Controller for the linear power amplifier -

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Controller for the linear power amplifier, version 4.0, RF detector

Controller designed for Amateur Radio LDMOS Amplifiers built at home.  Based on powerful firmware on board Arduino Nano, it shows precise  measurements, delivery voltage sequences,
all protections for LDMOS  devices, touch screen switch controls and functions. It also  incorporates the Rf Band Decoder that selects the Low Pass Filter  automatically without additional cables.
Dimension: 148mm*120mm*20mm

Technical data
RF Band decoder 1.8 - 54 MHz
Fan Speed Controller Auto/Manual (No PWM)
Nextion dysplay controller
SWR, Power output, drain voltage, drain current, Temperature. METERS
Fulree FJ60D12C3 Step down 53v - 12v
Continuous Carrier >xxx-Watt protection
BTS 50085 50-60V 40A Solid-State Swith
Sound Alarm 800 Hz
Antenna Relay/Bias sequencer (20 Ms)
Antenna Switch/LPF relay drivers (80 mA)
DS18B Temperature Sensor Controller with protection
Protection of incorrect band selection
RF Band Decoder
Is one of the most attractive options . No more incidents by forgetting  or not changing the band selector.
You do not need to find the specific  radio interface for amplifier tracking. Video

Circuit for Arduino Nano integrated in the controller

Protections for LDMOS devices
High temperature, High current, High voltage, High output power.
High SWR.  LDMOS devices are usually very robust and support SWR 65:1 such as  BLF188XR / MRF1K50H. But this is not enough to extend the life of the  linear amplifier for Ham Radio since some components can overheat and  break. Or worse, we forget to select or connect the antenna. The video  shows the precise protection when SWR>2  Video
Continuous carrier detector. Some  amplifier designs can withstand long cycles with an output of 1300  watts in SSB. But a continuous carrier requires twice the effort.  Additional heat sink, huge ferrite cores and duplicate components, this  increases the cost of home manufacturing. The video shows a protection  for continuous carrier >8 seconds >700 watts.  Video
Wrong Band Selection. Operating  an amplifier in attenuation frequency can be fatal. The video shows the  protection when the 80 meter filter is selected manually while the  radio is operating at 40 meters. In addition, protection is also  activated if the Low Pass Filter is damaged. This function does not need  a SWR meter at the filter inlet.  Video
All protections were tested and guaranteed with genuine components, never tested with fake components.
The nominal voltage of the controller is 53v and does  not need a separate 12v source. The controller incorporates a Step Down  60v-12v DC Fulree FJ60D12C3 3 Amp device:

IDC connections
All are compatible with current KM3KM designs, board connections

Voltage sequence
The voltage sequence  prevents the relays from burning with an RF arc. Due to the mechanical  movement of the relays(GRL2)  the delay is 10 milliseconds when the PTT  is down, then 12 V Bias and  drain voltage is delivered 20 milliseconds  after PTT, total time 20 milliseconds (On Air) in Manual Mode. The  8-bit PIC micro controller detects the frequency and connects the LPF  relays, after 15 milliseconds it connects the 12 V Bias and  drain  voltage, total time 25 milliseconds (On Air) in Automatic Mode. I measured the delays wit an oscilloscope, but this effect can be  seen with a high speed camera. The led indicates the voltage delivery  after  relay sound. Video
Note  that in SSB mode the radio will not emit RF without modulation, 200  milliwatts are required to detect the operating band. Most radios  inpulse RF with PTT click, this is enough.
Manual Band Select time sequence:

Auto Band Select time sequence:

The price of the controller is $199, you can buy it here
The price of the controller PCB is $40, you can buy it here

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