RT5201 Remote Control Unit - Operators Manual

TRANS WORLD COMMUNICATIONS, INC. • A ~~I~CJN COMPANY

RTS201 _REMOTE CONTROL

OPERATOR'S MANUAL

l~aN5\NOMLi:J rAfor communications

Manual No. RT5201-MSOPPublication #990427Printed: Auguat 1989

304 Enterprise StreetEscondido, CA 92029, U.S.A.

Phone: (619) 747-1079, Telex 695-433Fax (619) 741-1658

WARRANTY

Trans World Communications, Inc. (TWC) warrants that new TWC equipment has been manufacturedfree of defects in design, material and workmanship. If the equipment does not give satisfactory servicedue to defects covered by this warranty, TWC will, at its option, replace or repair the equipment free ofcharge.

The warranty is for a period of 90 days from the date of installation. In the event that the equipment isnot installed within 90 days of factory shipment, satisfactory evidence of the installation date must besubmitted.

LIMITATIONS:

This warranty does not cover physical damage caused by impact, liquids or gases. Defects caused bylightning, static discharge, voltage transients, or application of incorrect supply voltages are specificallyexcluded from this warranty.

RETURN OF EQUIPMENT· USA:

The equipment shan be returned freight prepaid to the Service Department, Trans World Communications,Inc., 304 Enterprise Street, Escondido, California 92029. The equipment should be packed securely, asTWC will not be responsible for damage incurred in transit Please include a letter containing the follow­ing information:

1. Model, serial number, and date of installation.2. Name of dealer or supplier of equipment3. Detailed explanation of problem.4. R€;turnshipping instructions.

TWC will return the equipment prepaid by United Parcel Service, Parcel Post or truck. If alternate ship­ping is specified, freight charges will be made collect.

RETURN OF EQUIPMENT· FOREIGN:

Write for specific instructions. Do not return equipment without authorization. It is usually not possibleto clear equipment through U.S. Customs without the correct documentation. If equipment is returnedwithout authorization, the sender is responsible for all taxes, customs duties and clearance charges.

LIMITED PARTS WARRANTY:

This warranty shall cover all parts in the equipment for a period of 12 months from the date of installa­tion, subject to the previous conditions and limitations. The parts will be replaced free of cost. The laborcharges will be made at the current TWC hourly service rate.

PARTS REPLACEMENT:

If it is not practical, or the purchaser does not want to return the equipment to the factory, this warranty islimited to the supply of replacement parts for a period of 12 months from the date of equipment installa­tion. The following instructions for the supply of replacement parts should be followed:

1. Return defective parts prepaid to: Parts Replacement, Trans World Communications, Inc., 304Enterprise Street, Escondido, California 92029.

2. Include a letter with the following information:a) Part number(s).b) Serial number and model of equipment.c) Date of installation.

Parts returned without this information will not be replaced. In the event of a dispute over the age of thereplacement part, components date coded over 24 months prior will be considered out of warranty.

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11

TABLE OF CONTENTS

SECTION 1 - GENERAL INFORMATION

1.1 Introduction 1-1

1.2 Control Signalling 1-1

1.3 Transceiver Response 1-1

1.4 Technical Specifications 1-1

SECTION 2 -INSTALLATION

2.1 Transceiver Connections 2-1

2.2 Power Supply 2-1

2.3 Balance ~heck, 2-Wire System Only 2-12.4 4- Wire To 2-Wire Conversion 2-1

2.5 Dc Keying Option Instructions 2-1

SECTION 3 - OPERATION

3.1

3.2

3.2.1

3.2.2

3.2.3

3.2.4

3.2.5

3.2.5

3.2.6

3.2.7

3.2.8

3.2.9

3.2.10

3.2.11

3.2.12

3.3

3.3.1

3.3.2

3.4

3.5

3.63.7

3.7.1

3.7.2

3.7.3

3.8

3.9

3.10

3.11

Introduction " 3-1

Front Panel Controls 3-1

Power On/Off, Audio Gain Control 3-1

RemotelLocal Control Selection 3-1

Speaker On/Off 3-1

Squelch On/Off 3-1Mode Switches 3-1

Mode Switches 3-1

Automatic Antenna Tuner Control 3-1

External Amp On/Off 3-1Scan Mode Initiate Button 3-1

Up/Down Tuning Buttons 3-1Se1cal1 Buttons 3-1

Keypad 3-1

Backlight Switch 3-1Front-Panel Indicators 3-1

Frequency Display 3-1

Loudspeaker 3-2Front-Panel Connector 3-2

Channel Frequencies 3-2

Operation - Memory-Channel Selection 3-2

Operation - Free-Tune Channel 3-2

Programming The Free-Tune Channel 3-2

Programming The Free-Tune Channel For Half-Duplex Frequencies 3-2

Recalling The Free-Tune Channel 3-2

Fine Tuning The Transceiver 3-2

Operation - Scan Mode 3-3

Operation - Selcall 3-3CW Sidetone 3-3

III

SECTION 4 - OPERATING NOTES

4.1 Answer-Back 4-1

4.2 MIC-GAIN"Adjustment 4-14.3 Side Tone - 4-1

4.4 "Watchdog" Timer ........................................................•........ 4-1

FIGURES

1-1 Remote-Control Unit 1-0

2-1 Component Location Diagram, Frequency Control Module, M9RC : 2-22-2 Component Location Diagram, Control Head 2-3

3-1 Remote Control- Front Panel Controls 3-3

TABLES

1-1 Technical Specifications 1-1

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FIGURE 1-1.Remote Control Unit.

1-0

SECTION 1GENERAL DESCRIPTION

1.1 INTRODUCTIONThe RT5201 remote control is an audio-dependent controlsystem which allows great physical separation from thetransceiving equipment to the operating point The unitmay be used over any full-duplex (continuously bidirec­tional) audio link; including a twisted pair (supplied), goodquality leased line, microwave link, etc.

1.2 CONTROL SIGNALLINGThe remote control achieves its control signalling using anAFSK data transmission standard-Bell 103, and runs at600 baud. A microprocessor at the control head interpretsthe various functions and commands, and translates theminto serial data bursts. The data bursts are then futher

translated into audio tones and sent over the twisted pair(or other link) to the transceiver.

1.3 TRANSCEIVER RESPONSEThe transceiver has the same data capability, and when itreceives the data burst, puts out an answerback to let thecontrol head know that it was received correctly. This"ARQ" type of system ensures that the control head showsonly valid information.

1.4 TECHNICAL SPECIFICATIONSTable 1 defmes technical specifications of the remote con­trol.

TABLE 1-1.Technical Specifications.

REMOTE INTERFACE: 2-wire line, 600 ohms nominal, bidirectional, or 4-wire unbalanced.

TRANSCEIVER INTERFACE: 2-wire line, 600 ohms, RS-232 in/out, or 4-wire unbalanced.

LINE LEVELS: -10 dBm to +3 dBm.

DATA TRANSMISSION MEDIUM: AFSK, U.S. standard tones.

DATA FORMAT: ASCII, 600 Baud, 8 bits, with asynchronous simplex acknow-ledgment system sent in four byte bursts.

CONTROLS: 16 key Keypad (Channel, Frequency, Selective Call Code/Select,Scan Frequency Step Up/Down), Audio Gain, Mode (USB, LSB,AM), Squelch (On/Off), Coupler Tune Initiate.

DISPLAY: Liquid crystal (channel number, frequency, selective-calling code,link status).

AUDIO: Internal loudspeaker, 2-W output.

DISTORTION: Less than 5 % added.

MICROPHONE INPUT: Low impedance dynamic, internal gain control and VOGAD.

TRANSIENT PROTECTION: Metal-oxide varistor, 2-wire systems.

POWER SUPPLY: 12 Vdc @ 1 Amp maximum.

ENVIRONMENT: Fully waterproof and submersible.

TEMPERATURE RANGE:

SIZE:

WEIGHT:

11.0 em W x 10.8 em H x 31.8 cm D (4.4 ft x 4.3 ft x 12.5 ft).

2.3 kg (5.01 Ibs)

Specifications subject to change without notice.

1-1

SECTION 2INSTALLATION

-,

2.1 TRANSCEIVER CONNECTIONSUse the accessory cable provided to connect the controlhead to the transceiver. Plug the large connector into J2connector on the transceiver, and insert the small connec­tor into the control head.

If more than 10 meters of connecting cable are required, asplice may be made or a good voice-grade, leased linemay be obtained for the purpose, if the 2-wire system isused. Conventional telephone lines may not be suitable foruse with the remote, since harmonic and other undesirabledistortions may be present in unknown quantity. The poorbalance of such phone lines also detracts heavily from sys­tem performance.

2.2 POWER SUPPLYThe head is designed to run from the +12 Vdc from thetransceiver. Dc is brought out in the four-conductor cableprovided.

2.3 BALANCE CHECK, 2·WIRE SYSTEM ONLYAfter the balanced line has been connected, it may benecessary to adjust the balance on the line at both ends ofthe link. This will only be required, however, if the line is"lossy" (has significant energy losses), or is very muchlonger than the one provided.

To check the balance, open the' cover of the control headand remove the bottom cover of the transceiver to gainaccess to the M9RC module.

On the M9RC module, use a scope or a Sinadder tomeasure the ac audio voltage across R55. R55 is locatednear the line transformer between two potentiometers, oneof which is R52. See Figure 2-3.

Remove U28 from the M9RC module and short pin 12 ofU21 to pin 16 of U21 (+5 V). This makes a tone go out

2-1

from the transceiver to the control head. Adjust R52 for anull in, the tone as monitored at R55. Replace U28 afterpowering down the transceiver. Repower the transceiver.

In the control head, power down and remove U12 (Figure2-4). Short pin 8 of U12 to pin 16 of U12 at its socket.Monitor the non-ground side of the volume control withthe scope or Sinadder. Adjust R29 on the PC board for anull in the transmitted tone. The transceiver should besquelched during this adjustment. R29 is a potentiometernear the line transformer. Replace the covers.

2.4 4·WIRE TO 2-WIRE CONVERSIONRemove the cover from the control head, remove the con­nectors attached to the control-head PC board and then liftit out. Remove the bottom cover of the transceiver. Gainaccess to the M9 PCB in the transceiver and remove it Itis best to place the M9 on an anti-static bag like the onesused to ship PCB's.

In the control head, remove the jumper in transformer T2holes "3" and "4." Solder the transformers provided in the2-wire kit (part Number 410028) into both the M9 and thecontrol head PCB (Tl on the M9RC - see Figure 2-1, andT2 on the control head - see Figure 2-2).

On the M9, remove the 22-gauge jumpers from "A" to"C", and from "B" to "D." Now jumper together "A" to"X", and "B" to "Y." Replace the M9 PCB.

In the control head, change R38 from 113152 to 113332, a3.3-kilohm, 1/8-W resistor. Reinstall the control-head PCboard in the remote control.

Perform the balancing procedure jn paragraph 2.3.

2.5 DC KEYING OPTION INSTRUCTIONSRemove the wire from J5 pin 8 and reinsert the pin in J12,pin 1. Use the two-pin female connector provided to matewith J12.

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SECTION 3OPERATION

3.1 INTRODUCTIONThe remote control is used in conjunction with thetransceiver. Its operation is similar to that of thetransceiver and most of its control functions are the same.Figure 3-1 shows the front panel of the remote controlwith functions defmed by numerical call-outs. These call­outs are referenced in the text by numbers in parenthesesfollowing the section subheadings.

3.2 FRONT-PANEL CONTROLSOperator controls on the transceiver front panel are as fol­lows:

3.2.1 Power On/Off, Audio Gain Control AUDIOGAIN) (1)

Turns the unit off in the OFF position. (The transceivershould be left on when using the remote control, and viceversa). Adjusts the audio volume in receive mode. FullCCW position is minimum volume and full CW position ismaximum volume.

3.2.2 Remote/Local Control SelectionThe display on the remote indicates "R.C. OFF" when thecontrol is at the transceiver. The display on the transceiverwill indicate "R.C. ON" when the control is from theremote. To restore control at either the. remote or thetransceiver, press the "F' button.

3.2.3 Speaker On/Off (SPEAKER) (2)A two-position toggle switch that can be used to turn theloudspeaker off.

3.2.4 Squelch On/Off (SQUELCH) (3)This turns the squelch circuits on. The squelch eliminatesbackground noise and is internally set to open on weakvoice signals.

3.2.5 Mode Switches (MODE) (4, 5, and 6)The three mode switches are labeled 4, 5, and 6; they areused to select either USB or LSB operation (4), turn theAM carrier injection on (5), and turn the CW circuitry on(6).

LSB (4). To select LSB operation, turn the USB/LSBswitch to LSB, the AM switch to Off and the CW switchto PIT.

NOTELSB is usually used if there is interference on the othersideband. In many countries (including the USA) thismode is illegal and will not be fitted into the transceiver.

USB (4). Used for most normal SSB operation. Turn theUSB/LSB switch to USB, the AM switch to Off, and theCW switch to PIT.

3-1

AM (5). Compatible AM (AME). This mode is used toprovide a signal that is intelligible to an AM station. It isunlikely to be required for normal communications. Turnthe USB/LSB switch to USB, the AM switch to AM andthe CW switch to PIT.

CW (6). This mode is for use with RITY systems. Turnthe USB/LSB switch to USB, the AM switch to Off, andthe CW switch to CWo

3.2.6 Automatic Antenna Tuner Control (ATU) (7)The ATV switch is used to initiate a tune cycle of anAutomatic Antenna Tuner (ATlOOor RATlOO).Wheneverthe switch is depressed, the tuner will go into a tune cycle;the tuning is automatic and a tone is present in theloudspeaker during the tune cycle.

3.2.7 External Amp On/Off (AMPL) (8)If an external RF power amplifier is used, its PIT functionmay be disabled by turning this switch to Off.

3.2.8 Scan Mode Initiate Button (SCAN) (9)Used to control the transceiver scan mode. See section 3.9for operation. The unit scans the same way as thetransceiver. The transceiver scans channels at the rate ofone channel every three seconds.

If the selective call system is fitted, the scan is stopped bythe selective call when a call is received.

3.2.9 Up/Down Tuning Buttons (i,J,) (10, 11)Switch 10 controls the Up tuning and 11 controls theDown tuning. See section 3.8 for operation.

3.2.10 Selcall Buttons (S.C., CALL)(12, 13)

Switch 12 controls the entering of the 3-digit Selcall codeand switch 13 controls sending of the Selcall code. Seesection 3.10 for operation.

3.2.11 Keypad (14)The keypad is used to program channel frequencies. Seesections 3.7 and 3.8 for operation.

3.2.12 Backlight Switch (LIGHT) (15)This is a two-position toggle switch that turns the displaybacklight on or off.

3.3 FRONT-PANEL INDICATORSIndicators on the transceiver front panel include the fol­lowing:

3.3.1 Frequency Display (16)The display shows the selected channel and/or channel fre­quency. A moving decimal point indicates whether a

receive or transmit frequency is displayed. For furtheroperation, see sections 3.6 and 3.7.

3.3.2 Loudspeaker (17)The speaker is used during receive and its audio output iscontrolled by the setting of the AUDIO GAIN control(3.2.1). Turning the SQUELCH switch (3.2.4) on willmute the speaker during conditions of background noise orextraneous single-tone signals.

3.4 FRONTmpANEL CONNECTORAudio Connector (AUDIO). A 5-pin audio connector isused for either handset or CW operation.

To operate on CW (morse) plug the key into either of theaudio sockets and use either .USB or LSB. The transmitterautomatically switches on when the key is pressed. Make ashort pause in the keying and the transceiver will return toreceive mode.

In microphone operation, the internal VOGAD circuitautomatically adjusts the audio gain to provide full trans­mitter output Speak close to the microphone in a clearvoice. Shouting will not provide any increased output andmay reduce intelligibility.

3.5 CHANNEL FREQUENCIESThe preset channel frequencies must be programmed at thetransceiver. To recall any channel frequency, press the "F'key as on the transceiver.

3.6 OPERATION mMEMORYmCHANNElSELECTION

After specific memory channels have been programmed,recalling them is a simple matter. The following procedureis used.

1. Press the "C" key.2. Press the two-digit channel number.

NOTEAll channel numbers have two digits-01 to 99. Channelselection is the only function available in Mode 3.

3. Press the "F' key to display the receive frequency (themoving decimal pointer on the display will be in the"receive" location).4. Press the "F' key again to display the transmit frequen­cy (the moving decimal pointer on the display will be inthe "transmit" location).

NOTEContinuously pressing the "F" key will cause the displayto alternate between monitoring the receive and transmitfrequency. The display will automatically return to the"receive" frequency after a transmit cycle is ended and thePTT is released.

3-2

3.7 OPERATION mFREEmTUNE CHANNELChannel 00 is used for free tuning the transceiver. Bothsimplex and half-duplex frequencies can be programmedinto channel 00. The last entered frequency is retained inthe transceiver memory.

3.1.1 PROGRAMMING THE FREEmTUNECHANNEL

1. Press the "C" key.2. Press the "0" key twice.3. Enter desired channel frequency.4. Press the "F' key.(The selected frequency should now be displayed with themoving decimal pointer at the "receive" location).

3.7.2 PROGRAMMING THE FREEmTUNE CHANmNEl FOR HALFmDUPLEX FREQUENCIES

When one frequency is entered, the transceiver automat­ically assumes that it is a simplex frequency. For half­duplex operating, do the following:

1. Do steps 1 through 4 of section 3.7.1. This programs thereceive frequency.2. Press the "F' key.3. Enter the desired transmit frequency.4. Press the "F' key. The decimal pointer should now bein the "transmit" location.

3.7.3 RECALLING THE FREEmTUNE CHANNELSince the last frequency programmed into the free tunechannel is stored in memory, it is an easy matter to recallthis channel.

1. Press the "C" key.2. Press the "0" key twice. The transceiver is now in thefree tune mode and the last entered frequency is displayed.

3.8 FINE TUNING THE TRANSCEIVERThe up and down buttons in the front panel permit tuningof the transceiver frequency up or down from the originalprogrammed frequency. The following procedures apply:

1. A single push steps the transceiver 100 Hz. The fre­quency can be changed in 100-Hz steps either up or downby pushing the appropriate button continuously (push, thenrelease-push, release-etc.).2. Only the receive frequency can be changed in theabove-mentioned manner. Any change entered is retainedonly until the channel is changed. If the channel ischanged and then changed again back to the original chan­nel, the original frequency is once again displayed; anyfrequency offset previously put in is forgotten.3. On the free-tune channel (CHOO), it is possible tochange the frequency in memory permanently by pressingthe "F' key after any up/down frequency stepping.

3.9 OPERATION· SCAN MODEThe transceiver can scan between 2 and 98 channels whenin the scan mode. Note that the desired channel frequen­cies must be programmed at the transceiver. The scan limit

must also be set at the transceiver. See the Operation Sec­tion of the transceiver technical manual for further details.

1. To initiate the scan mode for a desired frequency, pressthe "SCAN" key. The channels that will be scanned aredefined by the scan limit previously set and retained inmemory in the transceiver.

NOTE

Channel numbers being scanned will not be displayed bythe Remote Control during the scan sequence.2. To stop the scan sequence, press the "SCAN" keyagain.

NOTEIt is necessary to stop the scan mode to enter new keypadfunctions.

3.10 OPERATION· SELCALLThe selective-calling system is an optional feature. Checkthat it is fitted to the transceiver before using this function.

Each transceiver is assigned a selective-call code (000 to254). This code is internally programmed in the Selcallmodule.

Press the "S.C." key and enter the three-digit code for thedesired station. Press the "CALL" button, this will switchthe transmitter on and will then send the selective callcode.

The station called will stop scanning and send back atranspond signal. The Selcall module at the station calleddisplays "CALL" on the LCD display and sounds the callalarm tone at both stations. -

When a call is received, press the "SCAN" key to stop thescan. After the call is completed, press any key to cancelthe "CALL" display. If the scan mode is in use, press the"SCAN" key again to initiate scan.

3.11 CW SIDETONE

The remote control has been updated to include an audiomuting circuit which suppresses the signalling "chirps"and audio sidetone when in TX sidetone, remove D9.

3-3

3.12 OPERATION- TRANSCALLIRThe Transcall/R feature is optional. Check that it is in­stalled before attempting to use it.

Each transceiver in the Transcall/R domain utilizes thethree-digit Selcall code (001 to 255) for identification.This is internally programmed in the option module. Inaddition, each unit in the system should be programmed toscan the same number of "Transcall" channels. This isalso an adjustment in the option module (see Section 12.2of the technical manual).

To initiate a Transcall/R, press the "S.C." key and enterthe three-digit code for the desired station. Flip the toggleswitch from "SC" to "TC", and press the "CALL" buttonafter the scan has begun. An arming tone will sound, andthe transceiver will now be under full control of theTranscall/R circuit. Normal operation involves scanning,along with brief transmissions on each channel. Whenboth stations become synchronized, they will step togetherand seek the channel providing best communications. Fol­lowing this sequence (lasting a maximum of five minutes),the transceiver will automatically switch to the best chan­nel and sound an alarm. A "no contact" beeping tone willbe heard at the sending station if the stations do not be­come synchronized.

3.12.1 ABORT/EXIT FROM TRANSCALLIR MODEThe Transcall/R calling sequence may be stopped inprogress, provided that the two stations have not yetsynchronized. To abort, the calling station must hold the"CALL" key in for two seconds to stop the transmission.

Exiting the TraI).scall/Rmode (either before "CALL" ispressed, or after the best channel has been selected), isachieved by flipping the toggle switch from "TC" to "SC",then pressing "F' on the keypad. The display will clearwithin three seconds.

3.12.2 TRANSCALL SCANWhen scanning in the Transcall/R mode, the receiving sta·tion will also respond to a valid selcall. The scan limit isdetermined by the setting internally programmed in the op­tion module.

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3-3

SECTION 4OPERATING NOTES

4.1 ANSWER-BACKWhen any command is given from the control head; i.e.,any button is pushed or any switch is toggled, a data burstis sent down to the transceiver and the control head waitsfor an answer indicating that the data was received. If thetransceiver, for some reason, does not receive the data cor­rectly, it will not send the answer-back. The control headwill send the data again, and keep trying until it gets ananswer.

The data bursts going from the control head to thetransceiver are only weakly audible at the control head, butthe answer-back will be audible as a beep coming backfrom the transceiver. The receiver's audio is muted duringthe answer-back tone.

Controls on the control head will be inactive after the timethe data burst starts and before the answer-back isreceived, so it is good practice to listen for the answer­back before going on to the next command.

The control head is currently programmed to try for theanswer-back 20 times, and then it will give up and indicate"Error." This means that in those 20 tries, no answer-backswere correctly received.

All the functions of the remote have to use the data bursts,including the P1T (transmit) function. When the P1Tswitch of the microphone is pressed, you must wait for the

4-1

answer-back burst before beginning communications. Ahigh level of background noise at or near the operatingposition can cause the outgoing data bursts to be garbled atthe transceiver. It may be necessary to reduce the MICGAIN in order to stop any such problem.

4.2 Mle-GAIN ADJUSTMENTThe MIe-GAIN adjustment is inside the control head, nearthe center of the PCB. Its designator is R6. It is recom­mended that the transmission of the unit under test bemonitored while the MIC GAIN is adjusted until thepresence of background noise is at a minimum and doesnot interfere with signalling. Going too far will cause finaloutput power to be reduced, as the audio drive may be­come insufficient.

4.3 SIDE TONEThere is some side tone in the control head while transmit­ting, and turning the loudness control up too far will causefeedback to occur. Turn the loudness down or turn theloudspeaker off while transmitting.

4.4 "WATCHDOG" TIMERThe remote control is equipped with a "watchdog" timerwhich, if the unit is left in transmit from the remote forlonger than five minutes, will cause the transceiver toautomatically revert to receive mode. For transmissionslonger than five minutes, unkey briefly every four minutesor so.