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SURFACE MOUNT COMPONENT REPLACEMENT
1."Tin" one terminal end of the new component and the corresponding pad of the PWB. Use as little solder as possible.
2.Place the component on the PWB pads, observing proper orientation for capacitors, diodes, transistors, etc.
3.Simultaneously touch the "tinned" terminal end and the "tinned" pad with the soldering iron. Slightly press the component down on the board as the solder liquifies. Solder all terminals, allowing the compo- nent time to cool between each application of heat. Do not apply heat for an excessive length of time and do not use excessive solder.
With a
CAUTION
Some chemicals may damage the internal and ex- ternal plastic parts of the
4.Allow the component and the board to cool and then remove all flux from the area using alcohol or another GE approved flux remover.
If a
MODULE REPLACEMENT
The modules, all of which are located on the Synthe- sizer Board, are very reliable devices. Before replacing any of the modules, check the associated circuitry thoroughly to insure there is not a problem elsewhere. If replacement is necessary, follow the below procedures.
All of the component lead holes on the Synthesizer Board for the modules are plated through from the top to the bottom of the board. This allows for easy removal and replacement of the modules as long as appropriate soldering techniques are observed. Always observe static precautions when handling the board during module replacement.
To remove a module, position the Synthesizer Board in a work vice (face down, chip components up) and remove the solder from the
To install a module, clean any solder from the plated through holes and clean all flux from the board. Next, install the replacement module making sure that all pins align in the proper holes on the Synthesizer Board. Resolder the pins to the board. Clean the flux from the board using an approved solvent and clip any excess lead length.
5.Check the receiver sensitivity.
6.Check receiver audio.
7.If not using speaker/microphone, be sure the Accessory Jack Cover is securely in place.
BATTERY INFORMATION
The
Table 3 - Battery Drain
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| 2 WATT RADIOS | 4 WATT RADIOS |
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| 7.5 VOLTS | 10 VOLTS |
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| Receiver | 36 mA | 36 mA |
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| Standby |
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| Receiver | 200 mA | 200 mA |
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| Full Audio |
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| Transmit | 750 mA | 1050 mA |
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REDUCED CAPACITY
1. The battery is continuously overcharged for long peri- |
ods of time. |
Figure 9 - Typical
SURFACE MOUNTED INTEGRATED | PREVENTATIVE MAINTENANCE |
CIRCUIT REPLACEMENT |
2. A regularly performed duty cycle allows the battery to |
expend only a limited portion of its capacity. |
Figure 10 - Alternate IF Option
Soldering and
The
As preventative maintenance to insure that the radio is always operable, regularly schedule the following checks to be made on each radio.
1.Check the condition of and clean electrical connec- tions such as antenna, battery and battery charging contacts.
2.Check RF power output.
3.Check the transmit frequency.
4.Check the transmit modulation.
If the
The most common method of causing this limited capacity is regularly performing short duty cycles; when the battery is operated so that only a portion (50%) of its capacity is ex- pended. This type of operation can cause the battery to become temporarily inactive and show a severe decrease in the ability to deliver at full rated capacity.
Any
1.Discharge the multicell battery at the normal discharge rate until the output voltage is approximately 1 volt per cell. For
Refer to the typical
8