[winkydink]

Before bidding for a variac or isolation transformer on eBay, visit some electronics swap meets or amateur radio shows. They turn up very frequently and since they are pretty heavy items, you won't have to pay a fortune on shipping (it's also a good place to find old radios, parts & test equipment). Last year I picked up a massive antique variac for $20 at a local hamfest. Look for one that can handle a current load of at least 2-3 amps, which is plenty for most radios, although radios with high tube counts may require something a bit beefier.

An isolation transformer isn't a requirement for working on radios, but it's a lot safer if you use one. Think of them as an inexpesive insurance policy. Look for one that has a 120 volt output and an adequate current supply.

.....
Dave

Unfortunately I am several hours from the closest major city, so ebay or retail are my two best choices. That is unless someone from the forum has a cache of variac and/or isolation transformers that they wish to sell.

Again, any brands to focus on or avoid ?

One other question, with regard to replacing the power cord for these type of radios (AA5). Should I purchase polarized or non polarized cord/plug. Is either "safer" ? I have read that because the original plugs were non-polarized, when the radio is plugged in one way vs the other that the chassie is more dangerous. Not sure if this is true but perhaps someone can shed some light on this for me.

Thanks.