SSB modulation and demodulation module for stand alone SDR or direct conversion trx

Specification :
*. STM32F103C8, 32bit, run on 72 MHz clock
*. 19.200 Hz ( 8 x 2400Hz ssb bw ) audio sampling for I and Q output from Tayloe rf mixer
*. 27 taps Low Pass Filter (FIR)
*. PT8211 LSBJ DAC for I/Q transmit audio
*. 8Bit R2R DAC for speaker out
*. Software AGC calculation

flow code demodulation process
1. Get ADC value from amplifier of I and Q mixer output with 19.200 Hz sampling rate, trigger by timer interrupt
2. Filter the ADC value using LPF FIR calculation, store sample to FIR Buffer for the next process
3. Do sin and cos calculation for I and Q input (90′ phase difference)
3. Perform AGC calculation for speaker output level
4. Send Final Value to DAC

flow code modulation process
1. Get ADC value from microphone with 19.200 Hz sampling rate, trigger by timer interrupt
2. Perform Compressor calculation for transmit modulation level
3. Filter the ADC value using LPF FIR calculation, store sample to FIR Buffer for the next process
3. Do sin and cos calculation for I and Q output (90′ phase difference)
4. Send Final Value to TX DAC (PT8211)

STM32F103C8 didn’t have any DSP multiplication feature, so we used sin and cos constant value in the constant array, we just need 8 sin and 8 cosine value for doing this. This configuration will save around 900 clock cycles. All the process must be done in 0.000052083  seconds before the next interrupt timer trigger next repeat proses.

Dian Kurniawan

 

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SSB CB Reborn

Setelah sebelumnya meluncurkan HBR1HF, juga mempertimbangkan masukan dari rekan-rekan pengguna radio di Indonesia serta keinginan mengingat mengenang kembali era 80an Hambuilder berencana meluncurkan produk CB Transceiver. Saat ini “HBRCB” sedang dalam tahap protoype akhir. Pilihan desain jatuh pada penggunakan SA/NE602 sebagai mixer dan demodulator, lalu ladder xtal fillter sebagai SSB konverter nya. Ya product ini hanya mensupport SSB mode pada CB. Selain karena alasan harga juga kesederhanaan serta metode xtall filter menjadi alasan utama.

Hasil uji prototype HBRCB di lab Hambuilder menunjukkan hasil yang menggembirakan. Sensitivitas yang sebanding dengan BitX dan noise level yang cukup rendah cukup menjanjikan.

Spesifikasi :
*. mixer SA602/NE602
*. modulator SA602/NE602
*. Frequency synthesizer Si5351 (VFO/BFO)
*. ATMega16 Controller
*. IF 11.059200 MHz
*. SSB Modulation
*. 7segment Display
*. LED S-meter
*. Power 25Watt at 13.8V
*. RJ-45 Microphone connector
*. Dimesions 126mm (w) , 40mm (h), 132mm (d)
*. Aluminum enclosure

 

Hambuilder Team

HBR4HF – Hambuilder 4 Band HF Transceiver

HBR4HF specification

  • Heterodyne 10MHz Xtal filter exciter based on Hambuilder BritX exciter
  • 300-25000Hz audio band pass active filter using NE5532
  • 4 Band coverage (80m, 40m, 30m, 20m) with 3 selector LPF BPF
  • 20-35 watt RF power output,
  • 2x IRF 530 Final RF amplifier
  • SSB modulation
  • 16×2 char LCD
  • Si5351 VFO and BFO synthezyzer based on RTC01C controller

 

 

 

Regards

 

QRP HBR-HF10 Prototype (receiver test)

Specification:

  • BritX exciter, based on BITX exciter with on board 2 to 30 Mhz fixed inductor BPF using FST3253 band switch
  • Small form factor (common component are smd)
  • RTC02B controller (2.2 TFT display) with special firmware
  • ABS enclosure with acrylic panel

This exciter will be power up with 10watt linear amplifier. using RD16HHF1, and RD00HHF1 as driver and  4 Band LPF

In the future there will be an additional daughter board to improve bitx performance like:

  • 3-5 Watt audio amplifer with AGC
  • DSP audio processing for speaker
  • DSP audio processing for microphone and also audio compressor

This exciter availabe now in Indonesia, please visit to buy it..
https://www.tokopedia.com/jalapindai-store/britx-hf-exciter-board

’73

BRHF10 = BRitX + RTC02B

RTC02B external VFO

Another version of RTC02B as an external vfo. It is come with an abs plastic enclosure, 2 bnc rf out and dc jack connector.

This version was build to meet old channelled transceiver local oscillator replacement. So they do n ot have to open or do alot modification of their vintage transceiver.

Hambuilder HF transceiver prototype

Desain ekonomis Homebrewpartner/Jalapindai HF transceiver enclosure. Pada series ini tema yang di gunakan adalah “Hambuilder” untuk semakin menguatkan kesan homebrew/diy nya.

specification:

*. RTC02B as main controller (special firmware)

*. Single conversion heterodyne (smd Bitx variance)

*. 4 onboard BPF (2-4, 4-8, 8-15, 15-30 MHz) fixed inductor BPF

*. FST3253 bandswitch selector

*. 10watt linear Amplifier

DDS CB AD9850

DDS ini masih sama dengan DDS compact tetapi didesain dengan firmware khusus untuk 200CB channel juga di 11Mc. Diharapakan dengan DDS ini akan kembali menyemarakan penggunaan CB di Indonesia

spesifikasi

  • DDS AD9850
  • Microcontroller ATMega8
  • 16×2 charackter LCD
  • 200 channel 27MHz CB
  • 11.400 MHz – 11.500 MHz (11MC band)
  • Rotary Encoder
  • Autosave and restore lattest dial frekwensi
CB DDS

CB DDS

Harga kit : Rp. 200.000,-

note: saat ini Kit DDS CB Sold out, dalam waktu dekat dapat diperoleh di homebrewpartner.com