Dataradio Paragon, Техническое руководство

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120 20170-204a Paragon
PD
Technical Manual
51
- Zoom the RF Error window: select 10Khz range
2. Key the transmitter by pressing the front panel TX-Key button and measure the carrier output
frequency. It should be within ±300 Hz. If it is not, adjust the TCXO (IC700) to trim to meet the
requirement, preferably within 100Hz.
6.4.3.4 Low-Frequency Balance Adjustment
Note:
•
PGM800Win version 3.00 or later must be used for T881 adjustments and can also
be used to adjust T857 and T837 units. Electronic potentiometer (256 step) is used
to allow channel adjustment of two-point modulation (Low freq. balance).
•
PGM800Win version 3.00 or later must be used, if the unit serial number is longer
than 6 digits.
1. Apply the following settings to the IFR:
– Receiver mode and Oscilloscope display (Source Demod out connector, DC coupled).
– IFR RX frequency to match the radio transmit frequency
– IF Filter set to 30KHz
– Zoom the Deviation window: select 10kHz Range and DC coupling.
2. Select the active or, the lowest (in the case of multi-channel base) frequency channel (via dip
switch)
3. Transmit a square wave by pressing the BDLC
PD
’s PF1 button and following the procedure out-
lined in section 3.2.1.1.2.2. You can also run both programs on the same computer if two serial
COM ports are available.
4. Press EPOTs button. Adjust IC220 via PGM800Win “reference modulation” to obtain the best
square wave, no damping, no overshoot. (You can use either the mouse or up and down arrow
keys). Record the deviation read.
5. If transmission has not ended by itself, press BDLC
PD
PF1 to stop it. For single-channel unit,
proceed to step 8.
6. For multi-channel unit, select the highest frequency channel. Transmit a square wave by pressing
the BDLC
PD
’s PF1 button and following the procedure outlined in section3.2.1.1.2.2. Record de-
viation again.
7. The difference in deviation between the two channels should be less than ±300Hz. If not, re-
adjust IC220 to "average" the square wave shape on both channels until the spec is met.
8. To confirm the adjustment, select the active, or the lowest frequency channel. Compare the de-
viation produced between:
- 1000 Hz sine wave adjust tone and
- Random data
The difference should be lower than indicated in the following table. For multi-channel unit, re-
peat this step on the highest frequency channel.
Table 11- Low Frequency Balance – Deviation Readings (from TXON7 1000Hz and TXON4 random data)
Modulation VHF UHF 800/900 Series I 800/900 Series II
2FSK Half Channel 0.4kHz 0.4kHz 0.4kHz 0.4kHz
2FSK Full Channel 0.5kHz 0.5kHz 0.5kHz 0.5kHz
4FSK 1.7kHz 1.7kHz 1.7kHz 1.7kHz