[dtvmcdonald]

Well, the speaker really won't easily come out. So far no luck getting
a MHD4. Another guy found one on a web site, but untested and
no guarantee. I really don't like that, especially when a few lines later
in much larger type it says "Tested and 100% guaranteed".

If I could get a correct tube base (from a broken tube, for example)
I could attach it to the corresponding American tube, a 4AV6,
and try that out with a known good speaker. If that works I may just
stick a small 4 inch speaker behind the bad one to get it running.

I tried realigning with no luck: trying it wider resulted in overload in
the middle stages. Trying like the picture someone posted above
gave ringing. I then aligned it to the official specs for wide which still
gave ringing. Then I tried tweeking just the last stage for the best
transient response and that resulted in no ringing and some response at
2.5 MHz. A really good picture resulted.

I played with the push-about coil: its needed, there is no way the tube
could be coaxed to a useful position, and it really has only a modest
effect on focus. Using my monster permanent magnet for centering
resulted in the same defocus. And of course it really IS authentic.