[codefox1]

Probably don't need any bigger than 22 mfd for first filter given a 5 or 6 inch speaker which wouldn't go for 120 Hz or 60 Hz dependintg on whether or not this set has a transformer. Seccond filter can be 40 or 50 mfd, whatever is available with proper voltage limits.

[morzh]

Thanks guys. I will follow your advice then.


LASJayhawk

Which beer do you favor? I'm a stout and IPA man myself.

[LASJayhawk]

morzh: I like free beer best! stouts and ales mostly.

Most of tend to err on the side of caution, smoking an 80 year old power transformer can ruin your day.

[morzh]

It would, it most certainly would. It would also decimate my two-week beer supply

I just asked at work and they told me that piggybacking my order on the company order to save shipping charges by Mouser is no problem, so I am gonna stock up on those caps.

PS. I was wondering why I never found 16uF values on any sch of 80; your explanation seems the mostly likely one. Though I'd wonder - did the "lytics" croak this often back then, so they had to be replaced after 20 years?

I remember my childhood big toob radios, mfrd. in 50-s and being with us end of 80-s, working just fine. They used those same can caps, and, mind you, those were Russian-made, not the very best in the world, not at all.

[morzh]

Hey everyone, long time no see.....

Question1:

How do you secure new electrolytics inside the old aluminum can? (Both wires are insulated from the can). Will hot glue do?
Should I wrap everything in insul. tape first?

Question 2:
What do you glue the cut off top to the can with?

[morzh]

Well, today I've heard the strongest local station, "Good times oldies" from Lakewood NJ.

After I re-fitted all the Bakelite caps and re-stuffed the electrolytic caps (bought a bunch from Mouser - my company obliged piggibacking my order on theirs; otherwise the shipping is a killer with them), and replaced all the resistors, and washed the tuning cap, and...and.....when turned on, I realized one 36 type tube was not glowing, so I had to buy two tested tubes on Ebay.

So, with me acting as antenna, grabbing the antenna wire, I was able to tune in.
The music as not very loud. It is about where I would listen to it, but at the maximum volume setting.

I suspect I will have to tune the regenerative stage; after all the radio is really old and some parameters must have drifted by now.
Will have to look for the tuning procedure.

[codefox1]

Well, today I've heard the strongest local station, "Good times oldies" from Lakewood NJ.

After I re-fitted all the Bakelite caps and re-stuffed the electrolytic caps (bought a bunch from Mouser - my company obliged piggibacking my order on theirs; otherwise the shipping is a killer with them), and replaced all the resistors, and washed the tuning cap, and...and.....when turned on, I realized one 36 type tube was not glowing, so I had to buy two tested tubes on Ebay.

So, with me acting as antenna, grabbing the antenna wire, I was able to tune in.
The music as not very loud. It is about where I would listen to it, but at the maximum volume setting.

I suspect I will have to tune the regenerative stage; after all the radio is really old and some parameters must have drifted by now.
Will have to look for the tuning procedure.

our voltages are about 10% high, and that does not bode well for tube life. I'd get a bucking transformer installed if you have room to tame it.

[morzh]

our voltages are about 10% high, and that does not bode well for tube life. I'd get a bucking transformer installed if you have room to tame it.

A bucking xfmr should not be that large, should it? never saw one, but from the way it works, it may be made quite a bit smaller than the auto or a full step-down.

Do you know a good place to buy one, 120/110V type?

[codefox1]

our voltages are about 10% high, and that does not bode well for tube life. I'd get a bucking transformer installed if you have room to tame it.

A bucking xfmr should not be that large, should it? never saw one, but from the way it works, it may be made quite a bit smaller than the auto or a full step-down.

Do you know a good place to buy one, 120/110V type?

See attached. Many variations on this but this is simplest.

[morzh]

Today decided to look at the sch again - the radio played not loud enough.
Sure enough, in the 2nd detector I soldered the load (10K resistor) to Screen Grid, not to the Plate.
Now this thing is really loud.

It pulls only one station, the loudest one around.
Still have not tuned it.

Q1: Anyone knows of tuning procedure, and where I can find a good guide for it (tuning the IF filter etc, tuning the Regen. of the 2nd detector).
Q2: The Det. oscillator has a mica cap of 710pF / 10K resistor feedback in the Cathode. Has anyone needed to replace those? The 10K resistor measures 11.4K, the cap, of course, cannot be measured without desoldering.
The problem is, it is all inside the aluminum can, and it is riveted, and unless really necessary, I'd prefer not to go inside.

[Radioroslyn]

[quote='morzh' pid='26281' dateline='1331961277']
Today decided to look at the sch again - the radio played not loud enough.
Sure enough, in the 2nd detector I soldered the load (10K resistor) to Screen Grid, not to the Plate.
Now this thing is really loud.

It pulls only one station, the loudest one around.
Still have not tuned it.

Q1: Anyone knows of tuning procedure, and where I can find a good guide for it (tuning the IF filter etc, tuning the Regen. of the 2nd detector).
Q2: The Det. oscillator has a mica cap of 710pF / 10K resistor feedback in the Cathode. Has anyone needed to replace those? The 10K resistor measures 11.4K, the cap, of course, cannot be measured without desoldering.


Tuneup is the same as all superhets. Adjust IF trimmers for peak at IF frequency (470kc)With the dial set at 1400kc, two trimmers on the tuning cap adj for loudest signal at 1400kc. Adjust the regeneration control till it squeals then back it down a 1/4 turn.
If the set is working I wouldn't bother to pull the IF can apart, unless you wanted to change the grid leak resistor.
Terry

[morzh]

hey Terry

Thanks for advice. No I don't want to change grid leak resistor, it is 11.4K i/o 10K, and I think it is fine the way it is; the cap is mica and is probably OK.
And the radio works, so it needs some tuning but nothing drastic.

Interesting, I used one of the original #36 tubes (another one was cooked, the filament's gone), and it did work, but I made a smart choice of buying two tested tubes, and, after the radio worked, I tried the original; it did work in the Det.-Osc. stage, I saw no difference in amplification, but it did not work in the Second detector (regenerative); I could barely hear anything.

Judging by sound, the Audio is OK.

Need to buy me a signal generator to tune the IF. And (sigh) to explain it to me ol'lady.

[Radioroslyn]

hey Terry

Thanks for advice. No I don't want to change grid leak resistor, it is 11.4K i/o 10K, and I think it is fine the way it is; the cap is mica and is probably OK.
And the radio works, so it needs some tuning but nothing drastic.

Interesting, I used one of the original #36 tubes (another one was cooked, the filament's gone), and it did work, but I made a smart choice of buying two tested tubes, and, after the radio worked, I tried the original; it did work in the Det.-Osc. stage, I saw no difference in amplification, but it did not work in the Second detector (regenerative); I could barely hear anything.

Judging by sound, the Audio is OK.


Actually the grid leak is the 3 or 4 meg resistor in the grid circuit.
Terry

[LASJayhawk]

That is kind of interesting, the 2 #36 tubes in my 80 when I got it tested weak, but identical on my Hickok, but only one would work in the 1st stage.

It took me 3 tries over 3 days to get the alignment right where the dial tracked and there wasn't a change in volume at the low or high end when I touched the 1st 36's grid.

But I'll tell you what, the little guy works pretty good, abet the volume control is a little 'jumpy'. Not bad for a radio Philco didn't want to sell.

[morzh]

18 bucks a pop...not too shabby for a superhet.