The Transceiver

The painting off aluminium plate is not easy, as you can see the colour drops. We will see if I can fix this later?

I have now run a few QSO with this transceiver on SSB. And this was the goal. It is not perfect but it works. In Rx the sensitivity is high enough with preamp on. On Tx it is from 10-15W out on all bands. I hope to test on 6m but for the moment is veary  quiet on this band.

As you can see from the display a lot has ben implemented in SW, RealTimeClock, Battery indicator, temperature, one VFO, vfo step size, Rx Rf gain or Atten, S-meter, Band select, mod set,  tune, power set 1- 15W and settings include touch screen calibration.

POWER and SWR  indication is not yet implemented in SW, hopefully ok in HW. Cw-keyer and CW decode is not implemented, same test has been made. I have separate code tested. Mic Compressor is not tested yet more qso and test is needed.

SD card is working. But not used to much. Can be used for settings and calibration. Touch screen is working but a bit slow, I hope to speed up it in a newer sw code?

The AF Filter CW/SSB has some strange behaviour so it is bypassed for now a MAX7400, I tested it before I do the schematic, murphy has been her.

As they say use the TRANSCIVER Make QSO, I haw new things to build (Digital versions, sty tuned)

73 de SM4HNG

 

TRX Board

This is a board from Dian Kurniawan (YD1OSC). BritX All Band HF Exciter with Audio BPF and 1 Watt TX preamplifier.  It is a design based on BITEX from Ashar Farhan.

I have take away the tx amplifier, I use my own design on the FrontEnd 02 board. Also take away the rx amplifier before mixer, then it works in/out to RF mixer.

Next mod is for CW I won’t sidton on audio if keying, so 12VTX to audio amplifier LM386 is taken from 12V to make it possible

I will son describe how I put all this together to a transceiver 1,8 – 52 MHz.

 

The Key

This is a key from Russia I bought in a ham market in Vårgårda 2019. Now mounted on a bit of  oak wood. Perfect for field operation. 

QRP Digital Board 01

                               KiCad

The Cad of this take some time, first try to put in CPU on the board didn’t  succeed , so the final is with the CPU module from . Same small mistakes is now fixed, and all function is verified. The result is a board with a lot of function.  Extra Dac for AGC , 8 i/o and one UART, 4 ADC channels this is for future use.  Tested and working is AREF analog reference for CPU module, RTC + EEPROM, VFO + BFO (Si5351), LP-Filter (CW/SSB), Input for CW key, MIC amplifier, MIC compressor, SD-CARD, TFT and Touch display, temp sensor, encoder and ton-generator for CW. Connection for the earlier done board PA, LP-Filter, Frontend 02. 

Next is a modified TRX board stay tuned!