FY 6800 Generator as Beacon

 

Introduction

The FY6800 generator is a good product. Why?

HF full band, schematics, open source code and lot of inputs/outputs to control it.

Just connect an Arduino on TX/RX and Trig/Vco inputs to create BPSK , RTTY, Hellschreiber, CW, WSPR beacon.

FY6800 beacon features:

• LF, HF full band.
• Power : 19dbm on 40 meters.
• Modes : BPSK , RTTY, Hellschreiber, CW, WSPR.
• Trigger input for FSK modulation.
• VCO input for FM modulation.
• Arduino UNO
• LCD 4×20 display.
• RTC (for WSPR)
• Breadboard wiring.

The concept:

The challenge is to use FY 6800 function generator to get BPSK , RTTY, Hellschreiber, CW, WSPR on ch1 output.

As you can see on fy6800 rear, there are TTL serial bus on HE8 connector. Connect it to an Arduino and it is possible to generate different HAM modulations.

Special functions port

Trigger TTL input is used for FSK, PSK modulation (RTTY, BPSK31,CW and Hellschreiber)

VCO input is used for FM modulation (RSID and WSPR)

Don’t forget low pass filter between generator and antenna.

---

Schematics

I use a Breadboard to test  differents HAM modulations

---

Inside FY6800

You will be find all schematics and the serial protocol here :

https://github.com/f4goh/FY6600-15-30-50-60M

Programming Software

https://github.com/f4goh/FY6800Beacon

Compiling the program from the Arduino environment is easy

Indeed, it is necessary to install the libraries for the RTC and the LCD.

 

You will find an example here:

https://github.com/f4goh/FY6800Beacon/blob/master/examples/FY6800_Modulation/FY6800_Modulation.ino

Select between this 3 modes in loop function

//bridge();                  // to send command manually with any serial terminal

//test();                      // to test each modulation send 1,2,3,4,5 on any serial terminal

syncTime();              // to send wspr each even minutes

Serial command brief

WMF07041500000000  : frequency on main channel CH1 7.041.500 HZ

WMN1 : CH1 on , used as PTT

WPF0 : PSK modulation

WPM3 : external dc trigger

WFK07041670000000 : main frequency and 170 hz shift

WMN0 : CH1 off

Each command must finished by LF 0xa character. FY6800 return an LF to acknowledge.

It is possible to use PC software and spy data on a serial terminal to understand how different commands works.

---

HAM modulations configuration

Trigger TTL input is used for FSK, PSK modulation (RTTY, BPSK31,CW and Hellschreiber)

---

Rtty (FSK)

WMF07041500000000

WMN1

WPF0

WPM3

WFK07041670000000

WMN0

---

Hellschreiber (same as CW)

WMF07041500000000

WMN1

WPF0

WPM3

WFK00000000000000

WMN0

---

PSK

WMF07041500000000

WMN1

WPF2

WPM3

WMN0

---

WSPR (FM)

WMF07040000000000

WMN1

WPF5   fm

WPM1 vco

WFM00000005000000  modulation range 5Hz

VCO input is used for FM modulation (RSID and WSPR)

Arduino PWM generate analog control for VCO. So a low pass filter is added to have continous voltage.

4 voltages levels for WSPR modulation

Set amplitude voltage as you want. I measure 19dbm at 7Mhz. (AMPL : 5V)

To test WSPR i must set AMPL to 40mV to not saturate my receiver next to generator.

WSPR test on CH1 output at 19dbm (AMPL : 5V)

---

Conclusion

It will be possible to assemble and program it in less than 30 minutes on a breadboard. The cost of the equipment being very low, you take no risk of trying and the FY6800 can be used for other things.

This project is usefull for understand HAM modulation without using ad9850 DDS.

If you improved source code, please send me your upgrade by email. I add it on github.

73 Anthony F4GOH

---