OM POWER OM2000+ Tuning Procedure And Part List page 2

1.2. Tuning of the Power Amplifier
The OM2000+ power amplifier is operated in class AB. Thus it's possible to obtain a maximum output
power at excellent linearity. For this purpose the amplifier has to be tuned carefully
The operation of a mistuned PA will cause malfunctions, the increase of grid current and problems
with TVI/BCI.
If the input power is higher than 10W and the power amplifier is NOT correctly tuned, the safety
devices will switch it to STBY. After switching the amplifier to STBY, you need to switch it back to
the OPER mode by pressing RESET button shortly.
A tuning table is delivered with the power amplifier. For coarse tuning select a band with BAND switch
and choose the setting of "TUNE" and "LOAD" capacitors according to the table.
Band (MHz)
1.845
3.630
7.050
10.125
14.175
18.150
21.230
24.940
28.450
50.200
Delivered tuning table was made for 50 Ohm loading of PA (dummy load). Each amplifier should have
different values depending on used frequency and used type of antenna. Make your own table valid
for your real conditions.
There are two ways how to do fine tuning. The first method uses a gradual increase in the input power
when tuning the PA (as most operators accustomed). In every case we recommend adjust the display
for both of methods so it shows two parameters important for fine tuning - TUNE and Is graph (> l <).
CAUTION
CAUTION
Tune Load
70 45
69 51
50 90
72 28
69 40
81 48
47 67
61 64
33 76
22 90
NOTE
Exhibit 11
.
Input PWR (W) Output PWR (W)
75
72
71
72
70
69
65
59
52
64
1500
1500
1500
1500
1500
1500
1500
1500
1500
1500
Page 2 of 12