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Bought my first cathedral.
#16

". . . dinky, . . . "   Icon_lol
#17

Also the bigger transformer is more reliable.

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.
#18

You got lucky if you're only missing a 80 rectifier. They are plentiful and very reasonably priced. Take care, Gary

"Don't pity the dead, pity the living, above all, those living without love."
Professor Albus Dumbledore
Gary - Westland Michigan
#19

I was told by an old timer back in the 70's that for each finger width of core on a transformer that has a hv winding the finger width = abt out 100ma of current capability from that hv winding. Almost 50yrs later I say sometimes.

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
#20

Gary i got two spare 80's laying around i have been wheeling and dealing with a local collector that has a large stash and tube collection.
#21

Just wondering how well it is going to perform.
#22

The performance is meh....same as 20 or early 70.
I'll give you a hint: Plate detector.

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.
#23

Well i live between two blowtorch stations wsm and whas they come in pretty strong day and night so it shouldn't have trouble.
#24

It's not that. Plate detector is, well, further from HiFi then the rest of'em.

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.
#25

So it will sound like a tin can.
#26

Well that's a good question.

You might have noticed by the schematic that the 50 is a trf set. Trf stands for tuned radio frequency in layman's terms it means that it a couple of rf amps, a detector and audio ouput stage.

+'s
It's not particularly selective so the audio frequency response is typically better than the average superhet.

Easy to service/simple design.

-'s
Broad selectivity may have it hard to separate strong stations that are close in frequency.

No avc. This means that as you tune across the dial if you set the volume control so the strong station is at a comfortable level weak station won't be heard and vice versa adjust it for a weak station and the strong station will be very loud.


I little trickier to connect an external audio input to as the the "volume control" controls the rf gain and the level of signal that comes from the ant. This is why the volume control has two sections.

Not sure about distortion from the detector stage but if it seems excessive there are way to deal w/that.

Common issues are caps, out of tolerance resistor (20%) is spec, open primaries on the rf coils. I had one w/a replacement power transformer, since that set uses 2.5v tubes the pt is hard to come by and expensive.
Always good to check output transformer and field coil for resistance.



GL

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
#27

I don't use external inputs it isn't my thing. I will check all the usual items but i usually don't do full restores i get them working safely i replace the bad and keep the good and all the old parts go into a box for safe keeping just encase the next owner wants to restore it back to how it was.
If all checks well i will replace the caps and resistors inline with the power supply and see if it works ok.
#28

This you tube might help in understanding HZ.   https://www.youtube.com/watch?v=vGFgDSkdZjM




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