DISASSEMBLY and REPAIR: Philips Radio BX335U

Philips Radio BX335U from 1953

This is a PHILIPS valve\tube radio from around 1953. Tubes are the grandfathers of the transistors. They were hotter, consume more and their lifespan was shorter, but many people still prefer them to transistorized amplifiers as they sound better! These radios are really rare these days as many already end up in the trash or were forgot to rot in some moisty garage. This one is no exception, the owner was about to throw it away and that is when i stopped him from commiting such crime!
These old radios tend to have all sort of problems, being one of the comum one, the caps. These are always bad in these radios and you should never plug the radio into the mains if these caps are still around inside the radio. Replace them all and  test the radio afterwards, preferably with a 60 watts lamp in series with it. If the lamp glows strong initially and them dims, then the radio should be ok to be tested connected directly to the mains. If the lamp has a steaty strong glow..well then you have a short inside the radio.
Another comum problem are the tubes themselfes. These might be harder to find, although i was lucky with this particular radio. One of the rarest but worse problems you can get if a failed coil. I hope this never happens to me...

You would be amazed (or not) how much dust these devices can collect just be sitting around for a long time!

Top view of the dusty chassis

And here is the dusty valve radio chassis. They are a beauty. I'm sad i don't have any other tube radios in the house. My wife isn't :)

And these black cilindrical components are the failed capacitors. They HAVE to be all replaced!

Thank you internet for the schematics, without it i would be pretty much doomed because the value printing on the capacitors is mostly gone on each one of them!

This little fellow was already blown apart. And most of them were very fragile, turning in to tiny black shreds.

Two of the many capacitors removed. Notice the one with a huge crack on it. That's the condition most of them were in.

And here are the new capacitors in place. The two big electrolytic capacitors are the power filter capacitors. They are doing the job that the big can on the top side of the chassis was doing. I left it on just for cosmetic reasons!

And here is the chassis cleaned and working like a charm.

These tubes look great when glowing in the dark! Ok maybe there is a bit of over exposure but what gives? Looks astonishing.