CALAMP WIRELESS NETWORKS INC. BDD4T881 Manual Do Utilizador

120 20170-200

Paragon

Technical Manual

WARNING: Do not attempt to re-tune the IF stages (i.e. L312 to L318).

These adjustments do not need to be re-adjusted after frequency re-programming.
Touching these coils will have a direct impact on the DSP modem coefficient settings
and may significantly reduce the radio performances over data.

6.2.2.4

SINAD and Linearity Check

1. Apply the following settings to the IFR:

Generator mode, Output T/R

IFR TX frequency to match the main radio RX frequency

Filter set to wide band (no audio filter)

Select Gen2 (Modulating tone fixed to 1KHz). All other Gen must be off, except for “wide-
band”.

Set deviation to

3.0KHz for full channel or

1.5KHz for half channel radios.

2. Lower the RF level to get a 12dB SINAD reading. Level must be better than -110dBm (including

cable loss).

3. Offset the IFR TX frequency 2KHz (full channel) or 1kHz (half channel) above the main radio RX

frequency, record the SINAD reading. It should remain within 1.5dB from the on frequency
SINAD reading.

4. Offset the IFR TX frequency 2KHz (full channel) or 1kHz (half channel) below the main radio RX

frequency, record the SINAD reading. It should remain within 1.5dB from the on-frequency
SINAD reading.

Note:

If one of the above requirements is not met, try to re-tune the front-end. If it is still “failed”,
contact your Dataradio technical support.

6.2.2.5 RSSI

Adjustment

Note: This check is only recommended for Paragon

model running DBA protocol 3.06.009 series or

later.

1. Apply an on-channel signal from the RF generator at a level of -110dBm with deviation of ±3kHz

(full channel) or ±1.5kHz (half channel) at 1kHz tone.

2. Adjust RV301 (RSSI level) to give 2.0V RSSI output when measured with a multimeter at SK301

pin 2 or on the relevant backplane board at SK1 pin 5 (see Figure 30 for test point location).

3. Vary the RF level in 10dB steps and check that the RSSI output voltage changes at a rate of a

10dB/V (±0.20VDC) over the range of –120dBm to –80dBm. If the requirement cannot be
reached, contact your Dataradio technical support.