[morzh]

That is an excellent tube then.
I have seen many rectifiers that are weak and need replacement and, honestly, am yet to see the original one in the AA5s I have fixed over time. Not to say that I won't see it one day.
Long live Westinghouse!

[captainclock1988]

Well another interesting thing is that I have a 1952 Zenith "Bugeye" clock radio (AM/FM model) that I had picked up at Goodwill for $5 and some change and it worked perfectly with all of it's original components in it yet including all of it's original tubes, but then about half a year later the filter caps started failing (the radio started humming) and so I took the radio apart and recapped it and it's been fine since, and this westinghouse is basically a clone more or less of this Zenith except that the Zenith doesn't have the rectifier tube like the Westinghouse does, but earlier versions of these Zenith 6 and 7 tube wonders did have a 35W4 rectifier tube in them before they went solid state with the rectification circuits.

[morzh]

Well...I have done many a Philco, and the 80 tubes in them often test weak or borderline.
However as long as it is not VERY bad, I use them and they work just fine even if test weak-ish.

PS. I never had an original 80 tube in any of them; they always some other mfr.

[captainclock1988]

Interestingly enough my Philco 116B that I've been working on had almost all of it's original tubes in it except one of the 76 tubes (which had an old rectifier tube in its place for some reason) and the 80 rectifier tube wasn't original but the rest of the tubes were all the original Philco Branded Tubes.

[captainclock1988]

OK, so how critical is output transformer placement? I'm asking because in my radio the ouyput transformer was originally mounted under the chassis and the new output transformer I ordered it too big to fit under the chassis and so I was thinking of mounting it above the chassis next to the speaker.

Would it be ok to mount the output transformer above the chassis on this radio or should it stay under the chassis?

Also my output transformer has two secondary windings a 6 or 8 Ohm winding and a 3.2 or 4 Ohm winding, and in my radio's case I need the 3.2 Ohm Winding, how do I tell which winding is which? because when I go to ohm out the windings on the secondary side I don't get the ohm readings I'm expecting, I get something like .6 or .8 or something like that, not a full 6 ohms or 8 ohms.

[morzh]

1. Yes it is OK to place the output xfmr anywhere at all where it fits. Including on the speaker itself.
2. The numbers you have (6, 8, 3.2 and 4 ohm) are the loads, not your secondary resistance.
Depending on what your output speaker is, you use one or the others.
You should have the datasheet of your transformer that tells you by color or whatever what wire is what.

[captainclock1988]

Well unfortunately my transformer didn't have a datasheet with it, just a sticker on the box with a diagram that said which side was the primary which side was the secondary, but nothing that said which wire leads to use for 3.2, 4, 6 or 8 ohm speakers.

EDIT: Found the data sheet on the website I ordered the transformer from, and apparently I ordered the wrong one, the one I ordered was for push-pull service rather than single-ended use, they didn't even specify that on the product description, it was in the data sheet where I found that information.

[David]

   
The data sheet for the correct transformer looks something like this? If not could you post a picture of the data sheet for the correct transformer. One can never have to much info when working on old radios.

[morzh]

If it is a Hammond, their SE part number has "SE" in it.
There are, I think cheaper alterntives. Hammond is expensive.

[captainclock1988]

I was browsing on ebay and I found an output transformer that looks almost exactly like the one that was in this radio originally right down to the extra tap and the single secondary lead wire being soldered to the transformer body as a ground so that the speaker (which also has one lead attached to its body) can work through the radio chassis with only one wire lead attached to it.

the only difference is that the amp (more than likely a radio) it originally came out of was a single 6AQ5 tube amp, whereas this radio was a 35B5 tube, so I don't know if transformers care about tube voltage or not but I thought I would ask you guys first before I bought it, also how super critical is the primary winding's resistance rating? I'm asking because I also found a couple of NOS Stancor output transformers that have selectable primary and secondary winding taps for various resistance ratings and the lowest resistance ratings they had on the primary side was 500 Ohms and this radio says the primary winding is ~200 ohms but I'm not sure if there's a ± percentage that the resistance rating could be or if it really doesn't matter, the output transformers in question are linked below.

Replacement Output Transformer Option #1

Replacement Output Transformer Option #2

Replacement Output Transformer Option #3

Replacement Output Tranformer Option #4

Replacement Output Transformer Option #5

Replacement Output Transformer Option # 6


Hopefully one of these will work, let me know what you think.

Thanks.

[morzh]

Most times this would be sufficent:

Determine if SE or PP transformer is needed.
From the datasheet of the tube determine the expected impedance the tube wants to see in the amplifier class you have (SE which is A, or PP which is AB). They are listed in datasheets explicitly.
Find the transformer that says explicitly that it is, say, an SE transformer with the output, say, 8 Ohm (suppose you have 8 ohm speaker) and the matching input impedance. If the latter not listed, the square of the Primary to Secondary turns ratio is the conversion factor.
If you have 30:1 ratio of Prim/Sec your 8 Ohms will be converted into 8*900=7,200 Ohm.

And so forth,

[David]

OK my turn to muddy the water. After doing what Mike said to do, look at the wattage rating of the transformers. The more watts the more $$$$  so a 50L6, 50A5, 50B5, an 50C5 in a AA5 set max power output around 2 watts. Full volume on a AA5 set IMHO not something I want to hear. Putting a 10 watt trans in a AA5 set is overkill. In the future when going to yard sales or flea markets look for organ donors mostly 60s set with printed circuit boards. Plastic cases that are beyond repair and a cheap price. Stay safe David

[captainclock1988]

Well the 35B5 wants ~14,000 ohms on its plate, and the speaker on this radio is a 3.2 ohm speaker, this is a single ended output setup (only one output tube as opposed to two if it were a Push-Pull setup). 

So the 3rd, 5th or 6th option will probably be the best, because because they're all SE output transformers that can take about 14,000 ohms plate resistance and they're under $50 including shipping costs.

[morzh]

According to this

https://www.radiomuseum.org/tubes/tube_35b5.html

and this

https://frank.pocnet.net/sheets/049/3/35B5.pdf

it wants 2.5kOhm (2,500 Ohm) load, not 14kOhm.

So you want 27 turns ratio.

Secondary option xfmr has 2K to 3 Ohm, if this what they mean by the description.

[John Bartley]

Try this ::

https://www.hammfg.com/files/parts/pdf/125ASE.pdf

These should be available from Mouser, but I did not check to be sure. If you call them with this number they should be able to cross it to whatever they carry.

If that one isn't high enough plate current, try this one::

https://www.hammfg.com/files/parts/pdf/125BSE.pdf