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14
25A1090 (Rev.3)
ALIGNMENT PROCEDURE
Alignment and Measurement Procedure
The alignment procedure is sequential and does not change unless specified. Use RG58 or
other low loss 50 ohm cables for all RF connections. Type RG174 (thin) 50 ohm cables can be
used for short (e.g. 6 inch) runs. Keep RF test cables as short as possible. Include the insertion
loss of the cables and the connectors for all RF measurements. DC voltages are present at most
RF test points. Use DC blocks to protect the test equipment, if necessary. All audio analyzer fil-
ters should be OFF unless otherwise specified.
VOLTAGE REGULATION CHECK
With power applied properly, and the unit switched on, measure the DC voltages at the fol-
lowing test points. All test points are located on the top side of the PCB. Refere to the component
diagram.
INITIAL SETUP
1.
Proper adapters should be used to connect the test equipment.
2.
Apply +3 V to the battery terminals with the proper polarity.
3.
Set audio gain switch SW100 to "-10 dB".
4.
Remove L641 to disengage the antenna (
ALL EXCEPT JB
).
5.
Solder the center of a 50
Ω
unshielded test cable (PT1824) to the node between L606 and
L641, and the shield to ground.
6.
Connect the audio generator output to the Mic Test Head input of the transmitter as
required.
7.
Turn on the SLX2 by pressing and holding the POWER button, SW325
.
RF TUNING
The removal of L641 (prevents antenna loading of output).
VCO Tuning
:
1.
Set transmitter to its LOW frequency as indicated in the table above.
2.
WIth a DC meter probe TP_PLL_TV (top).
3.
Tune CV500 to obtain 1.10-1.40 Vdc at TP_PLL_TV. For Q4 units, this voltage should
read between 1.45-2.25 Vdc. For JB units, this voltage should read between 1.75-2.05
Vdc.
4.
Set the transmitter to HIGH frequency.
5.
Verify voltage at TP_PLL_TV is less than or equal to 4.3 V DC.
Test Points
Voltages
(Battery input)
3 ± 0.2 Volts
TP5V (Power Converter)
5 ± 0.2 Volts
TP3.3V (Power Converter)
3.3 ± 0.2 Volts
TPA1 (Audio Preamp)
2.5 ± 0.2 Volts
TPA3 (Tone Key Summing Amp,
(IC150 Pin 14))
2.5 ± 0.2 Volts
TPVREF (IC100 Pin 5)
2.5 ± 0.1 Volts
Frequency
Level
H5
J3
JB
L4
P4
Q4
R5
S6
LOW
GRP. 1 /
CH. 1
GRP. 1 /
CH. 1
GRP. 1 /
CH. 5
GRP. 1 /
CH. 1
GRP. 14 /
CH. 1
GRP. 1 /
CH. 1
GRP. 4 /
CH. 1
GRP. 13 /
CH. 1
MID
GRP. 4 /
CH. 7
GRP. 4 /
CH. 7
GRP. 1 /
CH. 2
GRP. 4 /
CH. 7
GRP. 14 /
CH. 5
GRP. 1 /
CH. 5
GRP. 4 /
CH. 7
GRP. 14 /
CH. 7
HIGH
GRP. 6 /
CH. 12
GRP. 6 /
CH. 12
GRP. 5 /
CH. 4
GRP. 6 /
CH. 12
GRP. 15 /
CH. 10
GRP. 1 /
CH. 8
GRP. 2 /
CH. 11
GRP. 3 /
CH. 13