Step down transformer

I saw a tutorial where a transformer was used to step down voltage from 110 vac to less than 10 vac...I'd like to get one to play with my oscilloscope and component testing but I can't seem to find any online. I've look in Ebay, Amazon and thru google. I think I must be searching using the wrong terminology maybe.

I'd appreciate it if anyone has any ideas where I might find one.

Thanks.

They are everywhere. Salvage one from a small plug-in LED bedside clock, or other small plug in electronic appliance at a thrift store. You can get "doorbell transformers" (usually about 10V AC) at any home/building supply store, too.

The old style, heavy "wall warts" have step-down transformers in them too. There are buckets of those at thrift stores. Look for AC output, or take apart a DC wall wart and remove the diode and capacitor.

[u]Jameco[/u] has a good selection. (The first transformer on that page is not an AC power transformer.)

...Anyplace that sells electronic parts (resistors, capacitors, ICs, etc,).

Radioshack and Frys both have 'em. Maybe just search for “transformer” without the “step down” part. But be prepared - most of the search will be robots in disguise!

jremington: They are everywhere. Salvage one from a small plug-in LED bedside clock, or other small plug in electronic appliance at a thrift store. You can get "doorbell transformers" (usually about 10V AC) at any home/building supply store, too.

The old style, heavy "wall warts" have step-down transformers in them too. There are buckets of those at thrift stores. Look for AC output, or take apart a DC wall wart and remove the diode and capacitor.

FYI, doorbell transformers are loosely coupled ("soft"). They are designed so the current is limited, so in the case that there is a short circuit, it won't be a fire hazard. Honestly, I can't remember the details, but I believe it makes it a poor choice for electronics since the voltage can droop a lot under load. All transformers do it, but I think they do it more.

aarg: FYI, doorbell transformers are loosely coupled ("soft"). They are designed so the current is limited, so in the case that there is a short circuit, it won't be a fire hazard.

"Choke transformers." That is often - but I suspect not always - correct for bell trsnsformers.

For the purpose cited, to examine the waveform, and use as a curve tracer, that is just perfect. And the current limiting is reactive rather than resistive, which means that it the voltage droop is less than that due merely to winding resistance. So if your circuit only loads it lightly, it will be just fine.

Paul__B: "Choke transformers." That is often - but I suspect not always - correct for bell trsnsformers.

For the purpose cited, to examine the waveform, and use as a curve tracer, that is just perfect. And the current limiting is reactive rather than resistive, which means that it the voltage droop is less than that due merely to winding resistance. So if your circuit only loads it lightly, it will be just fine.

Sure. After all, it has to ring a bell, which draws a fair amount of current.

"Choke transformers."

Ah, that rings a bell.

120vac/10vac stepdown transformer