User's Manual

RPT 633
Page 3 - 6 TM1184 Issue 1
VOX KEYING MODULE
General
17. The VOX keying module decodes encoder presented serial data and controls the
transmitter. Interconnection between the Transmitter PCB and VOX Keying PCB is
as shown in Figure 2.
Figure 2: Module Interconnection Diagram
Analogue Path
18. Analogue signals are input via external connector SK1 of the transmitter PCB and
internal connectors TL8 and TL9. The level is adjusted via RV1 (VOX keying
module PCB) and output is via connectors TL1 and TL2 to the speech input of the
transmitter PCB. This presents the correct audio level to the transmitter modulation
circuits.
Data Mode
19. Data signals are input via external connector SK2 of the transmitter PCB, buffered
by TR14 and then fed, via the internal connector PL1-4, to the VOX keying module.