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  1. HarryA1

    how to make a mailbox light? guys

    http://www.talkingelectronics.com/projects/SolarLight/SolarCharger-2.html
  2. HarryA1

    Bad quality breadboard?

    I got a package of 3 boards and jumper wires via Amazon.com and they are crap! Very difficult to insert the jumpers into. I also left my review of them and it was not nice. Also I saw a video on youtube.com where the instructor instructed the students to use needle noise pliers to insert the...
  3. HarryA1

    How long it takes to finish PCB assembly project

    You are not their only customer, they put you on the end of the queue. It takes me about 3 weeks to get electronic gear from China and it is already make!
  4. HarryA1

    Transformer for voltage booster?

    You points are well made; thanks. On day one I found two voltage boosters on Ebay that gave more than 100 volts so I ordered both of them from China. The first  one I received was a 12v dc to 200 v dc. After connecting it up and adjusting it for 200 v I put a 100k resistor across the output ...
  5. HarryA1

    Transformer for voltage booster?

    Hello from cold and snowy NE PA, In my quest to convert 9 - 12 volts dc into 140 volts dc I purchased a "40W DC-AC 12V To 220V Step-up Transformer Boost Module Inverter" via Ebay. I also purchased a 220 volt to 120 volt 50-60 hertz step down transformer; the type travelers use. But the...
  6. HarryA1

    100V 10A constant charging current circuit ?

    It maybe cheaper to buy one? http://www.ebay.com/itm/1200W-100V-DC-Switching-power-supply-for-LED-Strip-light-AC-to-DC-power-supply-/182370960410?hash=item2a7628041a:g:sukAAOSw6aVUn95M
  7. HarryA1

    Stupid pop-up window

    Is there some way to get read of the %^^*)(*^ pop up with " would you like to receive notifications.... ? I DO NOT WANT ANY!
  8. HarryA1

    What do you do with a 350 Farad capacitor?

    You could charge the cap. with  solar cells during the day and light an LED at night? No batteries required! see...
  9. HarryA1

    Light switch does not seem to work, only 60V measured at the switch

    Most likely you have a few screws loose John ;) see: http://en.allexperts.com/q/Electrical-Wiring-Home-1734/2009/6/Circuit-reads-60-volts.htm also  search on: "electrical problem 60 volts on 120" good luck. addendum: As this a common problem could a poor connection between copper (or...
  10. HarryA1

    n-chanel eMOSFET data?

    Thanks for the reply. I have a a 400 microsecond pulse every 20 ms that I wish to amplify. I need about 100 volts so I an thinking I need a 150-200v transistor. I need to preserve the varying amplitude so I can not just emulate it with a switching transistor. Speaking of transformers; I tried...
  11. HarryA1

    n-chanel eMOSFET data?

    Hello from NE PA, Where do you all find data on MOSFET transistors? I look on ebay  for MOSFETs but most do not have specs so you have to search for a data sheet, download it, open it, and find it's not what you want! I am looking for an n channel  eMOSFET for a class D amplifier that has...
  12. HarryA1

    TENS machines revisited

    Hello from NE PA, A question for you. How to TENS machines generate 40 to 60 volts from say 4.2 volts without using a coil or transformer? Pictured is a TENS circuit that is about 1.26 inches by 1 inch. The battery is on the reverse side of the board. thanks in  advance, HarryA
  13. HarryA1

    11.1 volts to 8.0 volts ?

    I picked up some LM317's today (1.5 amperes max.). Set the output to 7.0 volts and connected to a brushed motor. The motor drew 0.68 amperes. The output voltage dropped to 6.86 volts; the li-po battery output drop to 11.55 from 11.80 volts. This is with no load on the motor; I need to get...
  14. HarryA1

    11.1 volts to 8.0 volts ?

    Thanks. I replaced my diagram with the one from Motorola before seeing yours. I have power transistors coming from my favorite store - ebay. ;)
  15. HarryA1

    11.1 volts to 8.0 volts ?

    My "bright" idea is to use the mosfet to get more than the 1 ampere that the 8 volt regulator is rated at.  I have a large 11.1v li-po battery for the main motor so I don't want to add another battery to get the 8 volts. I wonder if one can put two or three regulators in parallel for more...
  16. HarryA1

    11.1 volts to 8.0 volts ?

    Hello all, I need to connect an 8 volt electronic speed control to an 11.1 battery. I have an 8 volt regulator and a power mosfet. I have not worked with mosfets before so I am puzzled on how to make the connections and what values of resistors are required. Please take a look at my diagram...
  17. HarryA1

    Checking new PC power supply

    Thanks guys. That's what I needed to know  :) I made a tester out off a 12 v brake light and a 6 volt one  ;)
  18. HarryA1

    Checking new PC power supply

    I have a new power supply that I would like to check before installing into the computer. On bench testing it I get no voltage at all. Is thid correct? I am thinking that perhaps there is some type of interlock so you only get voltage when it is installed? thanks in advance.
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