Alignment Via Ibm Personal Computer; Description; Power Set And Current Limit Adjustment; Figure 12 Service Alignment Diagram - Motorola Spectra Service Manual

ALIGNMENT VIA IBM PERSONAL COMPUTER

I.

DESCRIPTION

Using an IBM PC, interface hardware, and associat-
ed software, field personnel can adjust the Spectra radio
for either periodic alignment or advanced alignment
required when a damaged or failed board is replaced.
Simple prompts guide the user through the alignment
procedures; the user need only know what procedures
to access and the order in which those procedures must
be executed.
Reference oscillator, high- and low-power, and devia-
tion adjustments may also be made from
the radio front panel without the IBM PC.
See FRONT PANEL PROGRAMMING AND
ADJUSTMENTS.
Standard alignment procedures (power-set and cur-
rent-limit adjust, reference oscillator adjustment, and
deviation alignment) are performed at the factory, and
should not be performed in the field unless field repairs
have been made. Software in the PC cautions against
advanced alignment (or post-repair alignment proce-
dures) except when board replacement has occurred.
(See Figure 12, Service Alignment Diagram.)
Table 10 details the procedures required, and the
sequence in which the procedures must be performed,
after each specific board replacement. No alignment is
required for parts replacement other than those shown
in the table.
After alignment, exit the "SERVICE" menu entirely (to
the "MAIN MENU") to save all changes properly.
Failure to do so can result in a "FAIL 01/82" or "FL
01/82" failure (see Table 11).
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NOTE
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INSERT GXW-4294-A
PICKUP FROM PG. 25
Figure 12. Service Alignment Diagram
II. POWER SET AND CURRENT LIMIT
ADJUSTMENT
1. Connect a power meter and a 50-ohm load (or ser-
vice monitor) to the antenna connector, using
minimum cable length and as few adapters as pos-
sible.
The power amplifier must be firmly mounted to the
transceiver for accurate power adjustment.
2. Connect dc power to the radio and switch radio
power on.
3. At the PC's "MAIN MENU" prompt, press F2 to
select "SERVICE."
4. At the "SERVICE" menu, press F2 to select "ALIGN-
MENT."
5. At the "ALIGNMENT" menu, press F7 to select the
TX High Power screen.
For basic tune-up, skip the following steps that are
preceded by an asterisk (*); perform all the following
steps after PA board replacement.
For 12-watt units, no current set is required.
5a. At the High Power Set screen press the down arrow
key to adjust the power-set relative value to 20.
(This prevents excessive initial power output.)
Microphone PTT should not be used during this pro-
cedure, as it may cause incorrect frequency
selection.
5b. Press F8, "PROGRAM VALUE," to save this value
in the radio.
NOTE
NOTE
NOTE