At first you wonder how they got the difficult part correct and screwed up the easy part. The parts that fall apart aren't really necessary so...

At first you wonder how they got the difficult part correct and screwed up the easy part. The parts that fall apart aren't really necessary so you can still use the thing. Often it is better stripped of the unnecessary junk. So why are only the frivolous extras breaking? This is easy to explain. They put the bright people on the essential difficult part and the less competent people o...

Best to ask here or ? My gas furnace is a Holly. It has an old mercury two wire thermostat. I want to change the thermostat so that I can...

Best to ask here or ? My gas furnace is a Holly. It has an old mercury two wire thermostat. I want to change the thermostat so that I can set the same two temperature ranges, day / night, for every day. I do not understand thermostats. The local store does not know how to advise me. Thermostat suggestions please and maybe a little tutorial.

This must be a really really common problem and the only reason it is diffi= cult to find on youtube is the wrong search terms: If a device...

This must be a really really common problem and the only reason it is diffi= cult to find on youtube is the wrong search terms: If a device has a power on button latch switch and you want it to turn on a= nd off like a light bulb, i. e., when the power supply is plugged in or a r= elay connects the power, or for solar, when the sun comes up, is it a commo= n solution to run a wire from th...

I can put a resistor after a voltage that's too high for the circuit? Of course the resistor must handle the current. A decoupling capacitor...

I can put a resistor after a voltage that's too high for the circuit? Of course the resistor must handle the current. A decoupling capacitor after the resistor. Any problems with that? Thanks.

I am running 3 phase AC into a set of transformers, Y config, and thence into bridge rectifiers . One leg of the output side of the transformers...

I am running 3 phase AC into a set of transformers, Y config, and thence into bridge rectifiers . One leg of the output side of the transformers goes to the diodes. the other leg to the Y connection. That Y connection gets warm. (why?) Should it be connected to DC ground?

I need a sanity check - I think I understand, but there's doubt. If I rectify AC with a bridge and use the full-wave output to power a DC...

I need a sanity check - I think I understand, but there's doubt. If I rectify AC with a bridge and use the full-wave output to power a DC motor, it's not the same as using "pure" DC. There is an AC component to the full wave. (The motor is a brushed PM if it matters.) If I take the Fourier series of the 1/2-sinusoid and consider each component separately & then superimpose them, I sh...

I don't want to have to be there to turn on the cam. Instead it needs to be turned on by a relay. If necessary I will invade the flip flop on...

I don't want to have to be there to turn on the cam. Instead it needs to be turned on by a relay. If necessary I will invade the flip flop on off switch but I'm pretty sure they have figgered out a better way. Bret Cahill

The sealed-up-in-plastic power supply comes with the plug, 110v U.S. or 220= v EU. On a 110 v AC U. S. plug the output appears to be 110 v DC...

The sealed-up-in-plastic power supply comes with the plug, 110v U.S. or 220= v EU. On a 110 v AC U. S. plug the output appears to be 110 v DC and 220 AC on a = volt meter. The LED part of the rope light plugs into the output of the power supply. = It looks like two rails go the length of the LED section which can be cut e= very meter at a marked location. Some LEDs can burn out while t...

Working on a gadget that uses a 12 volt motor (10 amp peak) and misc electr= onics running on lower voltages. It is powered from an external PSU...

Working on a gadget that uses a 12 volt motor (10 amp peak) and misc electr= onics running on lower voltages. It is powered from an external PSU like a= laptop supply, but 12 volts. There is also a sealed lead acid battery for= backup when the power fails. =20 This design uses pairs of pFETs to route the power from the 12 volts input = when present, or the battery when the line is not p...

I built an alarm circuit from a book I bought called Make Electronics by Charles...

I built an alarm circuit from a book I bought called Make Electronics by Charles Platt. https://drive.google.com/file/d/1NxvKdZCqykuSjBvPVoWz_MEMhKYMMz9E/view?usp=sharing The said circuit produces a siren type sound on a buzzer so I added an led through a resistor, a 10k pot and a LDR. I then connected the centre pin of the 10k pot to pin 2 on the top IC555 shown on the schematic ...