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Philco 86 restoration
#31

>Can you slide a thin knife blade, or something between the case and the contents to separate them? 
I kinda doubt it. They are wedge in pretty tight and still have to get them loose at the top.

Some folks will go to the thrift store and pick up a toaster oven large enough to accommodate the cap can and use that to heat in up. You could do it in the garage so Mrs Mike doesn't catch wind of it. Temp wise around 210-225deg that will soften it up but take some time like 1/2 hour or so. You run it hotter but too hot it will damage the paint job and maybe catch fire.

I don't  remember how the can fits on to the base but perhaps you could wire up the new caps onto terminal board mount that to the chassis then fit the top cover later. Seems like part of it snaps together. I try to get thing done and working all at once but waiting isn't my strong suit.

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry
#32

Caps fit just fine - same exact arrangement was n 111, and they could be put there before the can goes over.
And yes, getting a junk toaster oven is a good idea.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#33

This is the capacitors mounted on the strip. I could put it in before I clean the can.


   
   
   


The cap from hot to antenna I made XY rated safety 10nF.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#34

So today I put this panel in, screwed it down.
Forgot to solder it in.
Turned over, powered. Zero volts. Took me about 4 minutes to come to my senses. ;)
Luckily, no shorts (power wires were hanging inside) or otherwise bad things.

So I soldered everything.

Good thing about this radio, the B+ is loaded by a resistive load from the start so the caps do not experience large voltage rises before the tubes warm up, so I could safely use 400V caps where otherwise I'd use 500V.

The speaker is in pristine condition.
I pulled it out, plugged in. Powered.
The radio produced typical noises, hum dependent on tuning, some howling and a distorted weak station, all with no antenna.
The "local" mode where the Line is used for an antenna did not help.
I disconnected the antenna from Local, touched it with my finger and was able to receive my local station. It is not yoo loud and it is at full volume.
I suspect the radio is badly misaligned, plus needs neutralizing.

But.... it's a good result.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#35

The 100 ohm resistors have caps inside them. Supposed to be 0.1uF. Test at 0uF (well shows 140pF at the meter showing 110pF at nothing).

   

Luckily the lead of the cap is easily unwound from the holder that grou ds it and then cut.

   

The new cap goes under the resistor.

   

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#36

The reception is much better and less garbled. It figures.

PS. I failed to neutralize the RF.
It is possible it was due to bad decoupling caps. Tomorrow will try again.
Also 120Hz hum is still there, not dependent on the vo!ume.

A note: for neutralizing I use a bad 26 tube, which has no shorts but has open filament. The Rider's book recommends pretty much the same: a 26 with a filament pin bitten off. I found one such tube in my possession. I think it is ok, instead of constructing a transition socket.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#37

The neutralizing procedure worked this time. With the bad tube with the open filament.
The sensitivity is good, many stations are pulled.
The hum - I realized I forgot about the R30, and when turning it, I was able to bring it down to very low level but it is very scratchy so I gave it a bit of Deoxit and will wait an hour before re-attempting it.

The distortion remains a bit, but looking at the detector, I think this is as good as it gets with this arrangement.

I think that's it, will put it back in the cabinet, maybe tonight.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#38

And onward to the 19LZX right???

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry
#39

Dunno 'bout that.
I might try to tackle a couple of Eico HF22 amps I have, to finish my second stereo system.
I also have a 16X console and (not sure I will get to it ) a Huge Stromberg Carlson I was given. And then another SK which I bought so his one I'd like to do.

But who knows....

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#40

Just realized the power switch has to be either rebuilt or replaced. So putting it back to the cabinet will have to wait.

Here it is.

   

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#41

Well,

When I put everything in the cabinet, the hum became really pronounced.
This is the hum that is independent of the volume.
I put it back on the bench, and traced the hum to the 1st AF driver, a 26 tube.
Pulled out, the hum stops.
Shorted to GND with a wire or a cap grid when in also stops the hum.

The suspect: the Interstage transformer between the detector and the AF. The output windng ohms out at 6,000 Ohms.

Questions: 1. Has anyone else experienced the hum problem, 2. Is the 6,000 ohm the right resistance for the interstage xfmr secondary? The one mentioned before.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#42

What I'm a gonna try is to introduce the AC filtering: this radio has it not, and I had exact same symptom in my 16 when my input cap pair had missing connection to the chassis.
Slim chance but....

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#43

The filter caps didn't do it.

Then I put the cap between the earlier mentioned transformer #22's pins that go to the 26 tube grid cap and #24 inductance. I thought of trying to eliminate the common mode noise that could somehow get through via xfmr's parasitic capacitance by shorting it via that cap.
This did have an effect: the hum went down significantly, and the distortion I complained before all but disappeared.
I am not sure I understand where the noise comes through in first place: it is not from detector, as it remains if the detector tube is out or its grid is shorted, but the xfmr is shielded. Then touching the chassis anywhere including the xfmr shield would increase the hum.
This all could be due to the different cathode potentials, but they are all tied together by that big resistor and decoupled with capacitors.
If it is what I think (CM noise) the same cap from the other primary pin and the GND should've worked too, but it didn't.

I even thought of eliminating the transformer altogether as it can be simply replaced with a cap and two resistors, but decided to not do it.

So....I decided to take it and be done with it.
Tomorrow will put it into the cabinet again and see how it works.

It sure sounds much nicer now.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#44

Question ???? I would like to know,,,IF,,,you have ever pulled the capacitors ,,,out of the resistors (wire wound ones ),,,??? thank you
#45

No. I cut one of the leads and then put the new caps outside.
I actually wrote about it and supplied the photos.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.




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