Search results

Search Forums New Posts
  1. D

    define a variable in header file

    Side comment, be careful with variable add / declare in header files. If IDE is generating the file it can overwrite your declaration, so make sure you know what your tool is doing. Also make sure you use the modifier "extern" where appropriate...
  2. D

    Switching Power Supply Short

    Are the two large caps bulging at top ? cant tell from pic but if they are could be damaged. When caps go they take other parts with them. Look on youtube, lots of videos repairing SMPS, troubleshooting methods, hints..... Regards, Dana.
  3. D

    ttl and hall sensor

    Microswitches also used on CNC limit detection : Usually chained together in series on mill, NC switches, and if anyone breaks mill stops. Use as a logic signal to mill controller board. Regards, Dana.
  4. D

    ADC Values

    T sensors down to +/- .2% accuracy : https://www.digikey.com/en/products/filter/temperature-sensors-thermostats-solid-state/564?s=N4IgTCBcDaIC4FMC2AHBAnAhnAruhABAM4IB2RA9uiALoC%2BQA Regards, Dana.
  5. D

    1000V DC 25Amp voltage regulator

    These folks do some hi power stuff including assemblies : https://www.littelfuse.com/~/media/electronics/product_catalogs/littelfuse_power_semiconductors_product_catalog.pdf.pdf Regards, Dana.
  6. D

    Battery resurrection

    Actually there are videos on YouTube showing battery flush to remove some of the oxides. There are even videos where plates are removed and case cleaned. Video's where shorts were removed with very high current, not exactly rocket science in the positive sense. None where actual engineering...
  7. D

    Battery resurrection

    Take a look at a number of videos on Youtube. I have used recently epsom salts on on a battery and recovered most of its capacity. Regards, Dana.
  8. D

    ADC Specifications

    This would be a good start to answering many of these questions : https://www.analog.com/en/education/education-library/data-conversion-handbook.html Regards, Dana.
  9. D

    Tektronix 2430 repair

    This sounds like a firmware issue where no controls are being responded to. I would raise slightly then push back into socket any socketed IC for starters. Look for loose PCB screws, especially ones that are path for grounding. Clean connectors and flat ribbon cables. Be careful and extremely...
  10. D

    555 LED Circuit not playing nicely

    Bat1+ and Bat1- are connections to power source, battery. Regards, Dana.
  11. D

    L.E.D testing

    Common test is to test for brightness to match them for consistency in displays and signage..... For that a simple photocell can be used, force a known current thru each, and measure the brightness (photocell resistance). Multimeter diode test forces a current thru DUT and its V measured. But...
  12. D

    555 LED Circuit not playing nicely

    Keep in mind the tolerance of electrolytic is awful, in some cases > 100%, so if timing off first suspect assuming you use 5% or better R's. Add to that timing accuracy CMOS 555 is ~ +/- 10% (ideal R and C)...
  13. D

    Have trouble figuring out what's wrong with the 220v inverter.

    Google "inverter design application note", lots of designs and help. Many papers here - https://archive.org/search.php?query=inverter+design&sin= https://www.amazon.com/Power-Inverters-practical-construct-sine-wave-ebook/dp/B08N6TT5X9 Because of complexity (magnetics considerations, HV...
  14. D

    Have trouble figuring out what's wrong with the 220v inverter.

    Do you have a pic of prototype ? An IRFZ has large input C, a 4017 cant properly drive it. Where did this schematic come from ? Your 4017 cant provide adequate dead time timing ......Do you have a scope so you can look at timing ? You have no gate L supppresion resistors in circuit...
  15. D

    Analog signal amplifier with OpAmp, Transistor or Darlington Pair?

    Tools : https://www.ti.com/lit/an/sloa030a/sloa030a.pdf https://www.ti.com/lit/an/sloa097/sloa097.pdf https://www.ti.com/lit/an/slyt189/slyt189.pdf Non-Inverting Op-Amp Resistor Calculator Op-Amp Voltage and Gain Calculator...
  16. D

    Can someone help me with this

    Is that R cracked, upper right I see a faint line in body.....? Clearly the Transistor suspect, is it shorted ? Hand draw the connections to the transistor to see what base or gate drive looks like. That could be a clue as to mosfet or triac or scr or transistor. No markings on transistor ...
  17. D

    Wien bridge oscillator help...

    Seems like a large deviation. Cant rack that up to stray C at this freq. Which R is being adjusted ? Obviously check the sim is using same R total in the applicable circuit branch. What does the spice model for the pot look like ? Regards, Dana.
  18. D

    Wien bridge oscillator help...

    How much of a deviation in freq ? What freqs are you seeing ? Post a pic of your prototype and schematic..... Regards, Dana.
  19. D

    Resistor inside an inductor.

    Possibly a spice sim might help : https://www.diyaudio.com/community/threads/spice-modeling-acoustic-properties-of-speakers.321621/ Regards, Dana.
  20. D

    Resistor inside an inductor.

    That coil is not wound on the resistor. Is it for dropping the coil Q ? Regards, Dana.
Top