T&L Publications

There are two methods to charge SLA batteries. One is the cyclic, in that you charge the batteries at 2.4 to 2.45 volts per cell and at a current of capacity times 0.25. In your case this relates to 28.8 to 29.4 volts at maximum current of 17 amps. Once the charging current drops to .01C or .68amps ...

How about putting some regular silicon diodes in series with each supply leg, at the rated current.
That way only the voltage will be dropped and you loose no current.

Jameco.com has the LM34, but you must specifiy the
LM34CZ(-40F to +230F) for $4.90 or the LM34DZ(+32F to +212F) for 1.99.
The 402 ohm resistor is a standard value for 1% resistors.

Russ, is correct. The Ph pin determines the polarity of the segment drive. I am using several of them to drive common anode displays. In each case the displays are multiplexed. I am using 560 ohm resistors in series with each segment. Driving the individual anodes with 2N3906 transistors from a 9V s...

I assume you are looking to monitor up to 100 degrees F and a little beyond. You could use the LM34 series of temperature sensors, they have an output of 10Mv per degree F. If you are willing to switch to Common anode displays you could use the ICL7107, set it up as a 0-2V DPM and you would be done.

No the 1054 does not require an inductor and it works from 3.5 to 15V. For a schematic see my
post on the poptronix website.

Cato,
You are right. I could post a circuit of a voltage pump with the LT1054CP. Since it is a 8pin
DIP the circuit still would be small. What do you think?

This is my solution to your problem. The first OP Amp inverts the voltage and divides it by 2.5. The second OP Amp inverts the voltage and adds the -1V offset. Adjust the pot for -1V output when the input is 0V. The schematic is at the following link:<p> www.poptronics.com/forums/electronic_bench/po...

You may want to check out this website, they may have a detector to sense body movements.
http://www.trifield.com

About three years ago I had a similar problem in that I wanted reading lights, but I wanted them to work from 12VDC. I had installed three large solar panels to charge my 12V 450AH batteries. The battery bank is used to run my amateur radio equipment. Early on I discovered that the batteries were ch...

Velleman makes a kit that will control the brightness of a lamp with a DC voltage of from 0-10 volts. The P/N is K8003. Jameco Electronics, WWW.Jameco.com has them in stock for about $22.00. I have used it, and was able to use a slow speed triangle waveform to do artificial sunrise and artificial su...

Something else to note is that the voltage drop for a specific current will vary between diodes also. This is important as if per chance one has to parallel diodes to increase the current capabilites of the circuit the diodes need to be matched, otherwise one or more diodes will carry more of the cu...

Metal Oxide Varistors are transient voltage suppressors having a non-linear current-voltage characteristic which sustains an almost constant voltage over a wide range of current. They are ideally suited to the transient voltage protection application and their high clamping efficiency and low steady...

I would suggest using a wall wart to supply power to a 555 as a oscillator at about 50 to 60 Hz followed by a CD4060 binary divider. The output of the divider to drive a triac optocoupler like a MOC3010 and then a triac to drive the lamp.

Chris is right it is called a Shader Ring. When I did the first post I was going from memory. I went to my source, which is a Potter & Brumfield Technical Data book(SA65 printed 9-86) From page 13,"In order to operate a relay from A.C., relay manufacturers use a device known as a shader rin...