T&L Publications

What do you consider better?<p>A switching power supply has better regulation and is more efficient but has a more complex circuit<p>A half wave rectifier is is very simple and least expensive but has more ripple but is fine if the application circuit dosen't care. Generally requires filtering<p>A h...

Best you can get from a fab on 2 layer would amount to about $75 for 5 boards shipping included delivered in about 2 weeks. This covers 2 layer standard process up to 20 square inches and it's not much more for 10 boards (sometimes the same).<p>Several fabs offer this similar low pricing on "Pr...

On Trace Thickness:<p>If you are using a board house (Fab) to make the boards; 7mil is the thinnest you want to use because smaller will kick you into a higher price bracket.<p>Since 7 mil is still quite thin, I use 14mil or 21 mil for most of my signal traces and 30, 50 or 100 mil for most power co...

My generalized advice:<p>A good library is important but even the best are incomplete. So, what's really important is a good library editor that makes sense to you and is not wrapped up in too many layers of files. A via or thruhole wizard is helpful also.<p>Simulation sounds cool and can be quite u...

Though I couldn't find the free website (and I do think there is one) I did find this software www.airnavsystems.com <p>If you setup a radar at the end of a runway, you would probably hear from Homeland Security before long anyway. I can't believe they suggested that. It might be illeagal (not sure)...

Most battery types will leak but usually after they are long dead and forgotten inside of a device. Heavy duty batteries are notorious for this. <p>"Weeks ago" (even 27 weeks) should be well within the storage life of alkaline but extreme conditions (rough handling, very high/low temp, fas...

Is this an idea for a home business or are you just looking to find a cheap source of parts for yourself?<p>Dosen't sound like something that can be made in USA for low cost. Might have to look at asian markets to find an OEM wholesaler.<p>Any seller in the US consolidating components specifically f...

Maybe you can find an old Oscilloscope and operate it in X-Y mode. You would still need to hack the intensity knob to display the Z component. Scaling the input to match the display should be a snap.<p>Older analog scopes tended to suffer from wearout of the mechanical selector switches. You may be ...

The easiest to use displays (and they are relatively cheap) have driver electronics built in. They can be as easy to use as writing data into an 8b static RAM. All you need to do is put the proper binary word on the 8 bit input pins and pulse the clock pin and repeat. Some also take serial input but...

Substitute human bodies for the lemons and you have "The Matrix"<p>Lemons are a bit weak for earth but.... Assuming your robot planet has plenty of elemental copper and other metals lying around on the ground (as it must have to spawn robots as a life form) then the Lemon trees would suppl...

Those tiny race cars have 4 channel remote recievers and run on very low voltage. You may need to buffer the reciever output with a transistor since the lights probably use more current than the origonal load of the motor. The transmitters tend to be rather large though.<p>I like Dale's idea of a no...

Maybe what was meant is that there are many chips which have the same or similar functionality as the 4017 decade counter.<p>While there are probably more than several manufacturers of the 4017 chip, they should all work the same. The letters surrounding the core part number may signify the manufact...

I don't see why you couldn't incorporate a PIC into a geiger counter circuit. You'll still need the tube.<p>Start with this schematic as the front end: geiger counter schematic The upper portion on the schematic is used to bias the tube (500V) and the output signal comes down to C6 where it is coupl...

To inject your small signal (low amplitude, high frequency) onto the power line (large amplitude, low frequency) you need a series capacitor. One that would be an open (high impedance) at 50/60Hz but be low impedance at the carrier frequency (assuming FM)(AM could cause interference with other thing...

If you use this circuit, you should replace the relay with a FET or select a relay with the highest coil resistance you can find (and still closes at 12V).<p>While K7elp60 needed a low contact resistance for a high current load, you do not. The relay coil is powered whenever the load is powered. The...