Tuning!Of!The!Power!Amplifier - OM POWER OM2000+ User Manual

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5.4. Tuning'of'the'Power'Amplifier'
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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
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The)operation)of)a)mistuned)PA)will)cause)malfunctions,)the)increase)of)grid)current)and)problems)
with)TVI/BCI.))
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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.
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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.!
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Band!(MHz)! Tune!
1.845!
3.630!
7.050!
10.125!
14.175!
18.150!
21.230!
24.940!
28.450!
50.200!
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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.!
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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!a!TUNE!and!Is)graph!(>!l!<).!!
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CAUTION
CAUTION
Load!
70! 45!
69! 51!
50! 90!
72! 28!
69! 40!
81! 48!
47! 67!
61! 64!
33! 76!
22! 90!
Exhibit!6!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!Page!24!!from!35!
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Input!PWR!(W)!
75!
72!
71!
72!
70!
69!
65!
59!
52!
64!
NOTE!
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Output!PWR!(W)!
1500!
1500!
1500!
1500!
1500!
1500!
1500!
1500!
1500!
1500!