[Eliot Ness]

The D5 spray is 5%

[radiohenry]

Mike and Paul,
       Thanks for the reply.I am going to You Do It  this week. I didn't know you could still but the regular non adjustable spray can.
                                             Henry

[morzh]

So there is some effect from Deoxit: BC key works every time now. Ok, I'll take that.
Cleaned the cabinet with GoJo.
Maybe will attemp to put the chassis inside the cabinet tomorrow to see how it plays and if the howling goes away.

[morzh]

But. When I attempted to put in an antenna and the reception got louder, I saw smoke. Not sure where it came from - not from the same place as before. I turned it off. Then on again, without antenna - works fine, no smoke. This is a weird acting radio.

[morzh]

I took the cover off the equalizer regulators: interesting construction. There were tons of dust in it.
So I vacuumed it furst.
Then I saw that the thumbwheels rotate the wipers of potentiometers that are open type: the resistive element is just a piece out in the open and the wiper is also in the open. No encasing at all. Very easy to introduce Deoxit. Which I did.

The High regulator uses Bowden cable. It's that same cable used in bicycle braking. And it seems it does not move as much as it needs to. But then the travel is limited by the fixture that holds the rod which is the IF core (or so I think) and it has factory paint on it.

The howling takes place when the lowest equalizer regulator is at the maximum. Wonder why......

Oh....with two small pieces of wire got reception on UKW (FM). Very quiet, but several station. Maybe with the real antenna plugged in it wil get better.

[morzh]

I just bought Sams Photofact.
After I bought it, I realized the US version uses a tad different circuitry, like 1/2 ECC81 instead of EC92.
I hope I bought the US version, as I did not know it was different and so did not ask (not a big deal, but....).

[morzh]

The Photofact came today.
Yes, it is the American model.
The sch explains a few questions I had after using the German sch - it is quite different. Also much more clear the way it is drawn.
And it has the pictures and drawings, and alignment.
And it is original and clean and readable.
And! It is in English.

Many, many plusses.

[morzh]

If someone has the owners manual for one of these, in electronic form, I could use it.
Without it I have to figured out how to operate this radio all by myself and it is a hi-end, so there are, well, features.....

[morzh]

Well, I did make another short when I recapped. This is the second; the first one was, as I wrote before, when I shorted out 8uF cap. That is.....the radio relies on the formed leads not to bend and touch stuff, but they do bend and touch. That resulted in 10K (the first RC after 600 ohm main filter resistor) smoking.

This time it is along this same filter, only this was a solder short. The two pins of the switch used as solder posts, one is grounded and one is nearby. Happened to solder to it, shorting the 33K/33nF RC filter for the 1st AF amp (ECC81 second half) to GND. It is the point where 33nF, 33K and 22K tube's load resistor come together.

Funny thing it did work. Not sure how.....I guess the grid capacitively coupled into the plate.
Now that I fixed it, it sounds much better.
However the howling did not go away.
I found this short while tracing the feedback from the transformer secondary. Saw something that did not make sense.

Now I have to see if I did swap the plates. I doubt it, I checked and re-checked by the photos I made.

One more possibility is, if the full acoustic system is not plugged in, maybe that affects the frequency response.

I tried it once, but then I did have that boo-boo with shorted power to the AF Amp.

[morzh]

So I tried the acoustic system plugged today, now that I fixed the AF amp.
No, still howls. But sounds mighty nice when it doesn't.
Interesting it does it on BC band but barely does it on FM band.
And it sounds very good on FM.

So...need to break out the scope. See why it oscillates.
Also the sch has an omission: the Voice switch when switches to the Voice mode, also uses another pair of contacts to cut the Feedback signal from the output transformer by loading it with 2.2K resistor to GND. This resistor is not shown.

[morzh]

Well....I thought something was off when I reinstalled the transformer and soldered back the plates.

My photos were not very clear and the US version Sams Photofact has them backwards.

I re-examined my photos and decided there was a hint of the wrong plates hookup, that would turn Negative feedback to Positive.
So I swapped them and....it works fine now.

I am amazed at the sound through my small 4 ohm test speaker.


Now, clean the dial....install in the cabinet....go to the changer part.

[morzh]

Well, I was afraid of it.
When reading the Radiomuseum thread on this radio by Rudiger Walz, I learned the woofer's cone rippled outside part that connects to the basket rim, and which is made from some sort of foam, disintegrated and the cone was loose.
Today after I put everything back to the chassis, I put it in the cabinet and played it. I heard bad rumbling and I realized I probably have the same problem.
I disconnected the woofer and opened the cloth it is wrapped in.
I saw exactly what Rudiger and the other person who commented on his thread both described.


   
   

Not only that, but the soldering post that connects the wires and was riveted to the basket, cut through the rivet and was loose also.

   

So, the cone is in great shape, so I think sending the speaker to Dave in the Speaker Shop and asking him to supply it with a suitable rippled circle.
I think the soldering post could be just screwed with a small screw and a locking washer.

[Paul Philco322]

The saga continues......................

Bet you the thing is super duper when done.

Paul

[morzh]

I am sure it will be.
Judging the way it sounds on a mundane 6" speaker, it should sound marvelously when the speaker is fixed.
Meantime after I send out the speaker, I should start with the changer.

[morzh]

When I said "Dave", I mean Rich.
Sorry.

I called the Speakerworks who I was pointed by AJJ on ARF, they sell re-foaming kits. They have not come back to me yet and from talking to them I think they might not have what I am looking for.

So I called Rich and he said that he has a foam surround for 10" unit; it is wider than what I have but he would make it work.

And, considering that, if I were to send it to the oter shop to do, it would be $50 while Rich does it for $30 - the choice for me is well delineated.