Jameco ValueproTR4820-91-R Power Transformer, AC Wire Leads, 9W, 9 VCT, 1A, 115V/230V, 1.67" H x 1.82" L x 2.43" W

I used this transformer for the AC supply portion of a home-built Commodore 64 power supply, which it handles admirably. While a slightly better labeled wiring diagram would have been nice, it didn't take all that much fiddling with a multimeter to be sure which wires to use. (Nobody wants to fry vintage hardware because you hooked it up wrong without checking...)For those who want a confirmation - For 110v connect mains to black/white and then the computer side gets both blue wires - it's 9V across the full coil.While I haven't had it in operation all that long, I'd happily recommend this product.

As others have stated, it's missing specs. I've attached to this review. It seems ok quality, although its quite noisy.The secondary actually has three different possible outputs. The inner and outer tap on the secondary winding produce 9v. The center tap in 6v. The primary can be either 115v or 220v.

The Jameco Valuepro TR4820-91-R Power Transformer is a dependable choice for anyone working on low-power electronics projects. Its 9V center tap output and 1A current rating make it versatile for a range of applications, from powering small circuits to use in DIY power supplies. What stands out is the solid build quality—you can tell it's built to last, with sturdy AC wire leads and a compact form factor that fits easily into most enclosures.The dual voltage input (115V/230V) is a nice feature, giving flexibility for different power setups, and the 9W power rating is more than sufficient for most small electronics projects. At its size, it’s compact enough to work into tight spaces without any hassle.For the price, this transformer offers great value and performance. It’s reliable, easy to integrate, and perfect for hobbyists or anyone needing a straightforward power transformer solution. Highly recommended for DIY electronics!

Seems solid. Bought a couple for a few projects. The secondary has two blue wires and a (not quite) center-tapped black wire. Blue to blue is 9 volts. Blue to black is 6 volts, and the other blue to black is 3 volts. Dual voltage primary primary gets 120 volts across either black and white or red and white. 240v input across black and red. Also works as a step-up (probably with not much amperage) when using 120 volt input, found 240 volts between red and black. I was surprised by this, but my friends who know things were not.

This tranformer came is a box with no ratings marked off for input or output voltages or amperage, the transformer also has no identifiable numbers. The primary seems to be tapped for 120 or 240v operation however the secondary is not a 9v center tapped transformer, it has taps at 3 and 6 volts. By size it looks like a 500 to 1000 milliamp model. If you just need 9v it will be ok but if you require a center tapped 9v transformer , look elsewhere.

I refurbished a C64 power brick with this 9.6v on the two blue wiresused the red and white wires for 120v intapped off the back wires

Units are not marked for primary/secondary. All secondary wires are the same color. No UL Stamp. Not taking a chance- returned.

A Little confusing as to which leads are the primary and secondary.Read it out with a multimeter, works great! Primary is the higher ohm reading.