I checked the voltage in a few of the outlets in the house. Some were at 118 V and others (including the outlet that was shorted out) were at 125V. Could this be an indicator that the loads are not balanced in the service box and could that have influenced the thing with the lights?

That's actually the only thing I could think of. Do you think it could also be the result of faulty wiring or bad components in the household wiring? My Grandpa did the wiring about 20 or 30 years ago and there are a lot of fluky things that he did such as having two items like a plug and light switch wired to two different circuit breakers. Also maybe it could be the result of aging circuitry? This whole thing has pretty much stumped me.

I must have been tired and wasn't thinking at the time but I thought I'd try to make the GFCI that I had plugged into the wall trip by shorting out the connections. I know it was dumb and quite dangerous but I have one big question that came to mind, when it was shorted out the lights went brighter. According to the theory that I have learned, the lights should have gotten dimmer because the voltage should have gone close to zero and the amperage should have reached the maximum level at the shorted point. I am just curious as to why and how the lights became brighter instead of dimmer and also why the circuit breaker didn't trip.

Is there a way to rectify the signal then put it through the transformer and use a less complex circuit? I don't mind skipping on the switching feature if it won't hurt the transformer or circuit. All I really need is for the transformer to step down the voltage to a workable level but I don't want to burn something up in an effort to make it simple ether.

Hey, I am trying to make a variable power supply and found that transformers are hard to find in working order when salvaging them. I finally found one that I think will work but the circuit that it was in was complex and even seemed to rectify the signal before sending it through the primary winding which I thought was weird. The transformer seems to be purely the windings and I don't want to blow it up when I plug it into the wall. The battery charger it came from stepped the voltage down to about 5V and I think it might have been regulated but I need to check the parts to confirm this. If I could get a higher output that would be great and I don't need it to be regulated for the purposes I am going to use the power supply for. Is there a circuit I can use to get the transformer to work properly?

I ended up buying a $5 iron from Walmart instead. I hope it will last at least a year and serve me well (despite the price.) Thanks for your input.

The size was too big but as I later found out, the wattage was too high as well. (40 watts)

I have been looking for a solder tip but after buying one at radio shack then returning it because it was too big, stopping at two stores and calling a third one I have not found one that works. I would prefer to not pay a large shipping fee, one or two dollars at most but free shipping would be much preferred. I have a Weller SP23 and it's 23 watt (it also has another number on it that says 336B.) Does anyone have any recommendations on retailers?

Is there any way to get the circuit to delay without the transistor? In the simulation I noticed that it would turn the LED on for a certain amount of time then the circuit would turn off when the chip timed out which is the opposite effect that I wanted.

I was trying to use LTSpice to design a circuit and it showed a spike at the transistor which was way above the power rating that I needed to accomplish. I added resistors at the base and the collector to try and limit this spike and ran another simulation of the wattage at the transistor and there was still a spike of several watts. Is this something to be concerned about or could it be a glitch in the program? Is there something I can do to prevent this?

I just looked at the simulation again on the aspect of the current and noticed that the current is a simple square wave and it dips down into the negatives every so often. The voltage is normal from what I an see. Is this a common glitch with LTSpice?

After reading some of the other threads I have compared the responses with the experience that I have had in my use of this site and I have not had much trouble at all with it. In the posts I have posted and viewed I have not seen any spam and I have not had any trouble with a virus threat otherwise I would not be at this site. I just wanted to say good job with keeping up with the site to all the moderators and thank you for all that you do!

This really is cool. I am constantly amazed how far technology has come.

I want to download a spice simulation program but was wondering if anyone had any recommendations as to which they like to use. Also what are your thoughts on LTSpice? I have had someone recommend it but I would like to hear input from others on about it. Thanks.

Hey, I don't have a large variety of resistors so I have used what I have. I have a 10 ohm, 20 ohm, 33 ohm, 1 Kohm and a 10 Kohm. Is this a good starting point? How close should the resistor value be to the value stated in a schematic?