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UPX-300
Universal Port Extender

Turns any Single Controller Port		+8 to 18 VDC @ 20 mA*
Into Two Full or Half Duplex Ports
		Built in DSL-100 Circuitry
Multi-Port Interface for Links,
Repeaters, and Controllers		- 3 dB BW 50 Hz to 10 kHz
		Frequency Response
Ports Configured via 3 bit
Control Lines or DIP Switch		Full Status LED's for COS
		and PTT on all Ports
Easy Front Panel Access, Test
Points, and Adjustments		Optional Plug-ins for Stand
		Alone 2 Port Voter or 3
		Port Controller (3/2001)

The UPX-300 Universal Port Extender is an extremely versatile multi-port interface for radio repeaters, links, remote bases, and controllers.   The Universal Port Extender can be configured as an extender to an existing repeater controller when an additional port is required.  The UPX-300 can also be configured as a hub for three radios.   The radios can be a repeater with a controller, two links, two remote bases, or three links.  Many different configurations can be obtained with the Universal Port Extender.  The Universal Port Extender has the options for plug-on boards to transform the UPX-300 into a stand-alone three port controller or a two port repeater voter.

Typical Applications

Power Requirements*

The UPX-300 operates on any voltage between positive 8 VDC to 18 VDC.   The current draw is 20 mA when the LED’s are rendered inactive (via DIP switch) and 180 mA if all LED’s are on.  Power is connected to the unit via a 9-pin female D-Sub connector at P1 (Port D).  Pin 1 = + VDC and Pin 9 = Ground.  An internal, standard automotive 3AG, 1/2 amp fuse provides the necessary short circuit protection.

Connecting Ports Together

The UPX-300 can patch any of the ports together.  For example, Port A to B, Port A to C, Port B to C, or all together.  The Universal Port Extender has the provisions for external control of patching the ports together.  For example, an external controller can control which ports are to be connected at any time.  This is accomplished by providing an active low signal from a controller to an input to P1 on the UPX-300.

By configuring an external controller with DTMF macros and using the controllers universal digital outputs, the UPX-300 ports can be remotely controlled.  Port selection can be obtained by using the onboard DIP switch bank S1.  Port connection is defined as: connecting COS; Tone Squelch; PTT; RX and TX audio. 

In a linked system of repeaters, the UPX-300's Ports A and B could be connected as Links, while a local repeater controller can "tap" into the link using port C.  This is just one way of using the UPX-300.

Port Monitoring and Tone Squelch

The UPX-300 can be configured to have Port C monitor either of the other ports or both of them for DTMF control tones.  This feature allows port monitoring without having any port fully connected to each other. 

The Universal Port Extender also provides for CTCSS tone squelch at Ports A and B, or it can pass the tone squelch signal to a controller at port C, or both functions at the same time.  The ports COS signal will not go active unless the ports tone squelch is also active.  This is easily configured by jumpers on JP12.  To configure port C as a radio port instead of a controller port, all that is required is to jumper pins 3 to 2 on JP12.  This changes the C port tone squelch from an output signal to an input signal.  The onboard requirement for tone squelch is configured by DIP switch bank S4.  Port C tone squelch cannot be passed on to Ports A or B.   It controls the COS signal on port C becoming active.

Tone Squelch

The onboard requirement for CTCSS tone squelch is configured by a DIP switch.  When the DIP switch enables the tone squelch option, both the COS and CTCSS tone squelch inputs on the specified port must be active in order to activate the port's internal UPX-300 COS logic.  Both inputs are active low at the Port's DB9 connector.

Port C as a Radio or Controller Port

Port C of the UPX-300 is specially designed to act as just another "radio port" (just like ports A and B) or it may be configured as a "controller port".  This is easily configured by a  jumper.

When Port C is configured as a "radio port" (jumper pins 3 to 2 on JP12), it's CTCSS tone squelch pin is an input to the UPX-300. In this case, Port C's CTCSS input is gated with it's COS input. 

When Port C is configured as a "controller port" (jumper pins 1 to 2 on JP12), it's CTCSS tone squelch pin is an output from the UPX-300 to your controller; and if the CTCSS input on either Port A or B becomes active, it is routed to Port C's CTCSS tone squelch pin (providing Port A or B is actually connected to Port C).   The CTCSS tone squelch signal on Ports A and B is always an input.

Monitoring Ports A and B by Port C

The UPX-300 can be configured to have Port C monitor either of the other ports or both of them for DTMF control tones.  This feature allows monitoring Ports A and B without having any port fully connected to each other, i.e. the PTTs of Ports A and B  won't be engaged by an active COS input on Port C (when Ports A and B are disconnected from Port C).  This allows DTMF control signals coming from Port A or B to be processed by what ever is connected to Port C.

Status Indicators

The Universal Port Extender has seven LED’s which provide operational status.  Ports A, B, and C active COS (Green), PTT (Red), and Power (Yellow).  As mentioned, all of the LED’s can be turned off to conserve power via a DIP switch.

Duplex Operation

The normal operation for each port is full duplex operation where each port can receive and transmit at the same time.  Provisions for special radio requirements, such as remote bases and simplex radio links, have been included on the UPX-300.  Each Port can be configured as a half duplex port.  When the port is receiving a COS signal, the PTT cannot be activated until the COS on the same port goes inactive.  Any other port attempting to send a PTT command to a port configured as a half duplex port will not be able to signal a PTT command on the half duplex port until the half duplex port’s COS goes inactive. 

Port Hangtime

Ports A, B, and C can be configured with a variable hangtime for PTT.  The only restriction is that all ports must have the same duration of hangtime.  Hangtime is selected with switch bank S4 switch 4 (closed) = hangtime on.  When a repeater controller is connected to port C of the UPX-300, the controller usually provides a PTT hangtime and the hangtime switch should be turned off.  If additional hangtime is desired, the hangtime on the UPX-300 can be active.  This will provide an additional hangtime.   Hangtime on half duplex links may be useful to eliminate the “Ping-Pong” effect between two half duplex linked systems.  The hangtime can be varied from approximately ½ second to 5 seconds.  A trimpot, VR7, adjusts the hangtime required.   

Timeout Timer

The "Timeout Timer" can be configured for a PTT timeout on all ports for an adjustable duration of 1 to 7 minutes, or no timeout.  The timeout time is programmed via DIP switch bank S4 switches 1, 2, and 3.  The programming is in BCD format, i.e. 1, 2, 4.  If all three switches are programmed for a zero time, there is no timeout.    It is recommended that a timeout time be programmed to prevent an open squelch on a link, for example, from causing a continued PTT command on a port.

Port Connections

Ports A, B, and C are 9-pin female D-sub connectors and are pin compatible to LinkComm or other controllers.  The only difference is that pin 1 of these connectors can be configured with either Ground or +12 VDC.  The +12VDC is current limited by the main fuse and can provide a maximum of 200 mA.

Pin assignments:

Pin 2 = Tone Squelch (Active Low).
Pin 3 = PTT (Active Low) Maximum Current 200ma.
Pin 4 = TX Audio
Pin 5 = RX Audio
Pin 6 = Ground
Pin 7 = COS (Active Low)
Pin 8 = TX Audio Ground
Pin 9 = RX Audio Ground

Receive Audio Configuration

The receive audio can be adjusted over a wide range of levels.  A range low/high switch selects radio input levels from (Low) 100 mV P-P to 1 V P-P, and from (High) 400 mV P-P to 7 V P-P. The receive level can be easily accessed and adjusted via the front panel controls. The impedance on the Low Range is 10 K ohm and 100 K ohm in the High Range.  The frequency response is 50 Hz to 10 kHz @  –3dB points.  Test points are provided at the front panel to set each ports receive audio level to the internal audio buss of the Universal Port Extender.  The level at the RX Audio Test Point should be set to 1 volt peak-peak.  If the port is connected to a narrow band FM radio receiver, the receiver should be sent a 3 kHz modulated signal with 1 kHz tone.   You can easily monitor the appropriate test point with an analog meter or oscilloscope, and adjust the corresponding receive audio control for 1 V P-P.

Receive de-Emphasis

The receive audio from any port connected to a radio receiver’s detector output, can be configured with a 6 dB per octave de-emphasis network.  This configuration is for narrow band FM receivers only.   This is easily accomplished via the DIP switch bank S3 & S4 either closed or open enables or disables de-emphasis.

Transmit Audio Configuration

The transmit audio can be adjusted over a wide range of levels.  A range low/high switch selects the range required by a radio transmitters audio input.  The range low/high switch selects levels from (Low) 100 mV P-P to 1 V P-P, and from (High) 400 mV P-P to 5 V P-P into a 600 ohm load.
The transmit level can be adjusted via the front panel controls and the transmit level to each port can be monitored by the front panel test points.  The output impedance is 150 ohms, and the frequency response is 50 Hz to 10 kHz  @ –3dB points. 

Dynamic Speech Limiter

The UPX-300 has an exclusive feature called DSL (Dynamic Speech Limiter).  This feature provides automatic gain/attenuation for audio to be transmitted on ports A and B only.  If an audio signal is low, the DSL will bring the level up to the proper level set by the front panel TX Level control.  If the signal is too high, the DSL will bring the level down to the proper level.  The DSL will improve variations of audio levels on links and repeaters.  The attack time of the DSL is 500 micro-seconds, and the release time is 20 milli-seconds.  These time constants meet EIA/TIA telephony standards and will track syllables of speech.  The dual built in DSL, is identical in specifications to the K²RF DSL-100.

 UPX-300 Specifications

Parameter	Symbol	Min.	Max.	Units
Operating Voltage   (12 VDC  Typical)	VSUP	8	18	VDC
DC Current Draw*	ISUP	20	200	mA
Input Impedance Low	ZINL	10K	10K	Ohms
Input Impedance High	ZINH	100K	100K	Ohms
- 3 dB Frequency Bandwidth	FBW	50	10K	Hz
- 3 dB BW Flat Response	FBWF	300	3400	HZ
Rx Audio Input	RXIN	0	7.0	VP-P
Tx Audio Output @ 150 ohms	TXOUT	0	7.0	VP-P
Cross Talk (port to port)	CT	-	- 60	dB
Noise Floor	NF	-	- 70	dB C
Temperature Range	TR	0	+ 40	° C

*200 mA when LED's are enabled

Mechanical Specifications

Default Jumper Configuration for JP3
(Above)

Default Jumper Configuration for JP4 and JP5
(Above)

Default Jumper Configuration for JP9 and JP10
(Above)

Default Jumper Configuration for JP9, JP10, JP11, and JP12
(Above)

 Link to UPX-300 Manual  (PDF)

 Link to UPX-300 Expansion and Port 1 Wiring  (PDF)

 Link to UPX-300 Silk Screen Diagram  (PDF)

AVAILABLE NOW

$195.95