Table 15 Transmit Power Setting

 

VHF

 

 

UHF

 

 

 

 

 

 

 

 

Power Level

Test Frequencies

Power Level

Test Frequencies

 

 

 

 

 

 

 

 

136 - 174MHz

177.975MHz

 

450 - 512MHz

 

512 - 520MHz

 

 

 

 

 

 

 

5 W

5.2 - 5.4

4.2 - 4.4

4 W

4.2 - 4.4

 

3.2 - 3.4

 

 

 

 

 

 

 

1 W

1.2 - 1.4

1.2 - 1.4

1 W

1.2 - 1.4

 

1.2 - 1.4

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

800 MHz

 

 

900 MHz

 

 

 

 

 

 

 

 

Power Level

All Test Frequencies

Power Level

All Test Frequencies

 

 

 

 

 

3 W

3.2 - 3.4

2.4 W (Typ.)

 

2.4 - 2.6

 

 

 

2.9 W (Max.)

 

 

 

 

 

 

 

 

 

 

Transmit Deviation Balance (Compensation)

Compensation alignment balances the modulation sensitivity of the VCO and reference modulation (synthesizer low frequency port) lines. The compensation algorithm is critical to the operation of signalling schemes that have very low frequency components (e.g. DPL) and could result in distorted waveforms if improperly adjusted.

NOTE: Disable all audio band filters on the service monitor.

NOTE: (Secure-Equipped Radios Only)

If a secure module is currently installed in the radio being aligned, refer to the appendix at the rear of this manual. Read section III, “Secure Alignment Procedure”, before performing the transmit deviation balance (compensation) procedure.

1.Press F4 to select the TRANSMIT DEVIATION BALANCE softpot. The screen will indicate the transmit test frequencies to be used.

2.Begin with the lowest test frequency shown on the screen.

3.Set the Test Box (RTX4005B) meter selector switch to the “MX DISC” position, and inject an 80Hz tone at 100mVrms into the AC/DC MTR port. Keep the ac voltmeter in parallel to ensure the proper input signal level.

4.Press F6 to key the radio, and measure deviation. Record this measurement.

5.Change the input tone to 3 kHz, 100mVrms and use the UP/ DOWN arrow keys to adjust the deviation to within ±2% of the value recorded in step 4.

6.Change the input tone back to 80 Hz and measure the deviation.

7.Repeat steps 5 and 6 until the 3kHz tone deviation is within ±2% of the 80Hz tone deviation.

8.Press F6 to dekey the radio, and press F8 to program the softpot value. Press ENTER to move to next softpot value.

22

Page 44
Image 44
Motorola HT 1000 service manual Transmit Power Setting, Vhf Uhf