Remote controlled flashlight?
I would like to be able to turn a flashlight on and off with a wireless remote from about 20' away (or so). I figured if I get one of those big plastic flashlights with the 6 volt battery there should be room for whatever electronics are needed, but I don't know how to do it. I realize this sounds like a bit of a... 13 Aug 2010 02:46
Ping JB (ThinAirDesigns)
JB, I posted the following a while back, but haven't seen a reply. Maybe I missed it or maybe you missed my post? "While I've got your attention: Maybe it's just me but, with no rancor intended, something seems to be amiss with a couple of the the videos on your website. 1. In the first video, DDW.MOV... 11 Aug 2010 15:50
unstable opamp ringing oscillating and such
can anyone in here explain why a OpAmp could oscillate or become unstable if there are 2 poles before it reaches 0dB on a plot of gain vs frequency? Here's what I've gathered thus far... there's a cap internal to the op- amp, that cap is there for some reason and it puts the dominant pole in the op-amp's transfe... 13 Aug 2010 16:52
Buffered FET logic, Direct coupled FET logic tutorial
Could some electronics guru provides some URLs for authentic buffered FET logic and/or direct coupled FET logic ? Thanks in advance. ... 13 Aug 2010 14:41
Why such wide price difference in fuses?
I was looking for a 0.75 to 0.8A fuse for a PSU I've built and there's a very wide price difference in what seems to me to be similar fuses. I've been curious as to why this is the case for a while. For example this fuse 0.8A SLO BLO 5 X 20MM IS only $0.670 http://www.littelfuse.com/data/en/Data_Sheets/239... 11 Aug 2010 10:21
Device on cable
Cables which connect USB ports with peripherals such as cameras frequently have black cylindrical objects on the cables a few centimetres away from the USB end. These may be about 10mm in diameter and 20 mm long. Are these things ferrite beads used to eliminate stray pulses in the cable or something else? If... 11 Aug 2010 21:23
Correcting for Impedance Errors w/o Superposition & FFT
If you already have the frequency response of the impedance of a circuit over a bandwidth, it should be possible to largely correct for differences in the reactance of a similar but less-than-perfectly- known circuit by applying a wave form which is a sum of one or several frequencies that fall within the known ban... 11 Aug 2010 10:21
test -- JF ... 8 Aug 2010 18:55
Are rechargeable ALKALINE CELLs still available?
Some called 'grandcell' which I've used for 2 years need to be replaced, but they've gone off the market here. Have these [made in Malaysia] been banned, or what ? ==TIA ... 13 Aug 2010 17:58
Cordless drill power supplying scooter motor?
Does this sound right? drill battery and controller no-load driving the drill motor lowest-speed 1 amp full throttle 2.8 amps driving the scooter motor lowest-speed 1.5 amp full throttle 10 amps What concern is there about the cordless drill speed controller (trigger stuff, PWM, whatever) overhe... 11 Aug 2010 19:09
LCD Without Wire Connectors
I have a Radio Shack count-up/count-down timer, catalog #63-878. It's about 2.5"x3.2"x0.70" thick. It's around 10 years old and some of the input keys had become sticky. I had to remove the back, then remove the circuit board which was held in by four screws. As I gingerly removed the circuit board, the LCD... 9 Aug 2010 02:31
How can design analog SPDT switch which switches VCC between +3.3V and 5V depending on application? I've an available pin on micro which can select the VCC. There are some ICs available to do this job but I would prefer to do it FET or Transistor. Anybody has idea or circuit? Thanks ... 11 Aug 2010 13:39
36v power tool motor to replace scooter motor?
Does this sound right? motor shaft revolutions per scooter wheel revolution 8.15 wheel circumference 39.27" wheel movement per shaft revolution 4.82" motor shaft revolutions per minute (estimated) 3500 inches traveled per hour 1,011,900 inches in a mile 63360 miles per hour 15.97 I am pretty sure tha... 7 Aug 2010 19:05
low frequency amplification
Hello, I have a question about where do frequencies end and pulses start? I'm trying to make an impact detection circuit, I have some sensors on a mat, and when something strikes the mat I get a small voltage (like 100mV).... so I'd like to amplify this 100mV to something around 1V.... I've been reading up ... 6 Aug 2010 21:29