Note: This service bulletin is meant for technical per-
sonnel with experience working on solid state com-
munications equipment. Damage caused by im-
properly installing this modification may cause
ICOM to charge for subsequent repairs to the
product. ICOM does not warrant this modification.
Bulletin #: 00389-001
Date: January 3, 1989
Subject: When servicing the radio, the technician may cause
failure of the +5 V source by improperly replacing
crystal X-3. We have seen cases of this occur-
ring.
Information: When replacing reference crystal X-3, the physical
location of the crystal is critical due to close
spacing of coil L-17.
Procedure
1. Make sure the leads of X-3 are insulated with tubing to
prevent shorting. If a short does happen the VCO buffer
signal will be shorted to ground and cause PLL unlock.
2. It is suggested that the body of the crystal as well as the
leads be insulated to prevent contact with L-17 in the VCO
circuit.
3. Do not trim the leads of the replacement crystal as all of
the supplied length is required.
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