Search results

  1. B

    What thermal fuse do I need.

    Careful there, need to shunt the heat with needle nose pliers or the like otherwise end up destroying the new one. Most are crimped in place.
  2. B

    Trying to reconfigure this jump start/peripheral connector cable thing

    No reason why the image could not be reduces to less than 100kb and still be readable if not unable to work out what you want to do. No idea what you refer to as "in series ,right?". What is an SAE connector..??
  3. B

    Help - Mystery Outlet! Photos & Video

    Wiring most likely has been a switch only . Appears no neutral and someone has decided to put a socket in there which obviously will not work. Metal wallbox, no earth presumably and rubber braided cable.......thought i'd seen the last of that old stuff 25 years ago. NoContact tool is not...
  4. B

    synchonizing speeds of two dc motors.

    I'd go Harald's point 4.
  5. B

    120vac to 0-90vdc motor drive

    But the motor would require both armature and field........has this been modified or is the motor permanant magnet..? Do you have control voltage...12v..? Your diagram does not show any power supply for the former. Been a while since I've seen unijunction transistors used...must be old as...??
  6. B

    synchonizing speeds of two dc motors.

    Optical encoders on both motors, compare pulses and adjust accordingly. There may be lag in the adjustment to the actual speed correction so would need to consider that. Micro controller is one type of monittor and adjustment route. Old tape drive motors and record players used mechanical...
  7. B

    120vac to 0-90vdc motor drive

    Think there is more to the diagram. Lower and top centre shows termination for field coils. Where are you taking your measurements from..?
  8. B

    Help me with Outlet & Switch? I've got nice pictures for you!

    When working with mains it is necessary to test before and after isolation with an approved meter to ensure wiring is indeed isolated from the supply. Then when work is completed, additional testing is required to ensure correct polarity, breaker operation and earthing is in place. I would...
  9. B

    LM339/LM339N can't get output high

    there is no pullup on an lm339...it is open collector so I suggest you do some reading
  10. B

    LM339/LM339N can't get output high

    It depends on how you have your inputs as to what happens when one input or the other goes to a higher level. The output still works the same but the LED will be on either when the "+" is higher or the "-" is higher level. You will notice one is marked "-" and the other "+". If the "+" input...
  11. B

    VDO Voltmeter

    Post a complete schematic while you are at it. Those fritzing things are useless.
  12. B

    VDO Voltmeter

    Ah..ok....m Ah...ok....misread on my part. Will think a bit more on it. If it is basically a current issue then boost the handling ability with say a mosfet for example. Show us a circuit what you presently have.
  13. B

    Load auto-detect

    Old Lister and similar diesel generators used to use dc detect systems but were mainly for lighting i.e. detecting bulbs etc. Used to work on these but cannot remember the actual circuit schematics but do remember they incorporated relays etc. and not as simple as you might think. Main aspect...
  14. B

    VDO Voltmeter

    Why not use a boost converter...adjustable. https://www.ebay.com.au/itm/MT3608-Step-Up-Adjustable-DC-DC-Switching-Boost-Converter/383810533918?hash=item595ce3fa1e:g:ef0AAOSwwnVcd903
  15. B

    I am curious what part do they substitute for a mercury float?

    Tilt switch...... there are module units for use with Arduino also (Ebay eyc) https://core-electronics.com.au/tilt-switch.html?utm_source=google_shopping&gclid=EAIaIQobChMI5Ja8hqTU7gIVEjdgCh13FwBeEAQYAyABEgJbL_D_BwE
  16. B

    LM339/LM339N can't get output high

    This was taken from the LM339 data sheet....... 5.1.1 Do Not Connect Inputs Directly to Ground For both used and unused comparators, the inputs must not be connected directly to ground or any other low impedance node. Always add some resistance to limit the current to less than 10 mA...
  17. B

    Why is it PNP instead of PPN for transistors

    Talkingelectronics have a simple amplifier test on a transistor that shows exactly that.
  18. B

    Three way switch selection for switching aux phono output

    This type of thing. Available in either make before break or break before make...
  19. B

    LM339/LM339N can't get output high

    As pointed out, the output will be open collector....so turn your LED around and place the anode of the LED to the positive supply and the cathode to the resistor. Do not see why the unused inputs and outputs are at ground, just leave them.
  20. B

    LEDs and water and moisture ingress

    Forget the holders, silicone seal the LEDs into the holes from the rear. Or use LED strip. Many used for auto application and are waterproof. Just need to get the connections into a dry location.
Top