Park Air Systems Limited B63300HS User Manual

T6T 300 Watt VHF Transmitter

Page 100

Maintenance

Park Air recommends that scheduled maintenance is carried out at twelve-monthly intervals. Scheduled
maintenance comprises the following checks:

Remove all dust and dirt from the equipment exterior using a lint-free cloth and camel hair brush. Check
all external connections are secure and free from damage.

To set the transmitter internal reference frequency, use the following procedure. Note that references to
the switch in the procedure mean the Scroll/Select switch.

(6)

Turn the switch clockwise until Exit is highlighted, then press the switch. You are returned to the
Main screen. 

(7)

Disconnect the frequency counter.

(8)

If 5-offset carrier operation is required, complete the procedure 

1

Ensure the equipment is clean and that external 
connectors are securely fitted.

Camel hair brush/clean lint-free 
cloths.

2

Check and reset (if required) the transmitter’s 
internal frequency reference.

VHF frequency counter.

3

Perform a BIT interruptive test.

4

Perform an ac and dc change-over check (if both 
supplies are connected).

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(1)

If the transmitter operates with 5-offset
carrier (that is, set with a 4 kHz or 8 kHz
offset) reset the offset to zero.

(2)

Connect a frequency counter to the front
panel Reference connector.

(3)

From the Main screen, press the switch to
display the Control screen. Turn the
switch until Settings is highlighted. Press
the switch.

(4)

Ensure the Settings screen is displayed.
Turn the switch until Ref Freq is
highlighted, then press the switch.

(5)

With Ref Freq selected turn the switch
clockwise or anti-clockwise until the
frequency counter reads 20.950000 MHz
±10 Hz, then press the switch.