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  1. HellasTechn

    Serial communication problem.

    A simple repeat option :) like a checkbox that i can deselect when i want transmission to stop repeating.
  2. HellasTechn

    Serial communication problem.

    I have one question concerning serial terminal software for PC. Like the TERMITE, but i need one that will be able to repeatedly transmit the sentence i write... The TERMITE is very good but will only transmit the text i write once, then i have to write it again and press enter. Is there some...
  3. HellasTechn

    Commodore 64 Murder Mystery - The power supply

    Well what can you say... I used to consider the power supplies with transformer, more reliable. Theese are just badly disigned power supplies...
  4. HellasTechn

    Hello, Welcome! (Introduce yourself)

    Hello ! Welcome onboard !
  5. HellasTechn

    Serial communication problem.

    I suspected that but to be honest i thought that unless differently specified, we use conventional current flow.
  6. HellasTechn

    Serial communication problem.

    I came across this video on youtube that explains about transistors. I have a question. At about 7:30 on the video he shows current flow in a pnp transistor and from what i understand, he is suggesting that current flows from emmiter to collector. Is my understanding wrong or is it something...
  7. HellasTechn

    Serial communication problem.

    Yes thats right. What i ment was that this is the signal i am feeding to base through the resistor. Like i suggested here: I also had no idea there was such thing as reverse mode. But then again is it the first or the last thing i have no idea about ? I am a complete noob compared to all you.
  8. HellasTechn

    Serial communication problem.

    Thats is because the transistor will not be fully turned on. will probably be within the "active region" if i that is the correct term in english. Am i wrong ? I look forword to that sir Chris. I have to let you know though that i will be away for work for the next 6 days without internet...
  9. HellasTechn

    Serial communication problem.

    Ok sir. theese are from the bc547. Picture 1 = input pin while not connected to the transistor. Picture 2 = with collector to gnd Picture 3 = with emitter to gnd. Channel 1 = input signal (at base of transistor) Channel 2 = output signal Notice that when connected to the base of the...
  10. HellasTechn

    Serial communication problem.

    Ok. theese are from the bc547. Picture 1 = with collector to gnd Picture 2 = with emitter to gnd. Channel 1 = output signal Channel 2 = input signal
  11. HellasTechn

    Serial communication problem.

    I will right now. I will post back in 5 minutes.
  12. HellasTechn

    Can it be saved

    Or the supply just died and there is a protective diode on the PCB that will not allow current to pass due to reverse bias.
  13. HellasTechn

    Serial communication problem.

    I have builded the circuit exactly as pictured in post #61 and used the Oscope... The base through the 10k resistor was connected to the 5V 1Khz scope's output. The resaults are pictured below. What i found is a perfectly shaped 5V square pulse 180 deg inverted compared to the input square...
  14. HellasTechn

    Can it be saved

    There may be some other bad component.
  15. HellasTechn

    Can it be saved

    That looks like a missing DC jack. As far as i can see it looks like there is nothing wrong with the PCB. you just need to solder a new one.
  16. HellasTechn

    Serial communication problem.

    Yes i do have one. It actually confirms that the BC547 i have are CBE and the 2N2222A are EBC. Today i found some time to play with this project and i discovered that the picaxe does not understand half of the data i send to it. So indeed i will need to reverse the BC547 to correct direction so...
  17. HellasTechn

    Serial communication problem.

    The BC547 i have are CBE and the 2N2222A are EBC I had no idea about different versions either Though i have seen the TO-18 one.
  18. HellasTechn

    Serial communication problem.

    Now that is strange. I have the PCB connected as shown in picture #61. Now with the 2n2222 (TO-92) (they are actually marked 2n2222) my picaxe can not read the ttl signal while with the BC547 in the bace (face same direction as 2n2222) meaning collector to ground and emitter to +5V then the...
  19. HellasTechn

    Serial communication problem.

    10K each. P.S. It's fine as long as it works !
  20. HellasTechn

    RS422 to RS232 converter.

    It looks very simple and with no external components needed. :)
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