Adcon A440, Technical Reference Manual

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The A431 Radio Module
c. Frequency Deviation: ±1.5 kHz (±0.2 kHz)
3. Switch the unit to stand-by by pressing the Enter key.
For item 3.a above, adjust R75 (see Figure 17). For item 3.b, issue the command
PWR at the terminal and use the D (down) and U (up) keys until the required value
is reached. Finally, for item 3.c, issue the command BW at the terminal and again
use the D and U keys to reach the required value.
3.3.13. Data Transfer Check
The last check is a radio data transfer. In order to perform it, at least a base station
(model A730SD) or a remote station (model A733) must be installed and operated
on the same test frequency, in the near vicinity (no more than 30 m).
Note: The base or remote station used for this test must be operated with a fictive
antenna (a 50
Ω
resistor).
To perform the test, enter the command B at the terminal prompt: the base and/or
remote station must answer with the RF in and out values. If an answer is not re-
ceived after several seconds, retry the command. If an answer is still not received,
then use a scope on TP1 on the A733MB board (the Text Fixture) to verify that the
digital data is present (on receive). In addition, a radio receiver tuned on the oper-
ating frequency can also supply a rough indication of whether the receiver or the
transmitter is defective.