Search results

  1. Externet

    Meaning of square symbol ?

    Hi. What does that faint square shown left of the date on any post means ?
  2. Externet

    a transistor is a variable resistor

    I will have to spank the writer/teacher of my first book on the subject. From random finds, ---> https://www.coursehero.com/file/85767335/Introduction-to-transistordocx/ ---> https://qa.answers.com/Q/Why_transistor_is_called_transfer_of_resistor --->...
  3. Externet

    a transistor is a variable resistor

    That is like what my very first transistor learning lesson said when I was 12. Transistor = transference resistor.
  4. Externet

    Sturdy DC power jack

    Consider XLR connectors too. There is four pins type also to ensure redundance, and bulkhead. Same with speakon connectors. Perhaps you can use simple RCA type too.
  5. Externet

    Help needed to build a Simple radio to generate a tone

    COL. Carrier operated light / carrier present light, LED. ?? Squelch indicator, carrier indicator, added LORA... If there is no path for the RF link, nothing can be conveyed. If the thing is inteligibility, well, PTT to COL.
  6. Externet

    Where to buy shielded jumper cables?

    First result of a search shows Walmart...:oops: ---> https://www.walmart.com/ip/BNC-Male-to-Male-Coaxial-Jumper-Cable-50-ohm-10-feet-RG174-2pcs/821328750 I have half a dozen to interconnect test equipment on my bench.
  7. Externet

    Unlicensed Radio That Will Transmit Continuously

    I know some gals that never hang up their phones with no remote clue of what transmitting licensing is; and plenty of WiFi on in every home 24/365. But when I want to transmit intermittent conversations on amateur radio I have to identify like once a minute and pass trough the funnel of...
  8. Externet

    Step Down transformers, will they harm an electronic machine?

    Cannot believe there is no coffee makers in Palestine stores other than the Amazon choice.:oops:
  9. Externet

    battery pack question

    Each cell must be voltage probed and its ends sanded to ensure contact. Any open cell or contact will prevent the pack to recharge. A heating what? charger or cell? can mean shorted cells. What is the 'wall wart' measured output voltage ?
  10. Externet

    battery pack question

    If the battery pack has a charge controller circuit inside; it may be preventing from charging by either a failure, smoke missing; corrosion, a broken battery connection, a weaker than limit-discharged cell. Measure each, inspect and come back.
  11. Externet

    tic tac on transformer chopper from satellite receiver

    Disconnect the antenna LNB coaxial connector and check if the restarting 'tic tac' persists. If not; the coaxial cable, connector or LNB is faulty.
  12. Externet

    Tweaking an analog VU panel meter ?

    Hi. In a playing attempt to make a quick dirty solar pyranometer indicator, connected a plain garden light solar cell to a VU meter canibalized from defunct equipment, to see if would indicate something reasonable. (-)Solar...
  13. Externet

    Opinions on This Oscilloscope

    Bought that one a few months ago from curiosity. It works, it is accurate. I get lost constantly tying to find settings and controls as it is a new animal to me given little use so far. I added some labels to front panel to ease locate functions/knobs. Tempted to glue it to a brick to make...
  14. Externet

    When does a fuse or circuit breaker blow

    A breaker or fuse protects wiring. Does not protect a DC current source as a solar panel. If a wire inside a panel opens from overcurrent; the wires inside that panel are under what is needed, it is a poorly designed panel. The opening of a wire in a solar panel under load likely produces...
  15. Externet

    When does a fuse or circuit breaker blow

    Because the current did not reach 25 nor 20 Amperes. The 100A is/was the supply capability of the battery; not what it 'puts out' Did you measure the voltage of the battery when you connected it ?
  16. Externet

    Chosing a Microscope

    Attach anything to the wall that this type of telescopic lamp base can grab onto.
  17. Externet

    Chosing a Microscope

    ---> https://www.ecosia.org/images?q=drawing desk lamp Usually found in the janitor closet of a large office in beheaded condition behind spider webs or in the dumpster for $0 cheap; -but you do not need the lamp head anyway- Attaches to the bench/table edge.
  18. Externet

    Battery Charger rewire help

    IF the regulation control circuit has a problem. Modern battery chargers have circuitry to recognize the battery to be charged is good and not a defunct thing extracted out of the backyard weeds. Can easily mislead users. Before performing any surgery, try it with a known healthy battery...
  19. Externet

    Samsung 2017 Smartfridge component missing

    Most appliances have their schematic attached somewhere in the back. Spare part vendors publish them too. Youtube may show something also.
  20. Externet

    What transistor is this?

    Always seeing plenty of all brands used coffee machines in thrifty stores, peddler's malls, facebook marketplace... visit them, perhaps you get lucky if all else fails.
Top