I have an old tube - a model C-5 that I inherited from my Dad. It was manufactured by the Peerless Radio Valve Corporation in Holland. It come in a beautiful Orange and Blue cardboard box and is packed in horse hair. The base is nickle coated and the bottom looks like bakelite. It has four 1/4 inch pins - all the same size and the glass has a tit on the top. I was told by an old timer that it is a 201A and that Peerless manufactured these under the C-5 designation and shipped them to North America to get around the patent laws in the early 1920's. Can anyone confirm this - I am afraid to test it.

Your best bet would be to assume the 201A designation, but carfully start appling voltage to the filiment at 0.5 volts and work your way up to the voltage of the 201A if it does not light assume a bad tube or a bad designation. Any non-american tube without a conversion chart can be tricky.
:I have an old tube - a model C-5 that I inherited from my Dad. It was manufactured by the Peerless Radio Valve Corporation in Holland. It come in a beautiful Orange and Blue cardboard box and is packed in horse hair. The base is nickle coated and the bottom looks like bakelite. It has four 1/4 inch pins - all the same size and the glass has a tit on the top. I was told by an old timer that it is a 201A and that Peerless manufactured these under the C-5 designation and shipped them to North America to get around the patent laws in the early 1920's. Can anyone confirm this - I am afraid to test it.