[Doug Houston]

Thanx, Arran. (and I think Ron, too).

The 6X5 issue is an interesting one. Zenith was the big offender (player), in the use of 6X5's in the rectifier duty. Our friends in Chicago had a nasty habit of bloating their tube counts, even a little. I'm sure that they considered it innocent enough to put two 6X5's in place of one 5Y3 (or 5Y4) in the rectifier sockets. I've never had a problem with having a 6X5 in an auto set. Zenith owners have had lots of trouble, though. I attribute that to the fact that the "Z" boys ran the 6X5's at higher plate voltages, and caused flashovers that happened lots less in automotive sets.
Go figure: There were loads of automotive sets that used 84 rectifiers. I never heard of ONE of them flashing over in a car set. And, quite a few of those auto sets were PHILCO!! And also remember that the 6X5 is simply an octal based 84! A 6X5 flashing over in a household set, meant curtains for the power transformer, and Zenith had no reputation for over specced power transformers

Back to the 37-650, I'm going to look into the accessibility of the rectifier socket.