A few years ago I moved, and I finally got around to unpacking old boxes and throwing out a lot of unused stuff. I came across this “Advanced American Telephone Model 972” also call the AT&T 972. It’s a decent 2-line, caller ID telephone. Of course I had no idea where the power supply was. I looked all over the phone and couldn’t find that little diagram that shows you the the polarity of the power jack and voltage and wattage. I searched for, found, and downloaded the instruction manual. Would you believe that in 29 pages, not once did they describe the power supply capacity and details? The manual said to call some 800 number for replacement parts. I’m sorry, but that’s bulls**t. So I hit google, and there were tons of places offering to sell a power supply specifically for this phone (eBay, Amazon, and on and on.)
Here’s the catch: EVERY SINGLE IMAGE was deliberately obfuscated so you couldn’t see what the voltage was. I probably have it in a bin full of wall-warts, and just don’t know which one it is because the manual won’t tell me and everyone selling a replacement part would rather sell me something for $25 than just say hey, here are the specs, check your stash before spending money.
Well, I figured it out, and so I’m making this blog post to undermine this nonsense.
It’s a 9 Volt AC, 300mA adapter. Yeah, AC. Not DC. Weird. After searching for at least an hour, I found an expired eBay auction with a decent photo (shamelessly screen grabbed here.) Turns out I had one adapter with an AC output, it was 9V / 200mA, and it worked just fine. So there. To hell with all you vendors who deliberately obfuscate the details of the power supply in an attempt to make people spend money.
In conclusion: if you have an AT&T 972 and you’re wondering what the power supply voltage and amperage should be, the phone takes an AC, 9V, 200-300mA supply.