Help on 1938 Emerson: Won't Turn On

[F. J.]

I have a 1938 Emerson BA-199, brown cabinet.
It worked wonderfully until recently, when it ceased to operate at all. I had transported it by car, and after the trip it was dead. Does anyone happen to know what might be wrong with it? As far as I know, everything is original save the capacitors, et al, which were replaced when I bought it.

Any help would be greatly appreciated.

 

[LizzieMaine]

Sounds like the ballast tube might have been jarred loose. It's the second one from the left in the back -- make sure it's firmly seated. Do you feel any heat in it when the set is turned on?

 

[F. J.]

Nope . . .

Sounds like the ballast tube might have been jarred loose. It's the second one from the left in the back -- make sure it's firmly seated. Do you feel any heat in it when the set is turned on?

Ms. McLeod,

I checked each one and pushed them as flush as possible.

There is no heat, "no nothing". The lightbulb doesn't even come on. It makes me wonder; I don't suppose a radio is analogous to a set of Christmas lights, and all it takes is that one bulb?

Do you think it could be a burnt-out tube? How can you tell?

 

[LizzieMaine]

Ms. McLeod,

I checked each one and pushed them as flush as possible.

There is no heat, "no nothing". The lightbulb doesn't even come on. It makes me wonder; I don't suppose a radio is analogous to a set of Christmas lights, and all it takes is that one bulb?

Do you think it could be a burnt-out tube? How can you tell?

That particular radio is a "series string" set -- the tube filaments are in series, just like Christmas tree lights. The tube filaments consume 62 volts, and the ballast tube, which is just a wire-wound resistor in a tube shell, and the dial lamp burn off the rest. Usually it's the ballast that goes bad rather than the regular tubes, and when this happens it cuts off all power to the set. If you've got a multimeter handy, you can check the filament pins of all the tubes and the ballast to make sure they're good.

You could also try checking the dial lamp to see if it's burned out -- that would also cause the set to fail. It's cheaper to replace a dial lamp than to replace a ballast.

This article will tell you everything to know about ballasts, and also shows you how to identify the type of dial lamp you have.

 

[F. J.]

Really?! It *could* be the lightbulb?!

That particular radio is a "series string" set -- the tube filaments are in series, just like Christmas tree lights.
[...]
You could also try checking the dial lamp to see if it's burned out -- that would also cause the set to fail. It's cheaper to replace a dial lamp than to replace a ballast. [...]

Ms. McLeod,

Goodness! I was just making a quick joke about Christmas lights, but you mean to tell me that I was right?!:eeek:

Thank you very much! I must say that I am quite honoured to have the help of a such a knowledgeable lady. It is always a delight to read your posts here on the Lounge.

I'll check the lightbulb and let you know if that was it.



On a side note, when the set was working, there was a gap below the dial and the lamp wouldn't illuminate it very well. Is there a particular "radio" way to direct the light?

 

[F. J.]

Well, at least it's not the lamp . . .

Alright, I checked the bulb and it looks good. The ballast tube is a different story, however.

I can't see inside it because of the carbon, but it's not supposed to rattle when you shake it, is it? I wouldn't think so.

 

[F. J.]

Where do you get one?

I've concluded that it is the ballast tube that needs replacing, but where do you find one?

The one that's in it is a L55BG, which I understand to be no functionally different from a L55B. However, I've searched all over the Internet and can't seem to find a company that has any.

Does anyone happen to know where to find a L55B Ballast Tube?

 

[plain old dave]

Check with your local Amateur Radio club. A LOT of hams keep obscure parts, and vendors at Hamfests have been known to have them too.

 

[F. J.]

Well, I was finally able to find a "new" ballast tube. It should be coming in any day now.

 

[F. J.]

Well, I put the new tube in and . . .

[video=youtube;QuoKNZjr8_U]http://www.youtube.com/watch?v=QuoKNZjr8_U[/video]