RA-DR1XM Jumper Assignments:

Jumper Summary - 

JU1 - Controls Revert logic polarity - Set to "B" position for DR-1X.
JU2 - Audio amplifier powering - select between USB 5V and a external 12V source.
JU3 - DR-1X internal controls enable - Set to "B" position for DR-1X.
JU4 - Remove this jumper to enable PTT LED false illimination protection.
PTT - One of two jumpers to select transistor or relay PTT keying. See NOTE below.
PTT - Two of two jumpers to select transistor or relay PTT keying. See NOTE below.

NOTE:
The PTT keying method is selectable by two mechanical jumpers. You choose between Transistor or
Relay keying.  The selection between transistor and relay keying is done with a pair of 
two - 2-pin headers in a square arrangement.  These headers are red and require two jumpers 
to be placed in either a up/down or back/forth (vertical or horizontal) side-by-side orientation.
Both jumpers are required for the option to work correctly.  The up/down position selects the 
relay, while the back/forth position selects the transistor.  These headers are located in a 
square box labeled "PTT" near the relay.  If the relay position is selected - it's best to 
also place JU6 - but not required.  In the transistor position - select the position of JU6 
as required and detailed below.

JU1 and JU3 set up the Local Control function allowing the revert logic to switch to internal 
control. Local Control is a logic option that can enable the internal DR1X control method.  
If enabled, internal controls will allow the repeater to operate locally if the Asterisk 
application, computer, or RA-DR1XM should fail.  

Jumper JU2 - Audio amplifier powering.
Position A = Amplifiers powered from USB 5VDC. Suitable for many radio applications where 
the maximum required P-P voltage doesn't exceed 5 volts.
Position B = Amplifiers powered from external source 6 to 15 VDC. Some radios, like the 
Yaesu System Fusion, may require more than 5 volts P-P of audio. Many radios have a source 
of 10 to 15 volts readily available. Must be well filtered but regulation isn't necessary 
as long as enough current is available for the load. Driving speakers will require a power 
source capable of several hundred mA., depending on speaker impedance and desired listening 
level.

JU4 False PTT LED illumination protection:
Jumper JU4 is removed to enable this illumination protection.  The jumper can be 
placed if this option should it create a problem for a particular installation. 
The jumper simply shorts out the diode. Place this jumper when using the relay
PTT keying selection.

Why is it necessary?
Partial (or full) illumination of the PTT LED can happen if the radio adapter is
connected to a radio that has a PTT switching voltage (bias) of less than 5 volts.
This is the case with many portable radios.  This situation causes the red PTT LED 
to partially illuminate. This illumination can also happen with just about any radio 
when the radio's power is turned off, falsely making it look like the radio is 
transmitting. Placing JU4 disables the BAT43 diode protection.
Default is JU4 is removed, but place this jumper when using the relay PTT keying selection.