Motorola HT 1000 ユーザーズマニュアル

19

Each SERVICE screen provides the capability to increase or decrease 
the ‘softpot’ value with the keyboard UP/DOWN arrow keys 
respectively. A graphical scale is displayed indicating the minimum, 
maximum, and proposed value of the softpot, as shown in Figure 3.

Adjusting the softpot value sends information to the radio to increase 
(or decrease) a DC voltage in the corresponding circuit. For example, 
pressing the UP arrow key at the Reference Oscillator screen instructs 
the radio microprocessor to increases the voltage across a varactor in 
the reference oscillator to increase the frequency.

In ALL cases, the softpot value is just a relative number corresponding 
to a D/A (Digital-to-Analog) generated voltage in the radio. All 
standard measurement procedures and test equipment are similar to 
previous radios. 

Adjustment of the reference oscillator is critical for proper radio 
operation. Improper adjustment will not only result in poor operation, 
but also a misaligned radio that will interfere with other users 
operating on adjacent channels. For this reason, the reference 
oscillator should be checked every time the radio is serviced or once a 
year, whichever comes first. The frequency counter used for this 
procedure must have a stability of 0.1 ppm (or better).

1. From the SERVICE menu, press F2 to select TRANSMITTER 

alignment.

2. Press F2 again to select the REFERENCE OSCILLATOR softpot.

3. Press F6 to key the radio. The screen will indicate that the radio is 

transmitting.

4. Measure the transmit frequency on your service monitor.

5. Use the UP/DOWN arrow keys to adjust the reference oscillator per 

the targets shown in Table 13.

VHF

0 to 300 Hz

UHF

0 to 300 Hz

800/900 MHz

0 to 300 Hz