Tuning O F T He P Ower A Mplifier - OM POWER OM2000+ Manual

5.4. Tuning o f t he P ower A mplifier
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 o peration o f a m istuned P A w ill c ause m alfunctions, t he i ncrease o f g rid c urrent a nd p roblems
with T VI/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 a nd c hoose t he s etting o f " TUNE" a nd " LOAD" c apacitors a ccording t o t he t able.
Band ( MHz) Tune
1.845
3.630
7.050
10.125
14.175
18.150
21.230
24.940
28.450
50.200
Delivered t uning t able w as m ade f or 5 0 O hm l oading o f P A ( dummy l oad). E ach a mplifier s hould h ave
different v alues d epending o n u sed f requency a nd u sed t ype o f a ntenna. M ake y our o wn t able v alid
for y our r eal c onditions.
There are two ways how to do fine tuning. The first method uses a gradual increase in the input
power w hen t uning t he P A ( as m ost o perators a ccustomed). I n e very c ase w e r ecommend a djust t he
display for both of methods so it shows two parameters important for fine tuning -­‐ TUNE and Is
graph ( > l < ).
CAUTION
CAUTION
Load
70 45
69 51
50 90
72 28
69 40
81 48
47 67
61 64
33 76
22 90
NOTE
Input P WR ( W) Output P WR ( W)
52
53
55
54
54
62
50
51
43
52
.
2000
2000
2000
2000
2000
2000
2000
2000
2000
1500
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