[Sean]

Ben,

Here is a photo of the underside of the chassis of a 41-608 I restored a few years ago. The white and green wires in the lower left corner of the photo would be the power wires for the phono motor. You can see how they are connected to the bakelite block cap.

   

[BenWA]

I am having a headache trying to understand this... I am trying to figure out the schematics vs the real world.

[BenWA]

Okay..... take a look at this. I like to colorize and mark schematics... I guess that's a newbie way of doing it but that's what I am... a newbie!

On the left side is the original schematic, with color and +/- added for clarification.

On the right side was done using the original schematic and a picture of the block. I made it a bit more complex since I was demonstrating having it hooked up to the block, which the schematic doesn't exactly do. The schematic just shows the nitty-gritty of how things should be connected to each other, not a block with multiple points where you can solder on wires.

Does the right side appear to match up to the left side in terms of how the wiring should go?

[Image: http://img.photobucket.com/albums/v222/i...g~original]


Also, my block still has the black tar. I just checked it today.

I will have to go about doing this: (pics from Google)
[Image: http://farm9.staticflickr.com/8027/71689...27c3_z.jpg]
[Image: http://mcclellans.com/images/Philco90/Bl...Inside.jpg]


Is your AC cable wired up for the white stripe side to be positive or negative? I see what appears to be a glass fuse holder wired up in-line to the non-stripe AC wire coming in, which in my mind would be the negative wire. Is that how you have it done, or am I seeing things? The fuse would presumably be on the positive AC wire coming in.

My diagram, the way I drew it up, seems to shows the connections to the block opposite from the way yours is, but it doesn't matter actually which way you do it. It comes out the same either way.

My diagram shows + on the connections furthest from the mounting bolt and - on the middle one. Meanwhile, yours has the - on the furthest from the mounting bolt and + on the middle one. (The one closest to the bolt, the chassis ground, is unused on the outside)

[sam]

ben
looks right but should had used safety caps in block (nice job cleaning it out ) but you are adding fuse ? so it will be ok
keep it up and will be working again

[BenWA]

Like I said, I haven't actually DONE the block fix yet.. those are pictures I found on GOOGLE.

Yes, I wish to add a fuse.

[Sean]

Ben,

When you are talking about AC there is no positive wire and no negative wire. There is the Hot wire and the Neutral wire (the Hot wire can be both positive and negative at times because it is alternating current). I replaced the original power cord with a polarized power cord (a 6' extension cord with the outlet end cut off). This will ensure that the plug is always plugged into an outlet the same way so that the same wire is always connected to the Hot side of the line (as long as the outlet was wired properly). The Hot wire is connected through the fuse to the power switch. The Neutral wire is connected to the lug on the block that is furthest away from the ground terminal. You would need to check if your plug is a polarized type if you want to wire it the same as mine. I would consider the white striped wire to be the neutral wire.

The way you have your diagram makes sense. You are correct that it may not be wired on the same side of the lugs as mine but electrically they are the same.

When I restuff bakelite block caps, I use a heat gun to soften the tar inside. I made a small tool with a dowel rod and some scrap brazing rod (you could use a piece of brass or copper rod also) that is small enough in diameter to fit inside the rivets where the capacitor leads come through to connect to the terminals. I clip or unsolder the capacitor leads from the terminals, heat the capacitor body until the tar softens, then use the tool to push the guts of the capacitor out the back side through the rivets. Do this over a trash can and the guts are easily disposed of. This leaves a pretty clean pocket pocket inside for you to install your new caps. I used to chip the tar out but found it makes more of a mess, takes longer, and there is a risk of cracking the outside of the bakelite block.

[BenWA]

I'm sorry, hot/neg is what I meant. As you might have guessed, I have mostly worked with DC power (12V) so I was mixing up the terms. So is my "positive" on the diagram basically equal to "hot"?

Mine has what appears to be a newer, cloth covered reproduction AC cable with a non-polarized reproduction plug end. The cable is in too good condition to be the original. Same with the plug end. Since both items can be readily purchased online, I suspect they are modern.

I also suspect the radio restoration was done in the past 5-10 years. They just had no clue what the heck to do for the record player it seems and started playing guessing games.. then gave up. Maybe someone was being paid to do the work and the customer decided they put enough money into it and told the restorer to quit at having the radio working.

Oh... and are the caps in the block 0.01 uf, correct? The writing is hard to make out on the schematic.

Wading through various capacitors... what would technically be "correct". I found one saying 250V max was only for DC, with 125V AC being the max. Assuming my AC power from the wall stays below 125V, I'd be ok. But what about getting a larger voltage max cap just for safety? What would be the next step up.. without a large price jump?

[BenWA]

Here is a shot of the underside of the bakelite block right now. It's not potted. Could it be somebody put some kind of black stuff back in? It's not soft, however. A pencil tip or fingernail cannot make a mark. One video I saw on youtube showed one of these with a potted end. Maybe the bottom is just gone due to the tar expanding and the bottom was thrown out by the person who did the partial restoration.

[Sean]

That is tar that you see. These didn't have a cover over them, just filled up with the tar. They would originally be 0.01uF paper capacitors but since they are across the power line they really should be replaced with some AC Line rated capacitors. I use Vishay 0.0047uF XY capacitors in this application in all the radios I restore. You could use the 0.01uF version but they are more than twice the price and I doubt you will notice a difference.

Vishay 440LD47-R at Mouser

Actually this radio would not have had a cloth power cord on it originally. Philco stopped using cloth cords well before 1941 so the one on it was put on by someone else. Doesn't mean you can't use it though.

[BenWA]

Thanks for the suggestion and information. Some of the smaller gauge wire within the radio IS cloth covered and is obviously original by how rotten it is... especially the speaker wires.

The people I bought it from texted me the other night and said they found a knob in the driveway... the one to the record cutter's switch! I went by and got it today.

[BenWA]

EDIT: I left the post intact, but I found this which voided what I was saying:
http://www.justradios.com/safetytips.html

There really is so much to learn!

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@Sean

I found 0.01uF at Radio Shack for $2.50 for 2:

https://www.radioshack.com/product/index...Id=2062363

I wonder if they are any good? The 4700pF ones you linked run $2.50 for two, plus $4.99 shipping, which triples the cost.

Seeing as how those are the only two caps I need for this partially restored project, I don't have anything else I need to order from Mouser.

I need speaker wire but that's universal and cheap from anywhere they sells it.

I did notice the Mouser ones are labeled as "safety" ceramic caps. What is "safety" about them, or is that just a useless word they added to the product description?