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YO5PBG Wavelenght

Amateur Radio, QRP, Home Made

just the sketch, more later:


int clk = 9;
int data = 8;
int ena = 7;
int led = 13;
void setup() {
// initialize the digital pin as an output.
pinMode(clk, OUTPUT);
pinMode(data, OUTPUT);
pinMode(ena, OUTPUT);
pinMode(led, OUTPUT);
digitalWrite(clk, LOW);
digitalWrite(data, LOW);
digitalWrite(ena, LOW);
void loop() {
digitalWrite(led, HIGH);
// Load /R counter with a value of ####, MSB first  //14400 –> 1khz, 2880 –> 5khz, 14.4MHz XO
zero();       // 8192
zero();       // 4096
one();         // 2048
zero();         // 1024
one();          // 512
one();        // 256
zero();         // 128
one();         // 64
zero();         // 32
zero();          // 16
zero();         // 8
zero();         // 4
zero();       // 2
zero();       // 1
one();         // CONTROL, R = 1

enabl();       // ENABLE

// Load /N counter with a value of 621, MSB first
one();         // 512
zero();        // 256
zero();        // 128
one();           // 64
one();        // 32
zero();         // 16
one();        // 8
one();          // 4
zero();        // 2
one();           // 1
// Load /A counter with a value of max. 39 for :40 prescaler, MSB first
zero();       // 64
one();      // 32
zero();      // 16
zero();       // 8
zero();         // 4
zero();        // 2
zero();        // 1
zero();        // CONTROL, N & A = 0

enabl();      // ENABLE
digitalWrite(led, LOW);
digitalWrite(led, HIGH);


// zero:
void zero(){
digitalWrite(data, LOW);     // Load 0 on data
digitalWrite(clk,HIGH);    // bring clock HIGH
digitalWrite(clk,LOW);     // Then back low

// one:
void one(){
digitalWrite(data, HIGH);    // Load 1 on DATA
//      delay(100);
digitalWrite(clk,HIGH);    // Bring pin CLOCK high
//    delay(100);
digitalWrite(clk,LOW);    // Then back low

void enabl(){
digitalWrite(ena, HIGH);   // Bring ENABLE high
//    delay(100);
digitalWrite(ena, LOW);    // Then back low


I’m trying to make a data transmission link for my home automation system that I can receive in my city and nearby.
– For the moment tests are made with Arduino (UNO, MEGA2560 or MiniPro – Atmega328 @ 16MHz clock) and VirtualWire Library.
My first test & impresions:
– initial testing made with cheap 433MHz ASK/OOK Receiver (1 amp. stage + super regenerative stage + LM358 AF amp & data slicer) + the simple SAW oscillator type transmitter (both cost less than 3 euro) – all was ok @ 2000bps, tested only from one end to the other of the room!
– After the first step, considering that software and digital hardware side are ok, i wanted to see if this is possible also at a lower frequency… I have choosed 10,7Mhz: I made a simple crystal oscillator on-off keyed by the microcontroller by applying the data voltage to the bias resistor of the osc. transistor. As receiver I already had a MC3357 IF homebrewed years ago, so good i haven’t already moved it to the trash. But, hey, thats a NBFM receiver, while teoretically i need some kind of an AM receiver. Some success was achieved , but for limited distance and a lot of adjustments on the FM dicriminator coil and on the component values that make the conection from the FM IC to the the dataslicer. Basically i was trying to obtain the logic levels only by using the “silence” that makes an unmodulated transmitter when received by a FM receiver. Not good! I supose that much better operation will be obtained by audio modulating the frequency of the transmitter.

I’ve tried also with an TA7358 based direct conversion receiver and dataslicer, but with limited performance. I think i know what I should do now. Right now i’m restarting the ideea of using a crystal-stable , very simple RX and unmodulated transmitter because i believe this should really work with a better RX design especially in the AF+slicer area. I will also put an active filter.

Until now, AM Receiver seems to be best: if received signal is powerfull, i can decode 100BPS data imediatelly after the AM diode detector, filtered with 10k+100nF to ground. With dataslicer i get results even with almost unaudible signals, but i have to readjust the level to the slicer for almost any new level received. Maybe a comparator that compares noise vs signal and adjusts better the AGC should be a good idea.

One more thing: while doing tests, especially with the AM RX (an old 27MHz CB transceiver that i found in my shack), noise was very high if using Arduino Mega2560…? A lot of noise from the external display that i use with my laptop….

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Sebi – YO5OQF was kind to give me two ATMEGA644-20PU after telling him that i would like to program via Arduino a larger DIP style microcontroller, with more IO pins to use it in a more complex transceiver.

Unfortunately, i spend about three days without luck in burning the Arduino bootloader. I read a lot about Sanguino, Optiboot. I even tried several tens of times without luck to do something. But I’ve learned things. Like for example that “Sanguino” or ATMEGA644P support is not by default visible in Arduino after putting the Optiboot in the /hardware folder (you have to uncomment  the “Sanguino” lines in the boards list because it’s not officially supported).

I’ve tried burning the bootloader using Arduino 1.0.5 and the Arduino Mega2560 hardware (i had no available Uno for the moment). I’ve got errors like “unrecognized signature Ox….”. Arduino was no recognising my chip signature, and i’ve discovered that the signature was looking for was the one for the MEGA644P (P suffix!).

I tried a lot of stupid things, until I have downloaded an older Arduino version (0023). Than I’ve found these: It is where I’ve found my luck!

The developer has been short🙂 — “Arduino IDE support for the ATmega644 controller family. Based on Sanguino, but up to date. Promise. ” Even if up to date, was some years ago.

I tried to burn his code with Arduino 0023 version without luck (error: “cannot find ….. file), maybe because only UNO is working as ArduinoISP with this software version… Or maybe because… see below…

Than, i had a strange, working! ideea. Let’s put the atmega644 folder from the above mentioned site into the /hardware folder of the Arduino 1.0.5 software.

Ok, the Atmega644 appeared in the  menu, in Board list. Perfect. The same error while trying to burn the loader: “cannot find …./hardware/…atmega644p file” or something similar.

Than I’ve tot that this file should be one of the HEX files into the specified folder. What I did for my MCU type (the non-P version), I’ve changed the …atmega644\bootloaders\atmega644p\ATmegaBOOT_644.hex file name. ATmegaBOOT_644.hex to atmega644p. With no suffix.

And it worked.

Unfortunately, maybe because of the actual state of the Arduino 1.0.5 i wasn’t able to also compile/upload sketches to the ATMEGA644. But i was able to do it with the 0023 version.

For now, the Blink test sketch is working🙂. When programming the mega644 with the USB/serial adapter, push for a short moment the reset pin (9) to ground after starting the upload. Uploading is done on RXD0 and TXD0 pins — 14 and 15. Crystal: 16MHz.

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Hello friends. Almost 2 years since my last post here. I was busy with drinking beers, University, my job and learning new things that fortunately relate to my old hobby (radio-communications) and that is “C” programming with Arduino platform. The following picture depicts my last project.  A project that will help me, I hope, in making faster and better the work related to amateur radio. I learned alot from it: programming, precision mechanical assembling, CNC insights. In the last two years I was not quite a stranger to Amateur Radio. I made my own automated antenna rotor, DDS with several transceiver related functions and even an HF antenna analyzer – all based on Arduino. Hope I will have time to dedicate a little of it, again, to what gained years ago my interest.



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Looking for an interesting article I’ve just found this link:



I have just 3 poor looking pictures with my 6m beacon that is back “ON AIR” after a week or two of silence. Battery in the camera was down and I had no mood for recharge it in real time.
I moved the electronics in another box, of course an aluminium one, this time not “3 times smaller” but 2 times bigger🙂.
I made this move because i would like to have enough space for some later upgrades, like a 70MHz or UHF beacon this year.


Details are almost the same as last year (50.069.3 MHz, 3~4W, vertical dipole,  same KN17SP locator).

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Lower on this page, the spots listed acording to report.

YO5PBG 6m beacon features (actual):

  • Frequency: 50.070 MHz
  • Reported frequencies: 50.0690 ~ 50.069.9 MHz
  • Power: 3W
  • Antenna:  Vertical Dipole
  • Message: VVV de YO5PBG/B KN17SP———- (in loop)
  • Mode: A1A (CW)
  • Operating time: 24/24, 7/7

Date     Time RST Prop. (Comments)  Dist(Km) Spotter Spotter Loc

30.04.11 09:07 559 ES 559 es     1163 OZ1DJJ  JO65HP
21.05.11 11:33 559 ES  559          1200 DK1IZ  JO43RS
21.05.11 12:29 599 ES 599          1249 HB9DVH  JN36OE
22.05.11 07:44 539 ES 539           1711 G3VYF    JO01FN
22.05.11 10:41     ES                     1239 IZ8DWF    JM87AW
23.05.11 13:08     ES                     1239 IT9TYR    JM78QF
24.05.11 09:23 599 ES                 1239 IZ8DWF    JM87AW
25.05.11 10:56 329 ES                  1896 G4ENZ    IO81VV
26.05.11 17:49 559 ES                  1719 LA3EQ    JO28UX
31.05.11 12:07 579 ES       hrd     1407 OH5MD    KP20NG
31.05.11 12:23 579  ES                  1416 PA2J    JO21JO
31.05.11 12:25 539 ES                  1686 G3XGS    JO01KT
08.06.11 10:31 559 ES                 1389 PA2JWN    JO22QD
16.06.11 07:12 559 ES                 1389 PA2JWN    JO22QD
07.07.11 18:07 559 ES                 958 DL4MFF    JN57IW
08.07.11 07:47 559 ES               1360 PA5JS    JO21TP
08.07.11 07:48 559 ES               1416 PA2J    JO21JO
08.07.11 12:11          ES                906 DL3GER    JO62NH
08.07.11 13:37 599 ES  599+     1085 DK5YA    JN49NX
13.07.11 14:26 59  ES 59+++     1304 SV5BYR    KM46CK
26.07.11 09:01 579 ES               1442 PA5WT    JO22HG
29.07.11 09:10 579 ES               1081 YL2CP    KO27PH
29.07.11 10:26 569 ES               1156 DK2ZF    JO43VH
30.07.11 14:09 599 TR               586  E74A    JN93DU
30.07.11 14:13         ES hrd 1st   910  DK2EA    JO50UF
02.08.11 17:53 599 ES  bcn      1442 PA5WT    JO22HG
05.08.11 15:13 579 ES j bcn      1442 PA5WT    JO22HG
06.08.11 08:57       ES               1252 IZ1EPM    JN35TB
06.08.11 08:59       ES first time lsn 1252 IZ1EPM    JN35TB


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