1.0 / 11 October 2005  4.2.2  LCD Interface Connection Pin  Designation  Signal Level  Function 1     Not used 2     Not used 3     Not used 4     Not used 5     Not used 6  Backlight   Ground  Switch for backlight ground 7  +5V  +5V  Power supply positive for backlight 8     Not used 9  B_/Reset  5V TTL  LCD Reset 10  B_CSLCD2  5V TTL  LCD chip select upper half 11  B_CSLCD1  5V TTL  LCD chip select lower half 12  B_D7  5V TTL  LCD data bus 13  B_D6  5V TTL  LCD data bus 14  B_D5  5V TTL  LCD data bus 15  B_D4  5V TTL  LCD data bus 16  B_D3  5V TTL  LCD data bus 17  B_D2  5V TTL  LCD data bus 18  B_D1  5V TTL  LCD data bus 19  B_D0  5V TTL  LCD data bus 20  B_LCD_CLK  5V TTL  LCD data clock 21  /B_LCDRW  5V TTL  LCD read write signal 22  B_A0  5V TTL  LCD address bus 23  CTRST  -20V  Negative supply for LCD contrast 24  LCD_Volt  +5V   Power supply positive for LCD 25  GND  Ground  Power supply negative for LCD 26     Not used 27     Not used 28     Not used 29     Not used 30     Not used Table 3: LCD Interface Connections 4.3  Supported I/O Interfaces The I/O interface between the device and MCR is 3.3V TTL signalling. I/O interfacing is via a 15-pin connector located on the Control Board. 4.3.1  I/O Interface Connector The MCR interface connector mates with a straight connector.  Straight connector:  Molex #51021-1500 or equivalent
Device Product Group  Security Level 3  MCROEM User Manual DPG-00604  ERG Confidential © ERG 2005  Page 13 of 20 Revision 1.0 / 11 October 2005  4.3.2  I/O Interface Connection Pin  Designation  Signal Level  Function 1  +12V  +12Vdc  Power Supply positive 2  +3.3V  +3.3Vdc  Power Supply positive 3 Temp1  Analogue  0-3.3V input 4  GND  Ground  Power Supply negative 5  Audio  3.3V TTL  PWM output 6  Audio_Vol  3.3V TTL  Volume control 7  Keyrow1  3.3V TTL  TTL input 8  Keyrow2  3.3V TTL  TTL input 9  Keyrow3  3.3V TTL  TTL input 10  Green_Led  3.3V TTL  TTL output 11  Yellow_Led  3.3V TTL  TTL output 12  Red_Led  3.3V TTL  TTL output 13  Key_Led1  3.3V TTL  TTL output 14  Key_Led2  3.3V TTL  TTL output 15  Key_Led3  3.3V TTL  TTL output Table 4: I/O Interface Connections
Device Product Group  Security Level 3  MCROEM User Manual DPG-00604  ERG Confidential © ERG 2005  Page 14 of 20 Revision 1.0 / 11 October 2005  4.4 Interconnecting cable Figure 4, show a suggested interconnecting cable when the MCR is connected to a remote host. When the MCR is fitted as part of a product, connectors on the MCR can be plugged straight onto matching sockets, eliminating the need for cables.  Figure 4: Interconnecting Host Cable Ferrite bead, Steward #28B1122-100, must be fitted as shown in Figure 4, on the power/communications cable connecting to the MCR
Device Product Group  Security Level 3  MCROEM User Manual DPG-00604  ERG Confidential © ERG 2005  Page 15 of 20 Revision 1.0 / 11 October 2005  5 Mechanical specification 5.1 Physical Dimensions The two components that form the MCR (Control and Antenna boards) are organised so that they can be physically separated by a distance of up to 100 mm, and connected via a connecting cable.  It is possible to stack the two components into a thickness of 24.5 mm.    Figure 5: Typical stacking arrangement 5.1.1 Size The guaranteed Reader volumetric envelope is shown in Figure 6.  It is acceptable to mount the MCR in a larger volumetric envelope if space is available. The Control Board and Antenna have the following dimensions:  Length (mm)  Width (mm)  Height (mm)  Tolerance (mm) Control Board  104  67  15.5  ± 0.5 Antenna Board  104  67 5.5  ± 0.5 Table 5: Physical Dimensions
Device Product Group  Security Level 3  MCROEM User Manual DPG-00604  ERG Confidential © ERG 2005  Page 16 of 20 Revision 1.0 / 11 October 2005     Figure 6: Typical physical envelope  5.1.2 Mounting Holes All mounting holes are M3.2.  The mounting holes are aligned and may be used with screws and plastic spacers to secure the MCR inside the product.  The 100 mm cable allows the Control Board and Antenna Board to be separated to accommodate different mounting scenarios. For instance, the boards could be stacked, mounted side by side or mounted on an angle.  Spacers between the shield and control pcb, ensure the shield remains fixed to the control pcb, and eliminates shield deformation during assembly into the final device.
Device Product Group  Security Level 3  MCROEM User Manual DPG-00604  ERG Confidential © ERG 2005  Page 17 of 20 Revision 1.0 / 11 October 2005    5.2  Individual Component Dimensions 5.2.1  Control Board Dimensions The Control Board dimensions, and the placement of the connectors, conform to those shown in Figure 7.   Figure 7: Control Board Dimensions
Device Product Group  Security Level 3  MCROEM User Manual DPG-00604  ERG Confidential © ERG 2005  Page 18 of 20 Revision 1.0 / 11 October 2005  5.2.2 Antenna Dimensions The Antenna conforms to the dimensions shown in Figure 8. The Antenna thickness is 5.5 mm.  Figure 8: Antenna Dimensions
Device Product Group  Security Level 3  MCROEM User Manual DPG-00604  ERG Confidential © ERG 2005  Page 19 of 20 Revision 1.0 / 11 October 2005  6 Mounting guidelines These guidelines are intended to assist product designers maximise the operation of the MCR in products: • Ensure that any metalwork and/or EMC coatings are at least 15 mm away from the sides of the antenna board in a horizontal plane and more than 5 mm below the vertical plane.  Designers should use the maximum possible clearance. • The top of the antenna PCB (non-metallic side) must face towards the card reading surface of the terminal and be less than 5 mm from the top surface.  Any increase in this distance will impact the Reader performance, and may result in the product being unable to meet the project’s specifications, particularly the operating distance. • The surface of the target area, which is directly above the Antenna Board, must be a non-metallic surface such as plastic and be free of any metallic particles.  • It should be possible to tune the reader using the tuning capacitor shown in Figure 10 while leaving the antenna PCB fixed to the product.  The product should ideally be designed to permit re-tuning once the MCR is fitted. • Removal of the shield to mount the MCR in ways not otherwise possible will breach the FCC regulations and void all warranty. • Ensure that the cable interconnecting the Antenna Board to the Control Board is located away from metal surfaces and that the cable is fixed to avoid movement.  Any movement may degrade the reader performance, as the cable is an active part of the antenna system. • Ideally, both the control and antenna PCBs should be kept together as a unit.  Figure 9: Clearance between antenna and metallic objects.
Device Product Group  Security Level 3  MCROEM User Manual DPG-00604  ERG Confidential © ERG 2005  Page 20 of 20 Revision 1.0 / 11 October 2005  7  Antenna Tuning  The MCR is tuned at the factory for maximum operating range.  It may be necessary to retune the MCR when it is mounted into a host device to compensate for the effects of the mounting environment (such as metallic parts or metallic paint near the antenna) and to ensure optimum performance.  For this function, use an active smart card that is initialised for use with the particular host application. 1)  With the MCR mounted in its operational environment place the test smart card onto the card reading surface of the terminal. Use a non-metallic spacer with the depth of the desired operating range.  For example, if the desired operating range is 50 mm, then place a 50 mm spacer.  Ensure that the host and MCR are powered. 2)  Verify operational range by running the host internal diagnostic routines. Via the tuning hole in the shield, adjust the tuning by rotating CV1 using a plastic tuning tool to maximise the operating distance.     Figure 10: Location of tuning capacitor CV1

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