Maxon Telecom SP210 - Manual (Page 25)

SP200/210 Maxon SP200/210 Radio
Issue 1.0 INSTALLATION, COMMISSIONING & ALIGNMENT
03/01 Page 4-11
Rx VCO
a. Select Channel 1.
b. Check that the VCO tuning voltage at
TP1 is >5.7V +/- 0.25V (VHF) or >1.0V
+/- 0.25V (UHF).
c. Select Channel 3
d. Check that the voltage at TP1 is <12.5V.
Tx VCO
a. Select Channel 1.
b. Set the PTT switch to on and check that
the voltage at TP1 is 1.0V +/- 0.25V
(VHF) or 2.0V +/- 0.25V (UHF).
c. Select Channel 3.
d. Check that the voltage at TP1 is <12.5V.
e. Set the PTT switch to off.
Note: If TP1 is below 0.6V or above 12.5V, in
any of the above tests, L203 may be adjusted.
L203 is covered in wax and therefore great
care will need to be taken when removing the
wax.
TCXO
a. Select Channel 2.
b. Set the PTT switch to on.
c. Using the frequency counter, adjust the
TCXO control, so that the transmit
frequency is within +/- 200Hz of the
required frequency.
d. Set the PTT switch to off.
If no further alignment is to be carried out, it
may be necessary to check the squelch
setting.
4.5.4 Squelch Sensitivity
The RF input level to open the squelch is
usually set in the range –123.5 to –117dBm
(0.15 to 0.3mV). The squelch should open at
a SINAD between 7 and 12dB (no CCITT).
The squelch should close between 2 and 4dB
of the value at which it opens.
RV2 sets the squelch level for 12.5kHz
channel spacing and RV4 sets the squelch
level for 20/25kHz channel spacing.
Note: RV2 MUST be set before RV4.
4.5.5 Transmitter Alignment
Power Adjustment
See Section 4.4.