Bazen pile-up olur çok istersin QSO yu ama bağır bağır yırtın duyuramazsın italyanların 1000-1500W çıkışlrından yada rusların 400W üzeri çıkışlarından malesef.
10 yıl önce Bulgarların
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OM4000A SSB 4000W TRT radyo istasyonu mubarek işte resimlerle o oyuncak
Elmi yaman beymi yaman misali "Tıs" desen duyar herhalde (Okkalı Anten şart) 
GENERAL DESCRIPTION AND THE ADVANTAGES OF THE OM4000A AMPLIFIER
The OM Power model OM4000A is an automatic power amplifier, designed for use on all short wave amateur bands from 1.8 to 29.7 MHz (including WARC bands) and all modes. It is equipped with a two pieces of ceramic tetrode FU728F.
THE ADVANTAGES OF OM4000A
Full compatibility with:
- ICOM
- ELECRAFT
- KENWOOD
- TEN-TEC ORION
- YAESU
- Icom transceive protocol using by MicroHAM devices ( CI-V output )
Automatic switching between bands
Automatic tuning within the band according to segments
Automatic switching of band pass filter
Automatic switching of antenna switches
The possibility to use 2 different antennas within one band or segment
Specification of OM4000A:
Frequency coverage: Amateur Bands 1.8 – 29.7 MHz including WARC
Power output: 4000W in SSB and CW,
3000W in RTTY, AM and FM
Input Power: Usually 60 to 90W for full Output Power
Input Impedance: 50 Ohm, VSWR < 1.5 : 1
Power Gain: 17 dB
Output Impedance: 50 Ohm unbalanced
Maximum Output SWR: 2:1
SWR protection: Automatic switching to STBY, when reflected power is 350W or higher
Intermodulation distortion: 32dB below nominal output
Suppression of harmonics: < -50 dBc
Tubes: 2x FU728F Ceramic tetrode
Cooler: Centrifugal blower + Axial blower
Power supply: 2 x 230V – 50 Hz one or two phases
Transformers: 2 pcs of toroidal transformer 3kVA
Dimensions: 485 x 200 x 455mm (width x height x depth)
Weight: 46 kg
Protection circuits: - VSWR too high
- Input power too high
- Output power too high
- Plate voltage too low
- Anode current too high
- Screen current too high
- Grid current too high
- Mistuning of PA
- Hot switching protection
- Soft start for protecting your fuses
- “switch-on blocking “ at opened amplifier
LED indicators: - Current at control grid (Ig1) - 2 LEDs
- WAIT – preheating of tube (150 sec.)
- STBY - standby
- OPR – operation mode
- FAULT – failure, switching off for abt. 2 sec.
- INHIBIT – operating condition
- ANT 1 - which ANT is in use
- ANT 2 – which ANT is in use
- ANT - ANT selection
Bar graph indications: - Power output – 50 LEDs
- Reflected power – 20 LEDs
- Ig2 current - 10 LEDs
- Anode voltage, anode current, tuning – 30 LEDs
