T&L Publications

I had thought about building something similar for a different application. A mirror that would always reflect the sunlight to a specific point. Never built it (yet) but this is how I envisioned it working. Build a stand for the mirror that can pivot up/down and right/left. Next to it, build a stand...

There are voltage boosting units designed for use with amateur radio SSB transceivers. These radios generally transmit with 100 watts as long has you have the engine running and the radio is supplied with 13.5v or more from the alternator. The power output drops dramatically when running from the ba...

Hacklesup (and others for purposes of edification), A change in NEC 2011 (Article 210.4 ) ruins the 3 wire system of two circuits ("multi-wire branch circuit") as it now requires a means to simultaneously disconnect all ungrounded (aka Hot) wires. This either means that the two breakers ha...

Thanks for the comments! I can see that liability is going to be my biggest problem. Insurance would likely be expensive considering the insurance company has no way to know what my skills are and would have to assume that I could screw up or cut corners and create a hazardous situation. I guess I h...

In brief: Very expensive piece of equipment which has a "control module" that fails every 10 years (give or take. the life of the product is probably expected to be 30 years or more). The control module simply turns a few things on and off and has a couple of delay timers to operate things...

You can test the capacitor to determine its capacitance. You need: 1. The capacitor (of course!) 2. A low voltage AC source (you could use 120vac but I dont recommend it!) 3. A meter (or two meters) to measure AC volts and AC amps. The low voltage AC source can be simple transformer like a doorbell ...

The problem is most likely 12v coming out of the alternator on the lamp wire, thru the lamp, thru the relay coil to ground. When the alternator is not generating power (such as when you first start the engine), a small amount of current flows from the key, thru the lamp and into the alternator in an...

HELP! I was recently given what I thought was going to be a relatively quick project. It seemed so simple, PIC 16c71 with and LCD display module, a couple A/D inputs, buttons and a few outputs. Then I looked in digikey to get pricing and find (as I feared) they dont have them anymore, apparently the...

A friend of mine has several commercially built units. Thinks they are probably good as he has had one on a huge battery bank in his basement forever and the batteries still work. If you do some hunting around on the net you will find info and schematics to build your own much cheaper than you can b...

Dac, Assuming the batteries are identical, no problem in putting them in parallel, as you figured, it just gives you 12v @ 14AH, just pretend it is one large battery. No diode between the battery and the load. A fuse might be nice. If you were connecting a solar panel directly to the battery without...

Low flow showerheads would help, I'm sure. I don't know how high my daughter has the flow but this is a new shower installed about 5 years ago by a plumber, it probably has the flow restrictor. The other shower that my wife uses is fed by the old-style hot and cold knobs, normally opened about 1/4 t...

Thanks for the quick responses. I did the math, it will be cheaper to use the electricity. My gas supplier recently raised the "customer charge" to $13.50/mo, I pay this just to be a customer! The public service commission is going to force them to reduce it but then allow them to raise it...

Tired of being ripped off by my natural gas supplier, I have been thinking of replacing my gas-fired water with with an electric one. My cost for gas is high enough that electric will be cheaper! (Yes, I did the math) My current water (gas) is 40 gallon capacity with 34,000 btu input. It barely keep...

Not only do you not want to make either side of the line common to ground (or anything else), you dont want to place anything across the line that will show DC continuity as this will cause the line to be tied up. Any large capacitance across the line is also a problem. The isolation transformer is ...

I appreciate the comments, glad to know I'm not the only one who notices this.<p>I have noticed that some of my older NiMH cells that are rated 1200mAH don't self-discharge as quickly as the 2000's, must be something about how thin the chemical sandwich is or something.<p>Panasonic says not to trick...