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HarryA last won the day on April 11

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About HarryA

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  • Birthday June 23

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    USA, Pennsylvania, Susquehanna Cty, Forest Lake
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    Canoeing, woodworking, electronics, and gardening.

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  1. That seems like a good idea. I gather that such refrigerators draw something like 5 to 7 amperes. A relay could handle that; such as: https://www.ebay.com/itm/NEW-Philips-ECG-RLY1522-12-Volt-DC-Coil-10-Amp-SPDT-General-Purpose-Relay/251877100313?epid=2282812589&hash=item3aa50b8b19:g:qVsAAOSw7ZFVAh~t I think one should put a diode across the relay coil (in reverse) to protect the controller.
  2. If you search on amazon.com for "arduino rf" you will find various transmitter - receiver options. Like this for example> https://www.amazon.com/WHDTS-Transmitter-Receiver-Transceiver-Communication/dp/B07L8RXSDF/ref=sr_1_36?keywords=arduino+rf&link_code=qs&qid=1574902183&sourceid=Mozilla-search&sr=8-36 for this model note: T400 Transmission Distance: 400M T400 Receiving Distance: 50M GWB Transmission Distance: 400M GWB Receiving Distance: 400M I do not see the differences between the T400 and the GWB units when ordering the units.
  3. Congratulations! Looks like you got read of the bad guys 😊
  4. Consider using this: "DC-DC Converter 3V-5V Output Step Up Step down Buck Boost 300V-1200V PSU Module" https://www.ebay.com/itm/DC-DC-Converter-3V-5V-Output-Step-Up-Step-down-Buck-Boost-300V-1200V-PSU-Module/264035829269?_trkparms=aid%3D1110001%26algo%3DSPLICE.SIM%26ao%3D1%26asc%3D20131231084308%26meid%3D303593509b5d4479a35466a0cb15c884%26pid%3D100010%26rk%3D11%26rkt%3D12%26sd%3D174073965556%26itm%3D264035829269%26pmt%3D1%26noa%3D1%26pg%3D2047675&_trksid=p2047675.c100010.m2109 If one monitored the capacitor voltage so when it got charged the battery was switched off and back on when it got low the average current drain on the battery would be acceptable perhaps. One could use JFETs and large (mega-ohm resistors) so the drain would be low on the capacitor. The converter would be switched on and off as it charged and recharged the capacitor; so the average current draw would be acceptable. Someone who knows JFETs better than I would be helpful here.
  5. Lets see if this is readable. Using a 2n2222 - about 10 cents apiece. Current from the source is 40ma with a base resistor of 1000 or 10k. In the view the yellow trace is the current through the relay; scale on the right . Green is the voltage at the base; scale on the left. I have no idea what the inductance would be so I set it at 0.001 henry.
  6. from: http://static6.arrow.com/aropdfconversion/ee14f7b4a3764f5a2d5bf5d73381b76d11c173d/3a3941-datasheet.pdf.pdf
  7. Medición de variables electricas modelo #2 (Measurement of electric variables model # 2) ¿Qué es el modelo # 2? (What is model #2 ?)
  8. I believe your circuit is not quite correct. The resistor and capacitor (C1 and R3 ?) belong to the DIAC not the TRIAC. see the circuit here: https://www.electronicshub.org/simple-fan-regulator-circuit/
  9. That is a good idea but how do you get the divide by 2.7 required ? Is the best one can do is to divide by 5 then by 2 or 10 and 4 for 2.5 perhaps. There is a good phase locked loop frequency multiplier tutorial at: www.youtube.com/watch?v=5by0os8RrFY
  10. The only way I can think of to do that is to use two circuits. First a frequency to voltage converter circuit. Then feed the voltage output of that circuit into a voltage to frequency converter circuit. One can find such circuits by searching on the internet. A circuit simulator would be helpful here. The 9400 chip can be used as a voltage-to-frequency or frequency-to-voltage converter. Perhaps there is a newer chip? Hopefully someone else will have a better idea for you 😐
  11. The vertical green line supplies current to the transistor. The other part of the green line supplies current to the detector which modulates it to form the audio and afc outputs.
  12. On my forum if you replace http: and keto one can at least alert guests not to click on the links and that may help. At least it is not difficult to implement. from my forum (note spaces around SPAM and SPAMMER - helps them stand out): Put the word to be censored on the left, and what to change it to on the right. http: => SPAM KETO => SPAMMER given: http://www.badguy.com => SPAM //www.badguy.com this is keto crap => this is SPAMMER crap Members posting url's in a post would learn to use the short version without the http: www.rcgroups.com Is spam the correct word or does that only apply to emails?
  13. You could ask for help finding a schematic here - maybe helpful: http://www.fixya.com/support/p143760-mge_pulsar_evolution_2200_esv22_ups Good luck.
  14. the manual is here if that is helpful: https://www.manualslib.com/products/Mge-Ups-Systems-Pulsar-Esv-22Plusrack-1938198.html
  15. If you open the register page and right click on the page and select "view page source" you see the html code that makes that page. If you search on that code for: "form_q_and_a" you will find the block of code that renders that area on the page.(in firefox search by ctrl+ f) and that contains your question. If one is comfortable with working with files on the server one can find the file that contains the "form_q_and_a" string. then download it to your pc and replace the text string with an image ( jpg or png file ) of the text in mixed colors and fonts. If you don't have the tools to create such a file I do. You may not see you text string in that file as it maybe added in at run time. In my first forum I got to the point that I would register members via an email request myself; they where not allowed to do so. I used their requested user name and assigned them temp.password and that works well if you do not have many request per day. It beats having to clean up the forum everyday.
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