[MrFixr55]

Sorry, Chas.

Re the burns, I broke my first TV at the age of 3.  Between my electrical experiments (My mom was convinced that I caused the great blackout of 1965) and other antics as a kid, the fact that I made it this far is proof of the existence of a benevolent Deity.

Technically, the variants in the language may be American variants, not British (However, reading through a Jaguar manual, years ago, I had to figure out what a bonnet and a boot is, as well as drop head vs fixed head.  I also learned quickly why Lucas was referred to as the Prince of Darkness.

+1 on the other comments on your radio.  Over here, 6A7s, 78s and 80s are very common and cheap on eBay.  Looks like that they put the EBC33 where the PenDD61 went, moved the socket for the rectifier and put the EL53 where the 80 was.  Looks like they subbed the 78 with a 6K7, another common tube, but they likely changed the socket instead of using an adaptor.  The EBC33 has the same pinouts as a 6Q7 or 6R7 but according to "Valve Museum", the 6R7 is the equivalent.  Therefore, this is a real Phranken-Philco, but not from the factory.

How you proceed depends on your goals.  Returning to the original configuration will return the radio to originality but the addition of that triode audio stage likely added better performance.  If you find the original output tube or the one with the 4V heater but want the increased performance of another stage of audio gain, consider putting a 7 pin miniature such as a 6C4 (if detector diodes are not needed) or 6AV6 (if using a 42 or similar output tube) under the chassis.  Another alternative is to replace the 6K7 with a 6F7 which contains a remote cutoff pentode similar to the 78 but has a triode that can be used as a 1st audio amp.  If you get a PenDD61 or equivalent, substituting the 6F7 for the 78 / 6K7 will give you the best of both worlds.  Since the 78 (or 6K7) is under a shield, the mod will not be visible in the assembled radio.  If you are forced to use an output tube without diodes, a solid state diode under a piece of heat shrink or "spaghetti" will solve that problem.

In the US, during the war, no new civilian radios were available.  RCA (and I think GE also) produced a substitution manual that reported direct substitutes or if no direct, the best substitute and what "mod" had to be done.

Hope all of this helps, and again, welcome to the Phorum and to this hobby!

BTW I like your tag.  I recycle my cars and tech products by fixing them and keeping them running. Our 3 cars are a 2000 Ford Explorer (95K miles), a 2003 Ford Taurus (145K miles) and a 1991 Ford Aerostar van (190K miles) (and this is in the rust belt northeast US.  All 3 cars have around town miles as opposed to highway miles.

Hope all of this helps!