User Manual
MT-4E VHF & UHF Receiver & Transmitter Instruction Manual
IM08-MT-4E-TXRX Project 1106
Hardware Tuning and Troubleshooting
13
RECEIVER JUMPERS
Receiver Main Board
Jumper Default Position Function / Description
JU1 OUT When installed enables Clear Keys 1 Input
JU2 OUT When installed enables Clear Keys 2 Input
JU3 IN When installed enables power to Discriminator Output amplier
JU5 OUT When installed bypasses capacitance coupling on the Discriminator output
JU7 OUT When installed enables power to Discriminator Output LPF amplier
JU9 X X: 600 Ω Audio Transformer
Y: Bypass Transformer
JU10 X X: 600 Ω Audio Transformer
Y: Bypass Transformer
JU11 IN When installed enables power to Balanced Audio Output amplier
JU12 OUT When installed increases the gain of Balanced Audio Output amplier
JU13 OUT When installed selects 600 Ω resistance to ground
JU14 X X: 600 Ω Audio Transformer
Y: Bypass Transformer
TRANSMITTER JUMPERS
Transmitter Main Board
Jumper Default Position Function / Description
JU1 X X: A/D Front Panel Switch selects transmitter A/D mode
Y: A/D External Input selects transmitter A/D mode
JU2 Y X: MIC OUT connects to Microphone Audio Input
Y: MIC IN connects to Microphone Audio input
JU3 X X: 600 Ω Audio Transformer
Y: Bypass Transformer
JU4 IN When installed selects 600 Ω resistance to ground
JU5 IN When installed enables Clear Keys 1 Input
JU6 IN When installed enables Clear Keys 2 Input
JU7 X X: 600 Ω Audio Transformer
Y: Bypass Transformer
JU8 X X: 600 Ω Audio Transformer
Y: Bypass Transformer
JU9 OUT When installed bypasses capacitance coupling on the Subtone / Direct
Modulation Input
Jumpers are shown on the MT-4E Transmitter
Jumper and Test Point Locator Illustrations.