Midland XT511 Alignment Procedure

Midland XT511
1. REFERENCE TEST EQUIPMENT
• A. HP8921A Cell site test set or HP8920A, B Communication Test Set with
Spectrum
Analyzer option.
• B. Fluke 187 Digital Voltmeter
• C. HP E3615A Power supply
2. TEST POINT
A. ANTENNA
B. GMRS VCO reference voltage: Test point 1 is prepared.
C. RX audio output
D. TX Mic. Input
E. Battery Vcc
F. Call Key
G. Menu Key
H. Monitor Key
I. PTT Key
J. Scan key
Note. : All key can be activated when connect with ground.
3. VCO ALIGNMENT
A. Set unit to Channel 1 and connect a voltmeter to TP1 (VCO PD).
B. Press & hold PTT.
C. Extend L141 until the voltmeter reads 1.5V.
D. Put shield-can on VCO area and monitor the voltage on TP1. The voltage should be
1.5Vdc +/-0.2Vdc. If the voltage is not 1.5Vdc +/-0.2Vdc, realign L141 until meet to
requirement.
E. Release PTT button so units is in receiving mode and monitor the voltage on TP1. The
voltage should be in the range 1.5Vds +/-0.5V
F. Set unit to channel 14.
6. Press & hold the PTT switch and observe the voltage on TP1. The voltage should be 2 -
3,5 Vdc.
7. Release PTT and observe the voltage on TP1. The voltage should read between 2.0 - 3.5
Vdc.
Note : VCO shield-can should be soldered after VCO alignment is finished.
4. TRANSMITTER FREQUENCY ALIGNMENT
A. While Press & hold the PTT, Menu and Menu buttons, the knob clockwise to switch on
radio..
B. Align Up or Down button such that the output frequency is equal to the channel frequency
with a maximum error of +/- 200 Hz.
ALIGNMENT PROCEDURE
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: Test point is not prepared. Use antenna contact with
ANTGND1(antenna ground).
: Speaker terminals & ear jack are prepared.
: Use ear-jack(3.5mm) with 10uF coupling capacitor.
: Test point is not prepared. Please use mechanical contact.
Plus terminal is posited on upper right corner of PCB (Battery
cover side view).
: Test point UP is prepared.
: Test point MENU is prepared.
: Test point MONITOR is prepared.
: Test point PTT is prepared.
: Test point SCAN is prepared.
the