[NostalgiaRadioTime]

Oh boy.

I seem to have a knack for finding majorly "modified" sets. So I'm hoping some of the phine phorum members who are a lot more knowledgeable on un-modifiying other's ideas back to schematic correct can give me some much needed guidance. Perhaps my savior on many occasions previously, Terry, can have a look.

First here is the schematic:
http://www.nostalgiaair.org/Resources/435/M0011435.htm

I'll start with an "easy" question....the tuning knob does not move the tuning capacitor or the movie dial drum manually. It's froze. There is an electric motor for tuning and I'm wondering if the set needs to be under power and the motor running for the tuning mechanism to function, either manually or with electrical assist?

Now the fun part...someone was trying to convert this to some type of push-pull configuration and added two extra speakers and an extra audio output transformer. AND...added an extra tube! A 6SC7...

1.) A 6L6 was subbed for the 6F6. My tube substitution manual doesn't list a 6L6 as a substitute. Are they compatible?

2.) An extra RCA jack was added with two slide off/on switches attached to it. It says "TV or FM" and then below it "Phono". Now there already was a factory RCA jack for phono on the back of the chassis. Should this just be cut out and eliminated? :
   

3.) Here's the extra audio output transformer mounted on top of the chassis, top and bottom view. I assume this was added to power two extra speakers mounted below the main speaker?
   

   

4.) Here is the extra added 6SC7 tube top and bottom. This looks to be a total mess and how is the best way to eliminate this?
   

   

More to come....

[NostalgiaRadioTime]

Another view of the added tube:

   

And the speaker board with extra two speakers added:

   

   

Some acoustic tubes were added and the bottom of the cabinet was enclosed These can be easily eliminated but I just wanted to show to the extreme this old audiophile went to in his efforts to try to get more power and gain out of this set:

   

If anyone has restored a movie dial set with the electric tuning, please chime in. With so many "extras" added to this set would I be better off to try to just do a recap / resistor replace and try to bring it up on the variac to see what I have or just try to "un-butcher" it and make it factory correct again? These modifications were obviously done decades ago, judging by the use of cloth wire. Someone knew what they were doing, and what they were trying to accomplish. It must've been somewhat successful as the set was obviously used in that configuration.

[Radioroslyn]

So as it stands what is the tube line up??

[NostalgiaRadioTime]

Here's what's in there now, along with the 6SC7

   

[Radioroslyn]

I vote for removing the 6SC7 circuit. It's really poor placement putting it right next to the power transformer. The magnetic field generated by the transformer is bound to add some level of 60cy hum into the low level audio. Thought I saw a 6L6 plugged into the chassis? If so get rid of it too.

[Eliot Ness]

That's pretty interesting with all of the old modifications.  One radio I needed to return to stock in the past I printed off the schematic and used colored pencils to trace the wiring and components as I brought them back to normal.  In your case you might want to enlarge the schematic and just print off sections so it's easier to trace and follow.

I've only had one movie dial set and it did not have electric  tuning, but all of my other sets with electric tuning were able to be tuned manually, so I'd check for something binding...... hopefully there isn't warped pot metal causing it.

[gregb]

That 6SC7 tube was most likely added as a phono preamp. I have seen that tube used many times in this application and it makes sense with the addition of the switch and RCA jack, most likely a low level input in conjunction with a high level input or maybe the switch just isolates the radio from the phono. As Terry pointed out not the best mounting location and they are usually mounted on isolated tube sockets as well. If you don't need or want a phono input, remove it all.

Gregb

[WallaceRoger]

Wow, that's one heck of a hackup...

Those radios are beauties, though

http://www.radiomuseum.org/images/radio/...560181.jpg

[NostalgiaRadioTime]

Managed to get the pushbutton assembly off of the chassis to see what's binding and keeping the tuning knob from working. The tuning capacitor is free and turns by hand as does the movie dial. One of the maze of gears, or even the motor itself is the culprit. Will investigate more tomorrow night.

   

   

Does anyone know how to change the mazda bulb for the movie dial? How does it come out? Does that black tip come out with the bulb attached?

   

[NostalgiaRadioTime]

Just an update....by tracing out the entire schematic wire by wire and taking out what didn't belong and replacing what did with new caps and resistors, remarkably it came to life on the first try! Here's a pic of everything that was either removed altogether or what was replaced. The final assembly should take place over the weekend.

   

[NostalgiaRadioTime]

Well the 1937 Montgomery Ward Airline movie dial console radio is all back together and playing great! Thanks to everyone for their help. Much appreciated!
   

   

   

   

[klondike98]

[WallaceRoger]

I can't believe all the junk you pulled out of that thing. That's a beautiful radio, nice job!

[morzh]

Greg, nice job and nice radio.

[KCMike]

Beautiful radio! Great job on your restoration.