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Alignment

Introduction and Precautions

The

FT-7800R

has been carefully aligned at the factory

for the specified performance across the 144 MHz and 430
MHz amateur bands. Realignment should therefore not
be necessary except in the event of a component failure.
All component replacement and service should be per-
formed only by an authorized Vertex Standard represen-
tative, or the warranty policy may be voided.

The following procedures cover the sometimes critical and
tedious adjustments that are not normally required once
the transceiver has left the factory. However, if damage
occurs and some parts are replaced, realignment may be
required. If a sudden problem occurs during normal op-
eration, it is likely due to component failure; realignment
should not be done until after the faulty component has
been replaced.

We recommend that servicing be performed only by au-
thorized Vertex Standard service technicians who are ex-
perienced with the circuitry and fully equipped for re-
pair and alignment. Therefore, if a fault is suspected, con-
tact the dealer from whom the transceiver was purchased
for instructions regarding repair. Authorized Vertex Stan-
dard service technicians realign all circuits and make com-
plete performance checks to ensure compliance with fac-
tory specifications after replacing any faulty components.

Those who do undertake any of the following alignments
are cautioned to proceed at their own risk. Problems
caused by unauthorized attempts at realignment are not
covered by the warranty policy. Also, Vertex Standard
must reserve the right to change circuits and alignment
procedures in the interest of improved performance, with-
out notifying owners.

Under no circumstances should any alignment be attempt-
ed unless the normal function and operation of the trans-
ceiver are clearly understood, the cause of the malfunc-
tion has been clearly pinpointed and any faulty compo-
nents replaced, and the need for realignment determined
to be absolutely necessary.

Required Test Equipment

The following test equipment (and thorough familiarity
with its correct use) is necessary for complete realignment.
Correction of problems caused by misalignment result-
ing from use of improper test equipment is not covered
under the warranty policy. While most steps do not re-
quire all of the equipment listed, the interactions of some
adjustments may require that more complex adjustments
be performed afterwards. Do not attempt to perform only
a single step unless it is clearly isolated electrically from
all other steps. Have all test equipment ready before be-
ginning, and follow all of the steps in a section in the or-
der presented.

Regulated DC Power Supply: adjustable from 11.5 to
16 VDC, 10 A

RF Signal Generator with calibrated output level at
500 MHz

Frequency Counter: ±0.1 ppm accuracy at 500 MHz

AF Signal Generator

SINAD Meter

Oscilloscope

Spectrum Analyzer

Deviation Meter (linear detector)

AF Millivoltmeter

AF Dummy Load: 8-Ohm, 5 W

DC Voltmeter: high impedance

Inline Wattmeter with 5% accuracy at 500 MHz