OK?..manual is complet and helpfull... for repairing such a old and rare boombox like JVC PCM it is necessary...
Text excerpt from page 15 (click to view)
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2-3. Error Messages
When a problem occurs, one of the following error messages may appear on the display.
Messages Error 11 Contents An error occurred in backup memory data. Measures The data was initialized. Set the transmitting channel frequency, the audio gain level, the compander time constant and RF output power again. Check the PLL synthesized circuit (IC402, CP401, and its peripheral circuit) on MB-914 board. Don't exceed 4.2 V.
Error 21 Error 31
The PLL synthesized circuit is in trouble The battery voltage exceeds the allowable value.
