RELM WIRELESS CORP. - BK RADIO DPHX51 User Manual

   

12                                                                                            BK Radio 

1.  Turn the Squelch knob on (clockwise) and 

monitor the Channel Guard channel before 
transmitting, or, if Busy Channel operation is 
enabled, check the yellow LED.  

NOTE:  Do not transmit if the channel is 

busy. 

2.  Press the PTT switch. When the transmitter 

is on, the red Transmit Indicator glows and 
TX appears in the display.   

3.  If monitoring the channel,

reset the squelch 

knob

to the Channel Guard position to 

receive only the messages with the proper 
Channel Guard value. During extended 
transmissions, the squelch can be left open 
until the exchange has ended.

   

The receiver and transmitter are capable of 
operating in analog wide-band (25 kHz 
channel spacing), analog narrow-band (12.5 
kHz channel spacing) and APCO Project 25 
Digital Mode. 

Each channel’s Receive and Transmit Mode 
can be set independently as follows:   

Analog Receive 

qualified 

analog signals 
only  

Transmit analog 
signals only 

Digital Receive 

qualified 

digital signals 
only 

Transmit digital 
signals only 

Mixed Automatically 

receive qualified 
analog or digital 
signals 

Transmit analog or 
digital signal, 
depending on the 
status of ‘TX 
Digital’ soft switch.  

Digital receptions and transmissions will be 
indicated by illuminating the ‘ID’ annunciator in 
addition to the ‘RX’ or ‘TX’ annunciator. 

 

Analog 

Operation 

               RX  

 CH          12 

          TX  

 CH          12 

Digital 

Operation 

            RX       ID  

 CH          12 

          TX          ID  

 CH          12 

 

Busy Channel 

 Indicator 

DPH Owner’s Manual                                                                           33           

The transmit Time-Out-Timer limits the 
duration of calls and guards against 
accidentally locking on the transmitter and 
tying up the radio system. Your dealer can 
program the duration of the Time-Out-Timer 
(15–225 seconds, or disabled). 

If the radio has been programmed for Busy 
Channel operation, it will operate in one of the 
following three Modes: 

• 

Busy Channel Indication 

• 

Busy Channel Lockout 

• 

Busy Channel Lockout Override 

 

The yellow Busy Channel Indicator glows if 
there is carrier activity on the selected 
channel.  If the selected channel is a Channel 
Guard channel and the proper Channel Guard 
value is not detected, the Busy Channel 
Indicator remains on for the duration of the 
carrier activity and no message is heard. 
During Scan and Priority Scan operation, the 
Busy Channel Indicator glows when activity is 
detected on any channel on the Scan List.  

When scanning or priority scanning Channel 
Guard channels with the Squelch knob in the 
Channel Guard position and activity has been 
detected, the Busy Channel Indicator glows 
for the time period necessary to determine if 
the proper Channel Guard value has been 
received. This will cause the Busy Channel 
Indicator to flash at various rates.