[morzh]

Today feeling an itch to do something, I pulled the  chassis from my 41-280, which I bought about 3 years ago, in a very good condition, for, I think, $70 or 80.

Very clean chassis. Some dust. No dirt or rust. Two repairs, one is an electrolytic cap in parallel to the existing, and one is a black tubular black beauty cap, likely in place of a failed Philco one.
The output xfmr might be bad. The speaker is good. All but two buttons are good. The tenite (or whatever that is) bezel is good.

And....all the wires look not cracked and feel pliable. 

So, perhaps this weekend I'll attempt the recap.


PS. The output xfmr seems to be ok.
PPS. Boy did they use small power xfmr. I guess this is due to the low filament currents, at least in part.

[Arran]

Mike;
  I think these chassis used a pair of #41s for output tubes, so basically a 6K6 with an old style six pin base. The plate voltages are also not especially high, I believe its 180 volts max. But the small size may explain the failure rate of the output transformers in these things, I have a chassis from a Canadian version and someone replaced it with a Hammond one back in the 1950s or 60s.
Regards
Arran

[GarySP]

Mike, document this restoration closely.  I've got one of these as well, and I'd rather learn a little before I jump into it.  Take care, Gary

[morzh]

Arran, yes, the output xfmr is rather small.

Gary,
I'll do my best to document all I will have done, though not sure how much it will be, as the wiring, unless I ruin it, is likely to stay. Nowto the recap - and it ain't gonna be much different from the one I have just done on the Hippo. Disembowel - restuff, ptetty much like gefillte fish

Just realized I am almost out of 0.047 uF tubulars - spent a ton between the 38-690 and the Hippo. Maybe two are left.

[morzh]

So....

Same exact type of the electrolytic capacitors as before in Hippo is used here. Axial with the paper shell.
The ends are potted with very hard and brittle compound. In Hippo's cap it was crumbling a bit easier, but is not really re-usable as it mostly creates powder and rarely falls out in chunks.

The first cap (12uF) took me little time to gut, the second, however, proved intransigent and it took me good 20 minutes to pick out the deeply potted end (one end is always potted deep, and another - shallow). The other end was very shallowly potted and I cleaned it in 3-4 minutes.

I use small chisel.
   

You have to pick all the way to the end of the cartridge.
   
   

Then the cartridge comes out without much effort and with no heat applied.
Note that I tried use heat on that type cap in the Hippo - no. Did not work. Could it? Possibly. I got too frustrated to find out.
   

I used two 22uF caps in series. Again, these are Panasonic 450mA rated caps, the highest I found at this capacitance. I need 12uF and so two will give me 11uF which is acceptable, rated at 450mA ripple which is, again, acceptable.

   

[morzh]

These caps, back to back, are exactly the size of the shell so I had to improvise to pot the cap while creating some cover for the caps' end from some thick paper.
I still have not bought the brown hot glue, and there is no place to melt some tar on top of it, so this will have to do.

   

The next cap is 16uF and 8uF; I decided to use the same 22uF high ripple cap simply because this value is next one up I have and is acceptable as it is after the field coil and so higher capacitance is allowed, plus it will help with filtering. 12uF, in the place where it is (filtering a resistive divider) and even higher value is also fine.

   

Some pics of the chassis
   
   
   

[morzh]

And the back
   

[morzh]

I finished the recap today. To be truthful, this is one of the easiest ones yet, the tubulars being 10 of them, and the assembly not being crowded. There was one backelite block for line filtering, abd, sure enough, the eyelets were flooded, but since it was just one, it didn't take long.

I also changed a few resistors, and maybe will change a bit more, and hopefully tomorrow I could try power-up.
After checking the tubes of course.

[GarySP]

Nice work, Mike.  did your set come with the long wire antenna adapter?  Mine didn't.  I know there is a schematic in the phorum for building one, but I'd like to find an original if I can.  Seem to be scarce as chicken teeth!  Take care, Gary

[morzh]

Gary

AFAIK no, no adapter. I have internal antenna. Judging by my Zenith Spinet, it works well even in basements.

[morzh]

So I quickly checked the power xfmr without the 84 tube, then just took the speaker out of the cabinet and powered it up.
Of course I forgot that the right button has to be drpressed and for a minute or so tried to tune into something, until I pushed it and the "Classic Gas" from our Jersey Shore 1160am poured in.

The band switch needs cleaning, and I ordered some red Deoxit (obviously my Green doesn't do squat to old oxidized contacts), the volume pot is scratchy as a siamese cat. The tuning cap could use some cleaning, though I think I'll just use the can of air to blast it.

The speaker is very light. Feels like an empty aluminum sauce pan.
Well, not the end of it yet, there's also the alignment.

From the sound of the speaker on the table it doesn't promise too much, not as the 37-116 or Zenith Spinet dd, but Ithink with it inside the cabinet it'll be good enough.

[Radioroslyn]

> "Classic Gas"

Mike, Is that a flatulent reference? Or did you mean Classical Gas by Mason Williams?
Love that song!

[morzh]

Yeah, meant that one

Just about an hour ago I decided to go through the rest of the resistors and saw another cap under the preset stations' coils. Bummer. But luvkily, everything in this radio is easily moved aside, so two screw and 10 minutes later I replaced it. I am all out of tubular 0.047uF so had to combine and, since it wouldn't fit n the original shell, just put the caps directly. It is under the coils, unseen - myself missed it until looked specifically under the coils.
Had to change three more resistors in the AVC circuit.

Oh....and cleaned the volume pot, no longer scratchy.

Not sure what the value of either the volume and the tone ctl pots, the sch calls for two values for the tone ctl, one being 6M, but it measures at 12M, and works just fine.
The volume measures at 1M.

Enough for today, I need a can of air and D series Deoxit, and I have neither.

[KCMike]

Nice work Mike. Ah, how nice to have a rust free chassis to work on.

[morzh]

Mike, yes it is. I do not like rusted chassis'. THis one was barely dusty.

Now some pics and a question to those who have this radio (Gary, maybe to you).

First the pics:


On the bench with the speaker.
BTW, the nuts that hold the speaker do not lend themselves to any socket size from a standard set but work fine with 9mm metric.

   

After the recap.