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Troubleshooting Guides: IC-730
Maintenance |
Though the IC-730 is a
good-performing, reliable radio, many of these units have been in service
for a number years and are beginning to show their age. The following
preventative maintenance procedures should be done to all IC-730's that
are in need of repair.
1.) |
On the RF unit,
resolder the J2 and J3 connectors. Due to the relatively thick coax
cables on the connectors, these solder joints tend to crack with age
and cause intermittent transmit and receive problems. |
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2.) |
Make sure the receiver
preamp works. If inoperative, replace relay RL1 on the RF unit.
Install the factory update to prevent relay failure. |
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3.) |
Check transistor Q5 on
the RF unit. If it is a 2SC945Q, replace it with the improved
2SC2878B to prevent spurious output from the transmitter and failure
of the driver transistors. If Q5 is a type 1636, it doesn't need to
be replaced. |
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4.) |
Clean the RIT pot and
switch with tuner cleaner. These controls are usually noisy and
erratic, making the RIT hard to use. |
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5.) |
Tighten the
chrome-plated PC board mounting screws. The screws and spacers tend
to come loose if the radio is used in a high-vibration, mobile
environment. Don't forget to tighten the screws on the logic and IF
units located beneath the main unit. |
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6.) |
Check the bandwidth
coupler for proper tightness. Tighten as needed. |
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