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Hallicrafters S53-A
#31
I got parts in today, gary at play things of the past sent me a few 100pf caps and two automatic manuf corp complete IF's.

so,, i got rid of the T10 silver mica caps and installed 2) 100pf caps in thier place.


after omitting the T10 mica caps in trade for replacements, now my voltage holds steady.
with my sensitivey fully cw, my voltage is only 180vdc.  with the sensitivity fully ccw, my voltage sits at 205 "ish" vdc.

I am able now to turn on the radio and not over heat anything. 

My new problem is now there is nothing coming out of the speakers.

I am wondering if the capacitor size is incorrect?????????

when i turn on the set some volume is audible and within the time the tubes start coming on line, the loudness goes nearly to nothing.

when i switch the band selector, i hear nothing in the speaker , no static or anything.

On my schemitic, up on t10, i have 180 to 205vdc appearing on pin 4 depending on the position of the sensitivey knob.

I have the same voltage present on pin 3,, i for some reason expected to see less on pin three,

the radio is still inop but i need help knowing where to go from here.
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#32
The next step would be to use a signal generator to align the IF transformers.
"Just because the microphone in front of you amplifies your voice around the world is no reason to think we have any more wisdom than we had when our voices could reach from one end of the bar to the other"     Ed Morrow

Terry
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#33
before i go into the expense of that and the waiting for the sig gen & the freq sensor (10$ unit you recommended) which isnt a problem, how to i confirm that is true?

i guess i couldl go back through my voltage readings to verify they are meeting the specs within the manual.
that tells me i am back to where i was when the set initially went to a no sound state.


i am back to where i was,,,
when i power with volume at about 80% i hear what seems to be only 20% volume.
after the tubes come on line, the volume ramps down to the point its nearly impossible to hear. but I then set the volume to 100% and it sounds like its putting out sound like 10%.

With these new caps installed, the symptoms are all lower audible levels than before.

when i intially powered up with the replacement caps on T10, i did hear some additional poping noises.

I looked into the patent of the IF's and apperently even in the write up the wording implied that it was not nessessary to provide values for individual components!, seems like it was secret squirril stuff.

I have two replacement IF's with a supplier name on the container called STAG. i am going to see if there are data sheets anywhere on line for Stag.
there is one youtube vid where a S53-a was the radio being worked and in this one single vid pertaining to silver mica caps, the guy discovered that in this set T10 was a totally different ferad rating CAP. He assumed 100pf and was running his slugs too far out and started over then discovered this. The manual says T10 & 11 are the same pn from T12. He discovered there may be an error in the manual,, and that T10 , the one closest to the antenna is actually different.
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#34
Here is a much better schematic easier on the eyes.

the reference to the IF is incorrect, along the bottom postion 3 & 4 need swapped to represent visually matching how its installed.


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#35
here are my voltage readings setting the chassis up per the instructions.

A STAR means large problem areas.
also, my sensitity tests seemed backwards but i dont think i need to focus on that right now.

see picture


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#36
with the sensitivity knob rotated the other way fully ccw, my problem areas fall close to what the table tells me i need to meausre so..... i guess these areas marked with a star are not a problem after all.
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#37
Since i know that i have weak sound, holding the speaker to my ear, i did notice that if i put the radio in CW i could hear a couple random stations while on broadcast.
It was suggested i simply play around with the IF's coil adjustments in order of adjustment 1 through 6 to increase.

That worked right away and allowed me to barely hear a couple stations even after i switched from CW to AM.

I went through several times to fine tune S1 through S6 on the three IF slugs till i finally felt like i was at max DB.

All this is with my radio at 100% volume and the noise i hear on the speaker is what seems like i have the knob at only 10%.
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#38
There is something that I ,,,,DO,,,I check all new caps ,,,all the time,,,,,because ,,,had a bad one that ,,,,made this same situation,,,hope you find this little problem ,,,CHEERS
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#39
I'd like to do that with the caps live under load in the circuit so i can do the amp/volts readings then do the math to see were each cap is at compared to its stamped rating.

problem is i dont have an amp clamp solution small enough to wrap around the + lead of each one.

I dont want to desolder and put my meter in series each time.

do you have a solution to get the amp reading on each cap wihout desoldering?

Ive never had to desolder on larger caps because there's always been wiggle room enough for individual wires leading to the larger caps ive messed with in the past.
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#40
Sorry,,,don't have,,,,I just cut one end close to solder ,,, then read 'em,,,,
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#41
The easiest way to check the caps is with an older capacitor tester that can place the cap under load.  The vintage Sprague, Heathkit, and Jackson capacitor testers will test leakage with anywhere from 400 - 600 volts (real life working volts), something those modern handheld Chinese units can't do.

I've been using an old Jackson 650A for years (with a Heathkit as backup):

http://www.californiahistoricalradio.com...hould-own/

The Sprague Tel-Ohmike are considered the Cadillac of vintage capacitor testers by some, but they usually sell for a premium price and one of the lesser names will serve you just as well.

http://boatanchorpix.x10host.com/CapChkrs.htm
John KK4ZLF
Lexington, KY
"illegitimis non carborundum"

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#42
When troubleshooting a radio, I work from the audio section back to the IF stages, then osc, and RF last.

A couple of things I see here. First you need to verify the audio section is working properly. You can turn the volume up and put you finger or a screwdriver on the wiper. You should hear a loud hum. If not, you need to fix the audio section. The voltages look right, but maybe you have a bad speaker. I have seen them open up. Your speaker is on the top so it's prone to all kinds of things getting into it.

If audio section is good, check the radio/phono switch. If intermittent or open you might get enough audio to bleed through causing your symptom.

What looks bad is the screen voltages being too high around the IF amps, almost source voltage. The tubes are not drawing enough current. I had one of these sets about 35 years ago with the same symptoms and it was a bad IF transformer. No SMD just an open winding. I would check all IF coils for being open. Since you had them out, anything is possible.

If you are not certain about the oscillator, grab another radio and tune it to approximately 1.445. Then tune the S53 back and forth around 1.0 on the BC band. If working, you will hear the other radio get quiet and then noisy as you tune the S53 back and forth. I'm guessing hi side injection, so the S53 osc would be 455KHz above the dial freq. if this is not working, then troubleshooting the osc coils and band switch are in order.

A signal generator is great for this as you can inject the IF frequency and you should hear it loud and clear in the speaker. If good you work back to the front end of the radio. Also, do test and or substitute tubes.
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#43
Tbone
answers
-bare finger touching the cap lead on the vol ctl introduces speaker hum at a louder DB.
-multiple speaers used to verify oem speaker is not bad.
-open / close the phono-speaker switch produces proper affects.
-my IF T10 nearest the antenna reads 9ohms on both the pri and sec, i repaired the SMD part with new 100pf caps. Previous to this i had some degree of continuity from T3 pin 1 to T3 pin 3, now its fixed.
T11 and T12 both read 15ohms pri and sec and i dont see reasons to open up these IF's "yet" to rework the silver mica caps but we will see.

-placing a transistor radio near the hallicrafters S53 and tuned like you said produced the results you mentioned.

at this time i still feel compelled to replace the caps in T11 and T12.

i made a discovery a few nights ago that when i flipped to CW, i heard something on band 2 in the middle like Ham guys.
it was suggested a fiddle with the IF's to bring that receptions DB up a tad in volume and it worked.

i went back to the cw/am switch and picked AM on band 1.

in the middle somewhere i was now barely hearing a station with the volume at max.
In order of the manual operation i adjusted S1-S6 slugs in all three if and was able to increase the DB. with vol at max i can hear a couple stations but sound is like my volume is at like 15 or 20%.

wating on gear to arrive to continue.

I just settled on purchase of a siggen and a freqgen on ebay.

Fordham SG-490 Wide Band Signal Generator 0 KHz -150 MHz
Global Specialties MAX-100A 100MHz Frequency Counter
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#44
I think i need to replace the two remaining IF caps and here is progress so far.
tell me if you think i am right ,  i barely know what i am doing here, this is OJT to me.
I open both tuning caps
I add a .1uf cap but have no idea what they mean by adding it to the high side of the tuning cap so i assumed it meant wherei have it now.
i inject the 455kc
over the past few days i have fiddled with the IF's slug adjustments so much they were totally jacked up.
I finally was able to adjust the IF slugs to get decent volume out but by ear its feeling more like 50%.
I use to be complaining about 20% volume with the knob at max so this feels like progress to me.
I peaked these three IF's (six slugs) by ear but since i suspect my ear is not good enough,,,,,next i added in my meter to the headphone jack and selected headphones.
I started over again peaking the IF's to max millivolt readings.
This helped get me to where i am now, the vol knob is at max but the sound by ear tells me the radio suffers from some degree of low volume.
TO the slugs.........
I noticed in order to get where i am now,  nearly all my slugs are bottomed out.
I replaced the caps on my first IF which is T10 with two 100pf caps.
The other two IF's still have the silver mica stationary caps.
I only have 2) 100pf caps remaining in my hoard.
to the question now..........
would the remaining IF's T11 and T12 stationary caps being boarderline faulty cause a symptom of poor or low "ish" volume?
If yes, if you had only two 100pf caps, which IF would you trow your last two 100pf caps at?
Back earlier i mentioned a buy on youtube who thinks my last IF T10 requires a larger pf cap than 100.
I notice this difference........
T10 slugs have 12 rotations each of adjustment.
T11 and T12 have six rotations of adjustment.

I just harvested parts from our old Tube TV and on the circuit board there are many coin shaped caps in the 1kv and 2kv ratings, i will see if there are some PF caps on this board or other PCB's i have saved back for spare parts.


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#45
also,
could i have abused where i installed ceramic caps?

i just heard that ceramic (flat round coin shaped) caps should never be installed in an oscilator circuit.

when i got rid of my wax caps, i installed what i had which to this point was a combo of the yellow one and the ceramics.

could this be part of my issue?

here is a pic of the busy end,, to show the qty of yellow caps vs disc caps


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