[curlyroger]

I'm at my dad's this weekend and he's having me look at his old radio.  It is labelled as Philco 40-155.

It used to work years ago in our house but it hasn't worked since he moved to a retirement condo.  We plug it in, the lights come on, and we just get a lot of humming.  If I mess with the volume, I can get the hum to come and go but it's always there.  If I adjust the tuner, there is no audible change in anything -- all 3 bands behave the same way.  The only thing we can do is make it hum louder or quieter.  There is some crackling too as I mess with the knobs.  We've only ever gotten true "static" out of it once.  

I tried hooking up an extension cord (only copper we have) to the antenna screw with no change in behavior.

I know this isn't very helpful but just curious if there's any general tips or directions to explore would be greatly appreciated.

[morzh]

Roger

All I can tell you, uness you intend to do this radio yourself, step away, find a specialist and let him do it.
There is likely something like an open coil or a bad tube. A bad tube is easy but then you need spare ones to see if it is the cause and it ill cost you as you do not know which one to replace (OK, your rectifier and output are likely OK). An open coil is not something you should mess with unless you intend to get into the hobby and make it your first poject.

And...an old radio that has not been recapped, EVEN if it is working, is a ticking time bomb and should not be operated anyway.

See if there is an antique radio club in where you are, contact them, see if they can do it.

[curlyroger]

Thanks for the quick response. I was able to finally get a very faint AM radio station with the bass way up but there was tons and tons of noise/hum/feedback over the signal. I don't know what recapped means and I dislike time-bomb so I believe stepping away sounds like a good idea!

[klondike98]

Welcome to the Phorum!! Glad you stopped by. Recapped means replacing all the old electrolytic and paper capacitors. As morzh mentioned there are radio clubs throughout the US so you might find someone locally that could do the repairs. There is a list of repair resources located on this web site and some radio clubs listed about 2/3 down the page on this web page.

[Arran]

 Since the set used to play years ago before your father moved that's an indication that the tubes are more then likely still functional, it isn't too often that they will go bad from just sitting there. Capacitors and resistors, on the other hand, do go bad with age, or at least capacitors and resistors from the 1930s, 40s, and 50s, the resistors tend to drift upward in value, and the capacitors become leaky or open with age, the weak volume is a good indication that this has happened.
 There is one other reason why you should refrain from powering up this set until it has been gone through, and that is the rubber covered wiring that Philco, and some other makes, used in the period between 1939-42, the insulation can often deteriorate and cause short circuits to the chassis. Sometimes you can be lucky and find that it is still sound and plyable, other times it will literally crumble if you touch it, or become gooey and drip off the wires.
  One more thing, if you are thinking of restoring this set to keep as an heirloom or for nostalgia reasons it makes perfect sense, but these are among probably the least fruitful radios to restore and flip for a profit unless you are really good at working on them. That being said these Philcos are decent performers, and style wise they are not bad looking with a fairly good quality cabinets.
Regards
Arran