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.


*. 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


RTC02B to BitX Oscillator connection

Ada beberapa pertanyaan masuk ke e-mail saya menanyakan bagaimana koneksi RTC02B dengan BitX. Saat ini bisa di katakan Bitx adalah board ssb trx homebrew yang paling populer di Indonesia. Oleh sebab itu saya akan gambarkan koneksi oscillatornya sebagai berikut. Bila karena satu dan lain hal sinyal oscillator terlalu kuat silahkan di tambahkan attenuator.



Berikut contoh video BITX menggunakan RTC02B (tapi tidak menggunakan BFO nya)


RTC02B (English) user Manual

Radio Transceiver Controller
Si5351 on board


  • Si5351 clock generator with 25/27 MHz Xtal
  • HF All band controller
  • BFO oscillator out
  • USB/LSB/AM switch control pin
  • IF bandwith control pin
  • AGC Fast/Low control pin
  • NB control pin
  • VFO A/B
  • CB mode channel
  • Voltage monitor, Temperature monitor, Fordward and Reflected reading
  • Alarm indicator and alarm driver
  • 6 onboard button
  • 1 rotary plus + push button
  • Fout 4X freq operasi (SDR mode)



mode button

  1. BAND button

Band selection

  • 160m =             800 MHz           –              1.999 MHz
  • 80m =             500 MHz           –              3.999 MHz
  • 40m =             900 MHz           –              7.249 MHz
  • 30m =             100 MHz         –              10.149 MHz
  • 20m =             000 MHz         –              14.349 MHz
  • 15m =             000 MHz         –              21.449 MHz
  • 10m =             000 MHz         –              29.699 MHz
  • 26m =             400 MHz         –              11.499MHz
  • CB =             965 MHz         –              27.405 MHz
  • ALL =                 500KHz         –         32.000 MHz

Each band have their own ouput control pin with active logic high 5V to pre-drive BPF dan LPF. Special for 26m the control band follow 30m band and CB will follow 10m band.

 Selected active band will store into micronctroller EEPROM after a few second.


  1. VFO A/B button

VFO A/B button used to choose active VFO A or B, each band have A/B sto selected VFO and will be store in microcontroller EEPROM after a few second.


  1. MODE button

MODE Button used to choode modulation (LSB, USB, CW, AM and SDR). This button will drive output pin for selected modulation out pin and or drive BFO frequency out. This modulation pin out will have 5V high logic pin to drive external BFO for example.

SDR mode mean no IF offset and multiply by 4, such as for tayloe need 4 times LO.

See Frequency out pin for more detail formula

Active mode will be store in microcontroller pin after a few second


  1. SETTING button (activated alternate function button)

Setting button used to choose setting function combine with another button

Push SET button then push following button
*. BAND, use to set Bandwith (BW) setting, if Band with (wide/narrow) , This will affect BW pin high or low logic for bandwith control

*. MODE, use to set AGC F(fast) or S (slow), this with affect AGC pin logic high or low for AGC control

*. A/B, use to NB, Noise blanker , this will affect NB pin logic high or low for Noise blangker control

 Push SET button to go back to dial mode

  1. DOWN/UP button

  Button UP atau DOWN use to auto scan up and down on selected band


  1. Button rotary DIAL

Button rotary dial use to choose operation frequency by left (down) or right (up).


  1. Button rotary PUSH DIAL

If we push the button rotary dial this will change frequency step for each rotary step.


RTC02B Initialization

 Factory Reset
Push SET button when powering on module until setup menu appear it will reset all EEPROM setting into factory default.

EEPROM Value setting

For the first time we need to set up the system such us correction value (calibration), IF and etc.
We need to push DWN button on start up until initialization menu show up. Below are step by step initialization set up. Push DWN button on start up did not reset tofactorey default value.

  1. Correction menu will show up as default initialization.

Default correction value is zero except already calibrate. If we dont want to set the new calibration value, just push DWN button to skip then go to other setup.
Read the vfo value on VFO out pin. If counter read value did not show exact 10MHz please do rotate dial button left or right until counter read exact. Then push DWN button for next step.

  1. IF SSB

IF SSB use to set up IF offset value, we need to rotate dial rotary button lef or right. We could push rotary dial button also to change step.
Then push DWN button for next step.

  1. IF CW

Same as above but for CW mode
Then push DWN button for next step.

  1. IF AM

Same as above but for AM mode.
Then push DWN button for next step.

  1. BFO USB

BFO offset for USB. Default value is 1500Hz (1.5KHz), we could rotate rotary dial button to change the value.
Then push DWN button for next step.

  1. BFO LSB

BFO offset for LSB. Default value is -1500Hz (-1.5KHz), we could rotate rotary dial button to change the value.
Then push DWN button for next step.

  1. BFO CW

BFO offset for CW. Default value is 600Hz, we could rotate rotary dial button to change the value.
Then push DWN button to exit Initialization step.. then restart (power on – of


RTC02B Connetion and pinout

  • 12V supply pin (beware coneccting this pin)


  • Output pin

This pin have digital logic high (5V) when active and logic low (0V) when not active

  • Alarm pin (K2.0)
  • Band control pin (K2.1 – K2.3)(10m, 15m, 20m)
  • Band control pin (K3.0-K3.3)(30, 40m, 80m, 160m)
  • Mode control pin (K9.0-K9.3)(AM, CW, USB, LSB)


  • Frequency out pin
    • OUT FREQ (VFO out)

VFO out = IF + Display Frequency + SSB BFO offset

  • OUT IF (BFO out)

BFO out = IF – SSB BFO Offset

  • RX/TX input pin

This digital input in will accept 5v as RX state and 0V as TX state.
RX state wil drive LCD display to show RX state and set up VFO value according to rx state, special for AM mode, will offset RX vfo to AM IF. This wil also drive microcontroller to read s-meter value (see ADC input s-meter).

TX state will drive LCD display to show TX state and set up VFO value according to tx state, special for AM mode will not offset TX vfo to AM IF. This will alos drive microcontroller to read fordward (FWD) and reflected (REF) value (see ADC input pin REF/FWD)

  • ADC input pin

This input pin accept 0-2.56 DC volt input. Please be aware to to exceed the value. It will damage the Microcontroller.

  • Temperature input (0-2.56V)

Connect this pin into LM35 sensor temperatur (sold separately). Then glue it into Power Amplifer heatsink to read heatsink temperature.

LM35  Precision Centigrade Temperature Sensors



  • Vbatt (0-2.56V)

Connect this pin trought 10K trimpot/potensiometer to read supply voltage then do calibration with other voltmeter


  • REF (0-2.56V)

Connect this pin into SWR pickup reflected out then do calibration.

 pick up 1


  • FWD (0-2.56V)

Same as above but for fordward out.

 pick up 2

This is “KitsandParts” SWR pickup

  • S-Meter (0-2.56V)

Connect this pin so s-meter buffer then do calibration. (replace analog meter then connect it to microcontroller s-meter input) see example below


connection 01

7 watt Homebrew VHF Transceiver “miniRig BR07V”

Front 01E copy.jpg

Specification :

*. 7Watt Max TX power
*. Freq range 134-174 MHz
*. Support Repeater +600, -600, Split A/B
*. A/B VFO
*. Load and Save 40 record memory
*. Heatsink Temperature reading
*. Supply voltage monitor
*. 2.2 Inch TFT color display
*. Red theme

*. BR07V Unit
*. Microphone
*. DC Cable
*. Manual

BR07V is a handmade (homebrew) transceiver with 100% firmware develop by homebrewpartner / BuildRadio.

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For international buyer payment made through paypal, my paypal account is “dian@jalapindai.com”

for further information please contact or mail me :