Federal Signal Corporation PA300 Series 690009, Инструкции по установке, обслуживанию и эксплуатации

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correcting a malfunction, should any occur. For correcting a malfunction, should any occur. For
emergency replacement of any of the small compo-
emergency replacement of any of the small compo-
nents, care must be used when soldering. Heat easily
nents, care must be used when soldering. Heat easily
impairs transistors, capacitors and circuit boards. It
impairs transistors, capacitors and circuit boards. It
is therefore advisable to use longnose pliers
is therefore advisable to use longnose pliers or a or a
similar heat sink on the similar heat sink on the lead being soldered. lead being soldered.
If IC13 or C21 are replaced, it may be If IC13 or C21 are replaced, it may be neces- neces-
sary to adjust R57. With the Selector Switch set to sary to adjust R57. With the Selector Switch set to
MANUAL, hold the paddle switch in
MANUAL, hold the paddle switch in the SIREN the SIREN
position and adjust R57 for 1510 Hz position and adjust R57 for 1510 Hz
± ±
10 Hz at the 10 Hz at the
siren output. siren output.
B. B. Removal for S Removal for Servicing. ervicing.
When removing the chassis for servicing, When removing the chassis for servicing,
loosen the two hexagon head screws on the loosen the two hexagon head screws on the underside underside
of the unit, near the front edge. Slide the of the unit, near the front edge. Slide the entire entire
chassis out of the case as shown in figure 6-1. chassis out of the case as shown in figure 6-1.
C. C. Removal of C Removal of Circuit Board ircuit Board..
The PC board is secured to the chassis The PC board is secured to the chassis by by
four Phillips head screws. Unplug the four wafer four Phillips head screws. Unplug the four wafer
connectors and microphone before removing the
connectors and microphone before removing the
screws.
screws.
D. D. Replacement Replacement of Output Tra of Output Transistors. nsistors.
Failure of one or both of the Failure of one or both of the output transis- output transis-
tors (Q7, Q8) is usually the result tors (Q7, Q8) is usually the result of a defective of a defective
speaker (short circuited voice coil). Rebroadcast of speaker (short circuited voice coil). Rebroadcast of
unsquelched radio or music for long periods will
unsquelched radio or music for long periods will also also
have a detrimental effect on the output transistors, have a detrimental effect on the output transistors,
and is therefore not
and is therefore not recommended. recommended.
Federal recommends that both output Federal recommends that both output
transistors be replaced should only one device prove transistors be replaced should only one device prove
to be defective. This practice will ensure long periods
to be defective. This practice will ensure long periods
of service between failures.
of service between failures.
When installing new output transistors, When installing new output transistors,
ensure that the Sil-Pad insulators are installed ensure that the Sil-Pad insulators are installed
between the heat-sink and transistors.
between the heat-sink and transistors.
CAUTION CAUTION
Make certain that the speaker is not defec- Make certain that the speaker is not defec-
tive prior to installing the repaired PA300.
tive prior to installing the repaired PA300.
6-3 6-3.. TE TEST STING ING AF AFTE TER R SE SERVI RVICE CE..
WARNING WARNING
All effective sirens and horns All effective sirens and horns produce loud produce loud
sounds (120 dB) that may cause permanent sounds (120 dB) that may cause permanent
hearing loss. Always minimize your exposure
hearing loss. Always minimize your exposure
to siren sound and wear hearing protection.
to siren sound and wear hearing protection.
Do not sound the siren indoors or in enclosed
Do not sound the siren indoors or in enclosed
areas where you and others will
areas where you and others will be exposed to be exposed to
the sound. the sound.
After installation; test the After installation; test the electronic siren, electronic siren,
including horn operation, to ensure that it is including horn operation, to ensure that it is operat- operat-
ing properly. ing properly.
After testing is comp After testing is complete, provide a cop lete, provide a copy of this y of this
manual to all operating personnel. manual to all operating personnel.
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