Multitone RPR 551IS - Page 85

ARE DC LEVELS
CORRECT FOR THE RF
AMP? SEE TABLE 3
PLACE THE MAIN BOARD ON THE P637, POSITION B, AND
CONNECT IT TO THE RADIO BOARD VIA THE 4-WAY
EXTENSION LEAD. FIT A BATTERY. POWER UP THE
RADIO BOARD BY CONNECTING A LINK BETWEEN PINS 1
AND 4 ON SK2
REPLACE C314, INSERT AN ON-CHANNEL SIGNAL
MODULATED WITH 1kHz ON THE LIVE SIDE OF C327 AT A
LEVEL OF 1mV
IS I/P LEVEL >90dBm
FOR 12dB SINAD?
CHECK:
L304, R306, C320,
C325, C330, R308
CAN C314 BE ADJUSTED
TO GIVE A PEAK IN THE
O/P AT SK2 PIN 2 >20mV?
CHECK:
C317, C318, C319,
C336, C322, C323,
YES
NO
YES
NO
REMOVE SCREEN
AND C314
ARE DC LEVELS
CORRECT FOR TR304,
TR305, L307, XL301?
CHECK:
TR301, TR302 AND
ASSOCIATED
COMPONENTS
CHECK:
TR304, TR305 AND
ASSOCIATED
COMPONENTS
NO
YES
NO
YES
OSCILLATOR WORKING. REMOVE
C327. INJECT ON-CHANNEL SIGNAL
VIA 47p CERAMIC CAPACITOR AT
TR301 BASE
CHECK:
C317, C318, C319,
C336, C322, C323,
C329
RADIO BOARD OK. RECONNECT:
C327, SCREEN, AERIAL PARTS. RE-ALIGN
PAGER. RE-CASE. SEND CALL
E (RPR 553IS RADIO BOARD)
RPR 550IS Series
TM1188 Issue 1 Page 5 - 15
Figure 4: Fault-Finding Guide
(Continued)