Options Installation; Mi Cr-338 High-Stability Crystal Unit; W Pll Reference Frequency Adjustment - Icom IC-707 Instruction Manual

OPTIONS INSTALLATION 8
Mi CR-338 HIGH-STABILITY CRYSTAL UNIT
The CR-338 improves the total frequency stability.
è Frequency stability : £0.5ppm (-10°TCto+60°C;
+14°F to+140T )
1) Refer to p. 33, remove the top cover and the
PLL unit.
2) Unsolder and remove the original crystal from
the PLL unit.
e Use a de-soldering braid.
CR-338
Original crystal
AZ K
Ire
3) Unsolder the 4 positions on the PLL unit where
the CR-338 is installed.
e Use a de-soldering braid.
4) Install the CR-338 in the PLL unit.
e Symbols on the bottom of the CR-338 MUST be
identically matched with symbols on the PLL unit.
5) Bend the leads of the CR-338 at the foil side of
the PLL unit and solder them.
6) Trim the leads even with the solder points.
7) Refer to the box below, adjust the PLL reference
frequency.
8) Replace the PLL unit and the top cover.
Wi PLL reference frequency adjustment
After optional CR-338 installation, PLL reference
frequency adjustment is required.
Adjust oscillation frequency 5 min. after power ON.
Adjustment <4
A points D
Oo
Connect a freguency counter and adjust oscillation
freguency.
: @ C16 on the PLL unit
(2) L4 on the PLL unit
Repeat steps () and ©.
e Measurement point : J30n the MAIN unit
e Oscillation frequency : 64.000 MHz
e Adjustments points
Measurement point