Search results

  1. Old Steve

    RF controller relay help

    Ready for a long reply? :- Q1 turns on the relay that operates the motor in the forward direction, (closing the valve), and Q3 turns on the relay that operates the motor in the other direction. Q2 senses the current flowing through the motor via R7, so that when the valve reaches the end of...
  2. Old Steve

    DT9205A multimeter fault in voltages measurements

    That model only has a fuse in the current measurement circuitry, according to the manual. Just the lower current ranges, too, not the 20A range. The manual:- https://arduino-info.wikispaces.com/dt9205a-multimeter-manual
  3. Old Steve

    LED Circuit not behaving as it should

    Are you 100% sure that the cathode of the zener is connected to gnd, and not to the positive rail of the output voltage? That would make more sense.
  4. Old Steve

    DT9205A multimeter fault in voltages measurements

    Did you put a battery in it?
  5. Old Steve

    RF controller relay help

    Here's one possible solution using a geared DC motor , only a crude first draft so far:- (This uses a 'no data' version of the PT2272, with the Vt (valid transmission) pin operating the motor to close the valve.)
  6. Old Steve

    RF controller relay help

    That sounds much better. I was picturing something like this:- And if more than one turn of the shaft is needed, a servo is definitely out.
  7. Old Steve

    RF controller relay help

    As mentioned in the edit of my last post, if you do a quick sketch of your valve setup, I'll think about it tonight and see what I can come up with. I don't think that you necessarily need to go as far as a micro and programming, but we'll see.
  8. Old Steve

    RF controller relay help

    Sorry, I can't definitively answer that, although it will probably have enough torque. It's really a matter of trying it, then going to a larger servo if it doesn't, I guess. Regarding the pulse stream question, a servo is driven by a stream of pulses at 50Hz, with 1.5mS pulses centring the...
  9. Old Steve

    wireless UART or USART

    I missed your original post, and only just found your second. Is P925.00 in Indonesian rupiah? If so, that equates to a very high price for these modules, USD$61.75 or AUD$97.79. I use very similar modules bought for a much lower price than that. Try eBay for APC220 modules. For example, the...
  10. Old Steve

    RF controller relay help

    No problem. Glad to help in any way I can. I just got back into electronics after some years off, so it's all good practice. Luckily for you, one of my first projects involved RF remote control using the PT2262 and PT2272 chips.
  11. Old Steve

    RF controller relay help

    Henry, in my haste I forgot to put a protection diode across the relay, to protect the transistor when the relay turns off. I suggested a 1N4002, but any 1N400x diode would do, or even a 1N4148. Here it is:- I just looked more closely at your motor. It complicates things, being an RC servo. A...
  12. Old Steve

    RF controller relay help

    Here's the matching receiver:- . Also, here's a link to the PT2262:- http://www.utsource.net/ic-datasheet/PT2262-809208.html And the PT2272-L2:- http://www.utsource.net/ic-datasheet/PT2272-L2-683892.html
  13. Old Steve

    RF controller relay help

    Henry, the PT2262 needs a minimum 4V, but the strength of signal is unimportant with a coded 3^10 setup, since nothing else will respond to the signal. My schematic suggests a 12V supply, a small 23A battery, but anything above 4V would do the job. Here's the transmitter schematic. (Receiver to...
  14. Old Steve

    RF controller relay help

    What sort of RF transmitter and receiver do you have? Pics maybe? RF noise and false triggering are likely to be a problem. You could use a PT2262 remote control encoder IC connected to the transmitter, which allows you to set an address code to avoid false triggering, then a PT2272 remote...
  15. Old Steve

    resistor blown frequently

    Did you replace the MOV? If it's dead, the resistor will most likely keep burning up. I found the service manual, but in their wisdom they don't include the PSU schematic, just everything else. Here's the manual, FWIW, (you'll need to download the free DejaVu viewer to see it though):-...
  16. Old Steve

    I need help with a DC voltage regulator circuit

    As Harald suggests, this is really a job for a microcontroller. If you're already familiar with php and Javascript, it's not a big jump to C, C++ or even simple basic. PICBasic or C with a PIC uC is my weapon-of-choice. (PICBasic Pro from MicroEngineeringLabs.) The Arduino is very popular these...
  17. Old Steve

    and/or logic gate + flip/flop question

    No worries. It's operation is a bit confusing at first.
  18. Old Steve

    and/or logic gate + flip/flop question

    I ran the simulation and it works as described. Surprisingly, pressing 'Clear Alarm' doesn't turn off the visual alarm unless 'Acknowledge' is also pressed, but that's how it's supposed to work according to the description. ('Clear Alarm' only stops the audio alarm and not the visual one.)...
  19. Old Steve

    PT2272 Supplier - No data version - (3^12 address)

    Finally, after days of searching, I found a supplier of these chips - http://www.utsource.net/search.aspx?keyWords=PT2272 They have all variations from 0 data bits, (12-bit address), to 6 data bits, (6-bit address), in both momentary and latching, PDIP and SOP. US$0.45 each for the PDIP. Only...
  20. Old Steve

    ESAB A10 160K PCB

    I just did a search of these forums and found an old thread with some replies from a fellow member who worked for ESAB for 20 years and might be able to help if you can PM him. His name is bobbes, in this thread:- https://www.electronicspoint.com/threads/esab-a10-160-mig-welder.129849/
Top