Something to consider when shopping for these sorts of items is isolation. An autotransformer has one side common to input and output therefore there is no isolation and one side of you DUT will be connected directly to Mains. Connect your earth grounded DRO ground to the hot chassis and .... arc/flash
. So certainly from the repair side of things (where I came from many years ago), an a/t is normally used in conjunction with an isolation transformer so your DUT is fully isolated from mains. BTW, for those playing along, order doesn't matter: Mains->Iso->A/T->DUT or Mains->A/T->Iso->DUT. But of course, an isolation transformer is an additional cost if you don't own one. If this is the case, you may want to look at AC Power Supplies which usually (not always) have isolation transformers built in. Here in the states the B&K Precision 1655 and the Sencore PR57 were the 2 models you'd find in just about every TV repair shop back in the 70's and 80's. Only 3 or 4 amp output but how much do you really need? I was servicing huge 27" consoles that were still gas-state from the tuner to the tube and rarely did I have to break out the 10a Staco to power them. If you watch Fleabay you can pick up 1655's and PR57's in the $75 to $150 range and you get a 3-4a autotransformer, isolation transformer, and a large volt / amp meter. You also get uA leakage meter as an extra bonus (although the probes are often missing). Sencore also has an updated digital version of the PR57 which is the PR570, but they are still bringing $250+.
Another point to keep in mind is the output voltage range. Many a/t have at least 1 additional tap that will allow an extra 10-20 volts on the output. The ability to run at higher voltages is useful for all sorts of things making it a very desirable feature. Some include the ability to switch between the taps, others are hard wired to one or the other. I think my good old Staco is switchable between 120 and 140 vac out while the B&K was hard wired to the 140vac tap. Personally, I always install a switch and keep them in 120v to reduce the chances of accidentally powering something at full over-voltage.
If you do require higher currents then it's down to separate components. The a/t you list is the typical Chinese ones all over e-bay. I have no direct experience with any of these but they will follow the same rules as everything else. I'm sure it will work OK when you get it, at least in the nominal parts of it's curve. If you try to push it hard you will likely start discovering weaknesses in it's design. And of course you'll never find any replacement parts (with a/t's that normally means the wiper brush).
Apologies in advance for any duplicated material covered in replies that happened while typing this for the past 2 hours (constant interruptions).
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