Motorola SABER RVN4002K User Manual

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(b) Before proceeding, you must have previously aligned the VCO and Reference

Modulation. If you have not done this yet, press ESC to return to the SERVICE menu,
then follow the instructions in the section "Align Channel." Upon returning to the
SERVICE menu, reselect "Align Radio" and proceed.

One additional requirement is that your radio must have a "KEY" loaded for coded
transmission. To check this, select a channel that is programmed (SLAVED) for coded
transmission or place the clear/coded switch in the coded position and key the radio. If
there is no key present, the radio will continuously emit short alert tones indicating a "key
fail" condition. On SABER models with a display, the key fail message will display as
long as the radio is keyed up.

NOTE

After aligning VCO, REF MOD and returning to the align radio screen, do not
change channels as this will result in the old tuning information being used.

The selected item will be highlighted in inverse video.

(d) Place the clear/coded transmission switch in the coded position.

(e) Connect the RF BNC connector to a 50 ohm load and to a service monitor ( with Secure)

so that you can measure deviation.

(f) Select the Secure function on the service monitor. Increase or decrease the deviation

offset value by one step using the up or down arrow key. This enables the RSS to strap
this channel coded if you just left the align channel screen which straps the radio clear.

(g) Key the radio, measure and record the Secure deviation. Label the result as DVP DEV.

(h) De-key the radio.

(i) The Secure deviation measured should be adjusted to be 4 KHz +/- 500.

(j) To calculate the Secure Deviation Offset adjustment required, apply the formula below to

the measured deviation:

Steps = LOG (DVP DEV / 4000) * 20 / .35

(k) Use the DOWN or UP arrow keys to decrease or increase the value shown on the

display for Secure deviation. Note that the number shown is in hexadecimal. The value
of this number ranges from F0 to 1F. As an example, if the starting value is F9, repeated
pressing of the UP arrow key would produce the following sequence - F9, FA, FB, FC,
FD, FE, FF, 00,01, 02, 03, 04, 05, etc..

(l)

Re-key the radio, and measure the deviation again. Repeat the adjustment, until
measured deviation is 4 KHz. Note that if the channel you're using has not been
properly aligned beforehand, it may not be possible to correctly align the Secure
Deviation Offset.

(m)

If the Secure Deviation Offset adjustment does not provide enough "steps" for you to
align, then the channel is not aligned properly, or the radio needs service.

(n)

Reprogram the radio.

Servicing the Radio