Vintage Magnavox - REDUX - Help?

[yardlad]

Hey Everyone,
I have a 1950's Magnavox 477P (I think) entertainment console - TV, radio, turntable.
My mom told me it died before JFK due to a lightning strike near her parents' house.


I pulled the chassis out and cleaned it up a bit..



There are a lot of different tubes. The only ones that I recognize are the two 6L6s.
Then there are these listed on the chassis:
5U4
6AL5,
6AU6
6BA6 (x3)
6AV6
6BE6
6SN7GT

The chassis contains plugs for each of the accessories.

The speaker, phono motor, phono electronics, and TV are all powered off this rig.


This is what I'm working with.. (front of device is to the top)

Aside from seeing what appear to be wet caps, I'm not sure where to start.
What can I do to customize this?
I play guitar in a band.
My grandfather was a professional drummer.
I'd like to use this with my rig.

The DVM shows shows power-in works - but I'm uneasy checking the path

I'd hope the transformer is not shot.

any ideas?

 

[dcgillespie]

The power transformer is likely just fine. Your biggest problem is that unless you have the speaker, you're missing an output transformer. Back in the day, some manufacturers mounted that on the speaker -- particularly if it was an electromagnet speaker. Often too, if it was an electromagnet speaker, the electromagnet coil doubled as a choke in the power supply as well. Therefore, first order of business is to get, find, or obtain the original speaker before applying power to the unit. It will surely not operate with out it.

Dave

 

[yardlad]

I'm in luck!

I have the console in all its glory.

I can plug it in. Would the fried components be in the speaker, you think?

Thanks, Dave!

The power transformer is likely just fine. Your biggest problem is that unless you have the speaker, you're missing an output transformer. Back in the day, some manufacturers mounted that on the speaker -- particularly if it was an electromagnet speaker. Often too, if it was an electromagnet speaker, the electromagnet coil doubled as a choke in the power supply as well. Therefore, first order of business is to get, find, or obtain the original speaker before applying power to the unit. It will surely not operate with out it.

Dave

 

[gadget73]

Honestly I'd put it back together in the console, but thats me. Only a few of those tubes are actually in the audio circuit, and it doesn't have enough gain for a guitar. You can likely add an external preamp of some fashion to the phono or tv connection to make it work.

The wax dipped caps and the black stripey ones should be replaced, so should the can capacitor. If it possibly suffered a lightning strike, I'd probably start by powering it with the tubes out on a dim bulb tester just to see if the trafo is shorted or open. If the light doesn't come on, the transformer isn't shorted. If you have a variac, set it to 12v output and see if the various windings output about 1/10 of what the schematic shows. If it does, all is happy. If not, by some lucky coincidence I think I have that same chassis sitting around that I haven't gotten around to stripping yet, so let me know if you might need it.

You may need to change the caps right across the power line too. They look a little suspect, and I've seen those exploded after a lightning strike. One amp I was given had suffered that, and the only thing really wrong were those caps. Didn't find it until I plugged it in and saw a blue fireball underneath.

add a fuse too, old stuff without fuses make me nervous