July 16, 2004 6881094C28-D
6-6 Radio Alignment Procedures: Transmit Power Alignment
6.6 Transmit Power Alignment
This alignment procedure adjusts the transmit power of the radio and must be performed for three
different power levels (Low, Mid, and High), at multiple frequencies for each power level, to allow for
proper alignment across the entire RF band. The RF band is divided into frequency zones with a
calibration point (value) in each zone.
NOTES:
• The same softpot attenuation value will result in different radio output power levels at different
frequencies.
• All power measurements are to be made at the antenna port.
• Transmit Power alignment is required after replacing (or servicing) the transceiver board.
• For 700/800 MHz radios only
: FCC requires that portable radios transmitting below 806 MHz
transmit at less than 3 watts. Therefore, 700 MHz frequencies are tuned at mid-power levels by
the factory.
To align transmit power:
1. Select the TX Power (Low, Mid, or High) alignment screen. The screen will indicate the
transmit frequencies to be used. See Figure 6-6 on page 6-7.
2. Left-click the desired frequency field (starting with the highest frequency shown).
3. Left-click the PTT Toggle button on the screen to make the radio transmit. The screen
indicates whether the radio is transmitting.
4. Measure the transmit power of the radio with a service monitor.
5. Adjust the softpot value until the required power, as shown in Table 6-2, is indicated on the
service monitor.
6. Repeat Steps 2 through 5 for all frequencies and all power levels.
7. Left-click the Program All button on the screen to dekey the radio and save the tuned values.
8. Left-click the Close button on the screen to return to the Transmitter Alignments menu.
Table 6-2. Transmit Power Settings
Power Level
Transmit Power (Watts)
VHF UHF R1 UHF R2 700 MHz 800 MHz
Low 1.2–1.4 1.2–1.4 1.2–1.4 1.2–1.4 1.2–1.4
Mid ———2.5–2.7—
High 6.2–6.4 5.2–5.4 5.0–5.3 — 3.2–3.4
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