Ericsson MPI-II VHF Instruction Manual Page 1

Mobile CommunicationsSERVICE SECTIONFOR MPI-II VHF PERSONAL RADIOPrinted in U.S.A.Copyright January 1991, Ericsson GE Mobile Communications, Inc.Maint

2. A full charge cycle using an appropriate Ericsson GEcharger.3. This procedure should be repeated again. Performingthe rated discharge and charge cy

INTRODUCTIONThis service section contains the necessary informationto align and troubleshoot the MPI-II (136-174 MHz) Per-sonal Radio. This manual inc

FRONT COVER1. Remove the battery as described in the previoussection.2. Remove the two screws at (A) (See Figure 2).3. Carefully lift the front cover

Several tests are presented which will help isolate a pos-sible RF or control circuit problem. The control circuits, whichare located on the T/R Board

Figure 4 - Location of Tuning Controls and Test PointsLBI-38557 LBI-385574

2. Check power on the lower channel. Adjust C124 in thedirection that increases power output to a level half waybetween the initial lower and upper ch

3. Check for proper operation of the synthesizer. Thereshould be approximately 0 dBm drive level on theSYNTH output line for proper transmit operation

D.C. AnalysisBattery voltage (7.5/10 Volts, B+) is supplied to a 5.4 voltregulator circuit consisting of transistors Q801, Q802 andQ803. Diode regulat

SURFACE MOUNT COMPONENT REPLACEMENT1. "Tin" one terminal end of the new component and thecorresponding pad of the PWB. Use as little soldera