Product manual

Setting FFSK Levels in a Radio-based System
115
♦ Setting the Model 6 FFSK receive level:
1. At the Model 6 location, connect an oscilloscope to measure the receive audio
signal at TP-1 on the Model 6 motherboard. The expected signal will be
approximately 1.0 Vp-p (0.35 Vrms).
2. On the Model 6203 motherboard, turn R107 (4-wire Rcv) fully clockwise and
R135 (2-wire Rcv) fully counterclockwise.
3. Turn R62 (FFSK in) fully counterclockwise. Set R86 (VOX threshold) to the
middle of its range.
4. Call the Model 26 site and have the operator there initiate the FFSK Test signal
from the Model 26.
5. If the voltage measured at TP-1, while the test signal is being received, is less
than 1.0 Vp-p (0.35 Vrms), turn R62 clockwise until it reaches 1.0 Vp-p.
6. If the voltage measured at TP-1, while the test signal is being received, is greater
than 1.0 Vp-p (0.35 Vrms), turn R107 counterclockwise until it is reduced to 1.0
Vp-p (0.35 Vrms).
7. When finished making adjustments, let the test signal time-out or stop the test.
Table 8: Initial Model 6 Jumper Settings
Jumper Description Positions Align. Position
JP-1 Address line A14 to Ram Always A = Yes
A
JP-2 Special CPU Mode Always None
None
JP-3 Enable VOX Always B = Enabled
B
JP-4 AGC Applied to FFSK RCV Data Always A = No
A
JP-5 FFSK Transmit Level TEL, PWR, Radio TEL(PWR, RAD)
JP-6 Jumper over PA Relay Always None
None
JP-7 Jumper over PA Relay Always None
None
JP-8 600 Ohm 2W RCV Termination A = yes if this Model 6 Primary
A
JP-9 COR Pull-up A = Pull up, B = None
A
JP-10 600 Ohm 4W RCV Termination A = yes if this Model 6 Primary A(B)
JP-11 Digital Port Baud Rate 9600,4800,2400
9600
JP-12 Prtr/Pgmg. Port Pin 2 Function A = Std, B = Zetron Pin 4
B
JP-13 Digital I/F Port Pin 2 Function A = Std, B = Zetron Pin 4
B
JP-14 Source of Audio to PA A = Normal, B = Auxiliary A(B)
JP-15 600 Ohm Aux RCV Termination A = Yes if this Model 6 Primary
A