NightFire Adjustable DC Power Supply Kit (#1725)

Not just for beginners, though. This kit is inexpensive and easy to build. I have built three to be used with a solar panel to power my Ham radio hand-held. They are great for the money.

Great kit for the money,easy construction,good board layout,worked fine from the beginning. Stable voltage regulation, I am very satisfied with this production !

Using it to control a six volt DC motor at variable speeds. It worked exactly as expected. With a heatsink, it will supply over one amp.

Do not hook up to 110-120 volts Also no pot for adjustment

These folks have good products

It is an adjustable PS however the included pot is rated at 10K Ohm's which means fine tuning is out. It has very course adjustments meaning a very slight turn changes the voltage by an entire volt. It is really difficult to get an exact voltage just down to the .1 variation like 3.5 or 4.5 are difficult to achieve. Also there is a 1.2 volt drop from source. This means if you want a 5Volt output than you need at least 6.2 volts coming in. I guess you get what you pay for!

Actually, a well-done little kit. Well made, and by following procedure, careful assembly, and careful soldering, a very nice regulated and variable power supply results. Why a small, 20 cent ($US) little "U" shaped or "star" heat sink was not included is unusual, as these LM317T based circuits almost universally mount a heat-sink to the LM317. Without the heat-sink, the circuit can provide up to 1 amp current to the unit being powered, and with a heat-sink, up to about 1.5 to nearly 2 amps absolute maximum.Suggest using an accurate DVM (digital volt meter) to monitor and set the voltage. There is no one power transformer voltage rating that will supply the entire approximate 1.5V to 30V or so output range, rather, the transformer selected provides a range of DC output. So, for example, a 12V AC transformer at the input will usually provide about 5 to 8 V DC range of adjustment, a 15V transformer will provide about 8 to 13V DC output range, etc. This range will vary a bit depending on the choice of resistor values included with the kit.

I didn't want to buy something for a buck and spend 5 bucks in shipping. So I ordered a ton of stuff from these guys just to see what the shipping would be and it was still $5. So I bought it all. I love the way the packed all the components in tiny zip lock bags and marked with the item and description. The only complaint I have is that these guys don't have every thing I need but may be they will start. Definitely recommend. But be sure to buy a bunch of stuff to justify the shipping charge.