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  1. HellasTechn

    Can I store TV circuit boards in Ziploc bags

    You can very well use ziploc bags only if you carefully wrap the whole pcb with aluminium foil. Just make sure you leave no gaps.
  2. HellasTechn

    A question about cross talk! :)

    What i say may be wrong but it sounds more like EMI to me rather than cross talk. Basicly we talk about the same thing in other words. this interfearence is caused by nearby cables. Putting your circuit on a properly grounded PCB with a good ground plane should eliminate the problem.
  3. HellasTechn

    555 on/off circuit for 5v motor (w/ schematic)

    One thing i would like to point out here is that the 555 circuit is not reccomended for frequencys smaller than 1hz. a cheap microcontroller like the picaxe 08m2 would be a good choice for that project. The code for such task is extreamely easy and the outcome would be very satisfying.
  4. HellasTechn

    Lead Acid Battery(gel Type) Getting Fat And Losing Its Capacity To Hold Charge

    I dont think it is a good idea to keep them. Also i am not sure what chemical reaction goes on inside them that make them "fat" as you say. Best thing to do is to charge them periodically like once every month for a few hours to make sure that their voltage never drops below 12V.
  5. HellasTechn

    FOG MACHINE REMOTE CONTROL PROBLEM

    It may be possible that you can order them Via E-Bay at really low cost. Sourceing parts is a problem all around the world. except maybe china, im not sure.
  6. HellasTechn

    FOG MACHINE REMOTE CONTROL PROBLEM

    Here is the simplest answer that will fix your problem, given that the problem is indeed the remote control. Your PCB is roughly consisted of 2 IC's 3 buttons, 1 transistor, 5 diodes, 1 zener diode and a few other parts that hardly ever fail. Why dont you just order the two IC's, transistor...
  7. HellasTechn

    SMD components question.

    I see your point now. You are right. Still a Q could be a bjt, mosfet, thyristor and more. It is better than nothing though.
  8. HellasTechn

    SMD components question.

    most PCB's iv'e seen only state the id e.g. U1 or R112 and if you dont have the service manual or the PCB schematic...
  9. HellasTechn

    How can we Improve EP in 2017?

    I understand your point. Yesterday for example i was discussing with Sadlercomfort about some program codes and we had to go back and forth between ep and facebook to write pices of the code and comments It's good to be able to go back and review but it is also nice to have a chat room to share...
  10. HellasTechn

    SMD components question.

    Yes. The problem is that it can be anything. there are no stantard marking. For example a TO-92 2n2222 is a transistor no matter who the manufacturer is while a SOT-32 Y1 could be a diode or a transistor or a regulator. Got the point ?
  11. HellasTechn

    How can we Improve EP in 2017?

    I would personaly like to have the chat room to use it for real time assittance. For example now that i am learning to use picaxe commands i would like to be able to talk in real time with friends in here that can provide me with guidelines.
  12. HellasTechn

    TV Samsung LE32B450C4W bad PSU.

    I think i got your point. Here are two more pictures. I suspect a bad PCF chip also. (FAN 7530). I will go get a new one later today when shops are open. samsung is also know to have issues with the power diodes.
  13. HellasTechn

    Fixing an HP3455A multimeter

    Ok. I think i understand.
  14. HellasTechn

    Howdy all.

    Ho ok. :)
  15. HellasTechn

    Howdy all.

    I also work on shipboard electronics some times. I am definetly far from expert but i try. I understand that a hydrophone needs a preamp but the preamp needed a submarine ? Or the hydrophone was needed on a sub ? I know all subs have hudrophones and most surface ships also to communcate with subs.
  16. HellasTechn

    Fixing an HP3455A multimeter

    Probably some ignorant person was bored enough to go buy a new cap and decided to terminate a well working unit. I would also check the same cap on the other unit also just out of curiosity.
  17. HellasTechn

    Howdy all.

    Welcome to our forum friend ! All the above sound like shipboard electronics to me. Am i wrong ?
  18. HellasTechn

    TV Samsung LE32B450C4W bad PSU.

    I have taken pictures and measurements. Here is a table exactly as shown on the PCB but with the readings i got. as far as i can tell DET_5V is wrong and i am not sure about I-PWM and E-PWM.
  19. HellasTechn

    TV Samsung LE32B450C4W bad PSU.

    Hello friends, I am looking at this Samsung LE32B450C4W television that would blow the PSU main fuse when connected to MAINS. I found the bridge rectifier Shorted and a blown mosfet (QP802s K10A60) i replaced both (actually the K10A60 with a K15A60) and the mainboard comes on. I hear the...
  20. HellasTechn

    220V solder iron under 110V

    No there is no thermostat. Just the heating element and the 1n4007 in series. It is a cheap (probably chineese, i am not sure) solder iron. It actually runs quite well on 220V. the heating element is probably a 40W and the diode is there to keep it from burnig up i assume. I am definetly not...
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