1957 Fender Princeton (Amp Porn) Completely 100% Original / UNtouched.

Well...
powered up filaments only and steady at 6.1VAC with a line voltage of 119 VAC.
And so far the filaments are not a problem...
I plan to use an LED bulb for the pilot light, so maybe I can get the filament up to 6.3 VAC...without the incandescent #47 bulb installed.


LED is 100 mw VS. incandescent 945 mw
Si I might get a rise out of the filament volts...
 
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How? How is it so mint? I gotta bet @Amp Mad Scientist hasn't even aged that well!! :p

Time machine.

I spoiled it yesterday, I disconnected a couple of things to test the transformers before I fired up the filaments.
Now, it's "lightly" molested.
I didn't want it to let the smoke out :rolf:
I did feel the guilt of touching a virgin....desecrating the sanctity...but somebody had to do it.
 
Hey... Those are pretty cool (Pun intended)! I wonder if those have a little resistor built in?
 
Are the caps leaky? Are they stable? Gigging can really take a lot out in an amp. My tweeds are slowly begging for filter caps n I've been playin them on 110v. Seems I have everyone beggin me for them but I'll never get rid of another. Each time I'd say ridiculous prices to get them to stop . Shocked at how many songs of the past we've listened to were recorded with tweed champs. Mine is so loud for a little box but I'm afraid to use it up loud since I know the OP tranny windings are like the size of a hair! Very Highly Recommended Amp
 
Are the caps leaky? Are they stable? Gigging can really take a lot out in an amp. My tweeds are slowly begging for filter caps n I've been playin them on 110v. Seems I have everyone beggin me for them but I'll never get rid of another. Each time I'd say ridiculous prices to get them to stop . Shocked at how many songs of the past we've listened to were recorded with tweed champs. Mine is so loud for a little box but I'm afraid to use it up loud since I know the OP tranny windings are like the size of a hair! Very Highly Recommended Amp

I'm going to install F&T 500V caps for the high voltage and Sprague TVA 50V for the cathode bypass caps.
I'm rewiring the filaments balanced / cloth wire, and balancing the filaments to the chassis w/ 2X 100 ohm 1/2W resistors.
(previously one leg of filaments was connected to chassis) But that doesn't work with a 3 prong mains plug...
Adding the grounded (earthed) 3 wire mains lead, of course.
Remove the death cap.
Change the original pilot light holder over for non-grounded filament.
(previously, one leg of the pilot light was connected soldered to the chassis.) But again that doesn't work w/ a 3 wire mains lead. The filaments will now float instead of using the chassis as the 1/2 filament path....
Change pilot lamp #47 to LED, this is an experiment to see how bright the LED is going to be compared to the incandescent bulb.
Check / evaluate original tubes.
Clean controls and jacks.

I really hate to change the original resistors or coupling caps if they still work.
I'm hoping that the low mileage will see all of the resistors working OK etc.
 
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It's no longer virgin,,,,,I touched it.

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I use F&T caps because I think it makes the amp sound better.
What I notice is a very distinct "hi fi" type of sound when I install F&T....it's like an instant noticeable improvement.
Compared to others, I have been going for a more Hi Fi sound.
The Illinois Caps used by Fender sound really dull and lifeless to me, so I don't use those.
 
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I'm not a fan of Illinois either. I actually get upset when I see them worse when I listen to them!
Those Illinois caps sound gritty and muddy.
They don't last very long either.
In case anybody is just tuning in, "Illinois Capacitor" is made in China.
It has nothing to do with Illinois.
Illinois is a state of the USA.
But this is the trend. To make products in China, and to make them seem like USA products.
They especially like to put USA names on products made in China.
 
Those Illinois caps sound gritty and muddy.
They don't last very long either.
In case anybody is just tuning in, "Illinois Capacitor" is made in China.
It has nothing to do with Illinois.
Illinois is a state of the USA.
But this is the trend. To make products in China, and to make them seem like USA products.
They especially like to put USA names on products made in China.
Theres a crazy assed cartoon on Adult Swim called China, IL coincidentally lol
 
Theres a crazy assed cartoon on Adult Swim called China, IL coincidentally lol
It sounded kind of swanky. I was surprized by how loud that Utah speaker was.
I cranked it up, and it worked but....
The Astron coupling caps were leaking. Fair amount of audible 120 Hz hum.
220K Grid leak resistor for 6V6 was open. (fried by the DC leaking through the coupling cap).
Damn, I hoped that those Astron coupling caps were still working but Noooooooooo.
397 VDC plate
338 VDC screen
198 VDC preamp V1A plate
189 VDC preamp V1B plate
5.92 VAC filament / with LED pilot light installed.

So now, scraping up some coupling caps somewhere...
dadblarnit.png
 
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It sounded kind of swanky. I was surprized by how loud that Utah speaker was.
I cranked it up, and it worked but....
The Astron coupling caps were leaking. Fair amount of audible 120 Hz hum.
220K Grid leak resistor for 6V6 was open. (fried by the DC leaking through the coupling cap).
Damn, I hoped that those Astron coupling caps were still working but Noooooooooo.
397 VDC plate
338 VDC screen
198 VDC preamp V1A plate
189 VDC preamp V1B plate
5.92 VAC filament / with LED pilot light installed.

So now, scraping up some coupling caps somewhere...
View attachment 57247
Oh you got this one man. Name aint Amp Mad Scientist for nothing!
 
Did you run the amp on 110v? On another note I've just found, in a shipping container, in a second story of a remote barn, 9 BF Princeton Reverbs, 4 BF Deluxe Reverbs, White Bassman, Tweed Harvard, and a Magatone but that's a 60's one W/ the plastic cabinet and some more I can't honestly remember. At least the barn has a small AC Unit up stairs! Pics to come exactly as I found them
 
Did you run the amp on 110v? On another note I've just found, in a shipping container, in a second story of a remote barn, 9 BF Princeton Reverbs, 4 BF Deluxe Reverbs, White Bassman, Tweed Harvard, and a Magatone but that's a 60's one W/ the plastic cabinet and some more I can't honestly remember. At least the barn has a small AC Unit up stairs! Pics to come exactly as I found them
119 VAC gives me 5.92 VAC filament at the moment...so I really don't want to drop the line voltage to 110.
If the filament was more than 6.3 VAC then I might want drop the line voltage.
(I already boosted the filament volts by installing the LED pilot bulb)
LED is 100 mw VS. incandescent 945 mw
The power transformer seems OK other than the filament is 0.3 VAC lower than I would 'like' it to be.
The transformer doesn't really seem "bad."
Different valves / tubes might have less filament current. I am using the original factory 1957 tubes.
Different valves might raise the filament volts a little bitty bit.
 
So now, scraping up some coupling caps somewhere...
Right off the bat, for very affordable and very good caps, the polypropylene Mojo Dijons and the polyester Synergy Royal Mustard caps. Valvestorm.com is an excellent supplier and vendor.

I also just recently bought a few ERO (Vishay) MKT1318 polyesters to try, also at Valvestorm.com, at the suggestion from Sir Ivan the Wonderful. If you're in a pinch and still live in San Luis Obispo, I have extra Mojo Dijons, extra orange drops 715s & 716s (polypros), and extra old SOZOs (polyester) that you can choose from and use.
 
Right off the bat, for very affordable and very good caps, the polypropylene Mojo Dijons and the polyester Synergy Royal Mustard caps. Valvestorm.com is an excellent supplier and vendor.

I also just recently bought a few ERO (Vishay) MKT1318 polyesters to try, also at Valvestorm.com, at the suggestion from Sir Ivan the Wonderful. If you're in a pinch and still live in San Luis Obispo, I have extra Mojo Dijons, extra orange drops 715s & 716s (polypros), and extra old SOZOs (polyester) that you can choose from and use.
I used this and it's Mallory, 630 volt. $1.27 each
One problem is the reach of the leads, on a point to point Fender board. It needs to be at least 3-1/2 inches long to reach the holes on the board.

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