Obsolete Product - No Longer Supported

The Model 410 Personal Patch (obsolete) is designed to provide reliable telephone interconnect operation at an exceptionally affordable cost. Complicated microprocessor programming steps (as with other interconnect models) have been replaced with simple jumper configuration. Level adjustments and radio connections are kept to an absolute minimum, in order to allow the installation process to be accomplished in the easiest possible manner. Further, user operation is simple and straightforward.

The Personal Patch provides DTMF equipped two-way mobile and handheld radios with the ability to make and receive telephone calls. The patch is fully compatible with both half-duplex (repeater installation) and simplex (base station installation) radio systems. It offers either of two popular methods of operation when used in simplex applications: VOX control or sampling control. The unit provides simple "*" up and "#" down operation, and either pulse or DMTF dialing. Inputs are provided for external CTCSS decode and COR. A mobile activity timer provides an automatic disconnect feature for those occasions when the mobile abandons the connection without properly disconnecting the call.

CES has a full line of DTMF encoding microphones compatible with many popular radio models, from low-cost basic to memory dialing types. Contact your sales representative for more information.

INSTALLATION

Telephone Line Connection A standard RJ-11 modular phone jack is provided on the rear panel of the unit for connection to the telephone line. Base Station or Repeater Connections Make the following connections to the base station or repeater station equipment. Connections are made to terminal block J2 located on the rear of the Personal Patch. A minimum of five (5) connections are required (Transmit Audio, Receive Audio, PTT, Power, and Ground). Two additional connections (CTCSS and COR) are optional. For assistance in determining the connection points in the radio equipment, see the illustration Figure "B" in the Appendix of this manual. It is also helpful to refer to the radio or repeater schematic diagram and service manual for additional information on where to make the physical connection.

JP7 Mobile Detect Mode

INSTALLATION

Adjustments:

Internal COR Mobile Detector (RV4) (not required if External COR is used)

(1) Apply power to the Personal Patch and base station or repeater.

(2) Beginning with RV4 fully clockwise, rotate it slowly until the "Noise" LED DS2 illuminates.

(3) Connect a service monitor to the receiver and generate an on-channel carrier. Vary the generator output and verify that the Noise LED goes out with a received carrier of approximately 12 dB SINAD, or the same point where the receiver becomes unsquelched. Repeat the readjustment of RV4 as necessary so that it illuminates when no carrier is present, and goes out when a useable carrier signal is received.

Transmit Audio (RV2)

(1) Set the service monitor to receive on the transmitter frequency.

(2) With the telephone line plugged into the rear panel connector, press the front panel switch to manually connect. A dial tone will be transmitted.

(3) Set RV2 for 4.0 KHz deviation as observed on the service monitor. The modulation should not be clipped or distorted. If the level can not be reached, or if the range is inadequate, remove jumper JP1.

(4) Press the front panel switch to disconnect the telephone line.

Receive Audio (RV3) (Jumper JP8 must be removed for this adjustment)

(1) Call the patch telephone line from another telephone.

(2) Manually answer the line by pressing the front panel switch.

(3) Have a mobile unit make a test transmission and adjust RV3 for a normal telephone line level as heard on the telephone. If an AC voltmeter is available, monitor the telephone line and set RV3 for approximately 500 mV (-4 dBm) on voice peaks from the mobile.

(4) Verify that the mobile can disconnect the call with a "#" from the DTMF microphone or encoder, and connect with a "*". If not, then adjust RV3 slightly CW or CCW until the mobile is able to reliably connect and disconnect.

(5) Reinstall jumper JP8, if desired (disables Reverse Patch Enable).

VOX Sensitivity (RV1) (Not required for half-duplex installation)

(1) Jumpers JP5, JP8, and JP9 must be removed.

(2) Jumper JP6 must be installed.

(3) Rotate RV5 fully clockwise.

(4) Call the patch from another telephone.

(5) Press the front panel switch to manually connect the call. Wait 20 seconds.

(6) Adjust RV1 so that the PTT LED illuminates when you speak into the telephone, and goes out after not speaking. Further adjust RV1 so that this proceedure responds reliably and for lower level voice audio.

(7) Reinstall jumper JP9 if desired (enables Mobile Activity Timer).

Sampling Rate (RV5) (Not required for half-duplex installation)

(1) Jumpers JP5, JP6, and JP9 must be removed.

(2) Remove the telephone line from the rear panel of the Personal Patch.

(3) Connect the patch manually by pressing the front panel switch, or connect from mobile.

(4) Observe the periodic sampling indications (PTT LED momentarily goes off) and adjust RV5 for the shortest period of time that it is on, while periodically having the mobile transmit for a short period to confirm that both the PTT and Noise LED's will stay off during the period the mobile is transmitting.

(5) Reinstall jumper JP9 if desired (enables Mobile Activity Timer).

Verify that all jumpers are configured in accordance with the manner selected for the Personal Patch to operate in this installation.

The installation procedure has been completed.

Refer to the OPERATION section that follows in this manual for instructions on how to use the 410 Personal Patch.

Should the Personal Patch not operate correctly, please refer to the "In Case of Difficulty" section of this manual.

OPERATION

In a half-duplex radio system, that incorporates the use of different transmit and receive frequencies, and allows the base station or repeater to simultaneously transmit and receive at the same time. When the Personal Patch is used in this manner, the mobile can transmit at any time to reply to the telephone line caller, or to disconnect the patch. This mode of operation affords the best approach to telephone interconnection for conventional simplex/half-duplex mobiles.

In simplex systems where a single-frequency is used, the base station radio must be unkeyed before it can detect the presence of a transmitting mobile. Therefore, there are some restrictions on when the mobile can dial or speak. Two different modes of control are available for the Personal Patch when configured for simplex systems. In the Sampling mode, it will cause a periodic interruption, or receive "window", while transmitting. These "samples" cause the patch to unkey the transmitter in order to determine if the mobile is transmitting. If it sees mobile carrier, it then will remain in a receive mode - routing the mobile audio to the telephone line for the duration that the mobile transmits. When the mobile unkeys, the patch reverts back to the transmit mode and continues with sampling the receiver for subsequent mobile activity. In this mode, each time the mobile wants to talk or dial, it first has to transmit long enough for the next sample to occur. This takes approximately 1/2 second when ther is no audio from the telephone line, or approximately 8-seconds when audio is present. The advantage of the Sampling mode is that the mobile will always have the ability to interrupt the conversation or to disconnect.

In VOX mode, the base station will transmit whenever the landline party speaks. After a pause in telephone line audio, the base station will revert back to the receive mode - allowing the mobile to transmit. When using the VOX mode, the operation is susceptible to telephone line noise or perhaps music from the telephone line keeping the connection in a continual transmit mode and not permitting the mobile to transmit. Similarly, the mobile unit may not be able to disconnect the call connection and the transmitter may "hang" for an indefinite period of time, unless the Mobile Activity Timer is enabled and the call will disconnect after one minute of not seeing. It is recommended to use the Mobile Activity Timer when using the VOX mode.

The above description of the VOX mode does not apply to the first 20-seconds after the patch is activated. During this period, the patch always defaults to the Sampling mode. This assures the mobile the ability to disconnect a call in the event of a busy signal or other telephone line audio that may occur on the onset of the call.

Making a Mobile to Landline Call Generally, dialing is easiest if you dial the telephone number immediately following the "*" command to connect. If you prefer to hear dial tone after connecting, and using the simplex Sampling mode, then hold the first digit of phone number for a couple of seconds to capture the patch before proceeding. In simplex VOX mode, if you need to hear dial tone you will have to hold the first digit for up to 8-seconds, or make a minor modification that will shorten this time (see Sampling Time in Appendix B).

Receiving a Landline to Mobile Call If reverse patch mode is enabled, you may receive an incoming call from the mobile(s). Each time the incoming call rings, it will cause Personal Patch to transmit a tone to the mobile. To answer the call: Press the "*" key on the microphone or encoder.

Conversing During a Call In the half-duplex mode, the mobile may transmit at any time and be heard by the landline party.

In simplex systems that are using the Sampling mode control, the mobile must key up and wait for the next sample period to occur before speaking. If there is no audio from the phone line this will only take a brief period - about 1-second. If you need to break into an ongoing period of voice from the landline party (or dial tone, busy signal, music, etc) then you will have to wait a maximum of 8-seconds before speaking or disconnecting. The reason sampling occurs less frequently during landline to mobile audio periods is so that the sampling interrupts (that can be heard by the landline party as short bursts of noise) are minimally distracting to the telephone conversation.

In simplex systems that are using VOX mode control you must wait for the telephone line party to stop speaking before the mobile can transmit and be heard.

Disconnecting a Call

To disconnect a call dial the "#" digit. In half-duplex mode, this can be done at any time during the call. In simplex Sampling mode you can accomplish this at any time, but the "#" digit must be keyed for at least 1-second when no telephone line audio is present, or up to 8-seconds if continuous audio is occurring. In the simplex VOX mode you may send the "#" digit only when the base station is not transmitting. If continual audio becomes present, keeping the transmitter on the air, simply wait one minute for the mobile activity timer to automatically disconnect the call (Mobile Activity Timer enabled).

Manual Operation

The "Connect" switch on the front panel provides a means to manually connect the phone line to any mobile, even one without DTMF capability. To invoke an outbound call, dial the desired telephone number from an extension telephone (connected to the Personal Patch line) and at an appropriate time, press the Connect switch. On an inbound call, press the Connect switch at any time. To disconnect the patch, press the Power switch OFF and then press again to turn the Personal Patch back on.

Automatic Mobile Activity Timer

The Personal Patch is designed with a timer that will disconnect a call in progress after 1-minute if the mobile has not been received for that period of time. This is a feature that prevents the patch from keeping the base station from being continually kept in transmit in the event that a mobile moves out of range or fails to disconnect for any other reason. You may disable this feature by removing jumper JP9, but is not recommended, and in particular when using the simplex VOX mode.

In Case of Difficulty

Unit appears dead or non-functional

(1) Remove the top cover and check fuse F1. Replace with 1.0 Ampere fast-blow type.

(2) Verify that approximately +12 VDC is present at J2-4.

(3) Verify that the ground connection is properly made at the base station and J2-5.

Mobile cannot connect ("*") or disconnect ("#")

(1) Verify that the mobile DTMF encoding is working properly (3.0 KHz deviation).

(2) Recheck the setting of RV3 (Installation section).

(3) Verify that the Noise LED is off when the mobile is transmitting and illuminated with not transmitting. Readjust RV4 as necessary.

(4) Verify that jumper JP7 is set correctly for the receive audio and COR method used.

Mobile is unable to transmit - base station always transmitting (Simplex VOX mode)

(1) Recheck the adjustment of RV1 (see Installation section).

(2) Verify that the telephone line is free of hum or other residual noise.

(3) Verify that the patch is set for the proper jumper configurations for this mode.

(4) Verify that jumper JP7 is set correctly for the receive audio and COR method used.

Mobile is unable to transmit - base station always transmitting (Simplex Sampling mode)

(1) Verify that the patch is set for the proper jumper configurations for this mode.

(2) Verify that the Sampling Rate is set correctly (RV5).

(3) Verify that jumper JP7 is set correctly for the receive audio and COR method used.

Noise LED does not function (Discriminator or Detector Audio used)

(1) Ensure that jumper JP7 is set correctly for this method (across Pins 2 & 3).

(2) Readjust RV4 in accordance with the procedure in the Installation section.

(3) Using an oscilloscope, verify that detector noise is present at J2-2 and that noise disappears when a mobile is transmitting (voice audio only).

Transmitter audio or modulation too low or too high

(1) Recheck the adjustment of RV2.

(2) Change the position of jumper JP1, and readjust RV2 for the correct deviation.

(3) Locate another connection point to the transmitter, and repeat steps 1 & 2.

Transmitter does not key

(1) Check the connection at J2-3 and the base station point of connection for PTT.

(2) Verify that the base station requires a logic low (ground) to transmit.

One or more functions are not operational

(1) Return all jumper settings to the factory defaults (see Summary of Jumper Configurations).

(2) Review the Installation section and compare with the radio or repeater schematic diagram and service manual.

(3) If installing for CTCSS, bypass this function for the time being and accomplish a 'basic' installation first with only the 'five connections', confirm proper operation with carrier squelch, and then proceed with the interface with the CTCSS decoder.

If difficulty is still experienced after addressing the above suggestions and the technical information contained in the Appendices of this manual, contact CES Customer Service Department for assistance.

Appendix A

How To Locate Discriminator or FM Detector Audio

Most receivers used in conjunction with CES Simplex Interconnects will likely have an integrated circuit FM detector, where the detected audio will appear on one pin of the IC. This pin will normally exit to the receiver's squelch circuit (sometimes part of the same IC) and to an audio amplifier incorporating de-emphasis (removes the high-frequency noise components) and/or and audio switch controlled by the squelch circuitry. In interfacing to an interconnect, several factors should be considered: (1) That connecting any external circuit to the IC does not load or affect it's operating characteristics, and (2) that any other external noise or RF is not permitted to be coupled back into the receiver. Locate the IF/Detector or Detector IC in the radio schematic. Verify with an oscilloscope that the pin contains both unsquelched high frequency noise (300 mV to 2 V typical) and only detected audio when receiving a modulated carrier. Connect the CES interconnect's Receiver Audio input to this point and note if the level is affected. If it becomes reduced by more than 20%, try placing a 10K to 20K resistor in series to minimize any loading. If necessary, use a higher value resistor. Place heatshrink tubing over the resistor and the connections to prevent any chance of shorting to surrounding components. If unusual noise is observed either in the radio speaker or interconnect when either is used, then an RF choke of perhaps 1 mH in series and at this point of connection may be needed.

The table later in this appendix lists several types of applicable detector IC's. If the IC type is not listed, and you are unable to determine the proper pin on the detector IC on the radio schematic:

Use an oscilloscope to locate the detected audio output. With no carrier being received, look for a pin that has high frequency noise (up to approx. 10 KHz or greater), and that has detected audio when receiving a modulated carrier. The audio level at the correct pin will not be affected by the receiver squelch control or the volume control. The correct pin will not normally be connected to a tunable coil, crystal filter, or ceramic resonator.

If the detector IC output pin cannot be determined, then proceed with the following suggestions:

(1) In no case will true FM detector audio be available at the speaker output connection of the receiver. Similarly, it is unlikely that the desired FM detector audio will be available at the 'top' of the receiver volume control. The recovered audio at these points will normally already be de-emphasized and will not include the high-frequency noise components necessary for most simplex interconnects to operate in this mode.

(2) The correct point will be somewhere between the 'top' of the front panel volume control and the detector IC. Looking at the radio schematic diagram, an FET audio gate may be seen with its' gate connected to the squelch circuitry. Verify with an oscilloscope that audio is always present at this point, even when the squelch control is set to squelched (no audio is heard from the speaker). With an RF signal generator or communications service monitor, generate a full-quieting on-channel carrier modulated with a 1 KHz tone.

After verifying the presence of the 1 KHz tone, vary the modulated tone upward to 10 KHz. If the recovered audio signal observed stays at approximately the same level, then make the discriminator audio connection to this point. If the level drops to a substantial level below that observed at 1 KHz, such as 30% or less, then move to a point in the schematic diagram toward the FM detector where the level of noise and recovered audio, including the 10 KHz test, are approximately the same.

Common FM Receiver IC's:

 

*Note: Some of the IC's listed above, in particular those marked with an "*", may have the detected audio pin squelched when a carrier is not being received. If this is the case, then the receiver must be left unsquelched at all times, or the External COR function must be used.

Appendix B

Customizing Timing Parameters Although the Personal Patch is designed with operating characteristics that meet most requirements and for optimum performance, many of the timing parameters can be easily changed by replacing a resistor or capacitor with a different value. To change a given timing parameter simply use a new resistor or capacitor value that is proportional to the change in time duration desired. For example, to decrease the mobile activity time from 60 seconds to 30 seconds, replace the applicable resistor or capacitor with a value that is one-half of the existing value.

The following is a list of timing parameters that can be changed:

Appendix C

Understanding Carrier Operated Relay (COR)

Although the preferred method for interfacing a simplex interconnect is using Discriminator or Detector Audio, where internal COR mobile detection is used, it may not be possible in cases where this audio is only available as squelched-controlled audio in the receiver.

If this is the case, then External COR must be used as an input to the CES Interconnect you are installing. Using the receiver schematic diagram, determine the circuit that derives the squelch logic and verify that the signal is a DC level change of 0 to 5 or more volts from a no-signal to a received signal condition. This can also be simulated by operating the squelch control. It is not important whether this active state is high or low, since all CES simplex interconnects can be configured for either one. Note the logic level (an active high or an active low) when the receiver squelch is "open" (unsquelched or receiving a carrier). This is the active logic level that will be used in configuring or programming the interconnect. Note: This logic signal must change very quickly in conjunction with receiving a carrier and when the carrier drops. In some receivers there are similar functions that may be used as a signal strength indicator, and are DC levels that change too slowly, or that change proportional to the received signal level, and are not suitable to serve properly as COR logic. Do not use this type of logic. Often, these outputs are labeled on the radio schematic as "S-Meter," or similar descriptions.

If you are not able to determine a direct source for squelch logic, and if the radio has a "busy" LED indicator, then the logic signal applied to the LED may be suitable for COR. In some circuits, the LED may be turned on with an open collector transistor to ground. If this is the case, the interconnects COR connection would be made to the collector and would be an active 'LOW' logic state. In other cases, the LED may be illuminated by a transistor switching a source current path to the LED. In this case, connect the COR lead from the interconnect to the high side of the LED and is a 'HIGH' active state when carrier is received.

Do not get discouraged, the receiver connection of a simplex telephone interconnect is the most complex aspect of the installation. You can call CES Technical Support during business hours (Telephone: 407-679-9440 M-F 9 AM to 5PM EST) and we will assist you as much as possible.

If you do not feel comfortable working on your radio or looking for connection points inside of the radio, we offer installation of our equipment to most radio models. Please contact the CES Sales Department for current rates and instructions.

Model 410 Personal Patch Parts List

 

 

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