Just got this in... NOS. P-6314.
From the box:
700vac CT @ 200mA
5vac @ 3A
6.3vac @ 5.5A
It says nothing about a center tap the on the box but the reference to the part # says it should have a center tap.
Which is it?
Does anyone have a wiring diagram...?
I fanned out the leads a bit for the picture.
3 solid core white(?) wires, (one of these is actually 2 solid core wires in the same jacket) 2 solid core and one smaller stranded greenish(?) wires all from the hole on the right.
3 stranded white(?) and 2 stranded black(?) from the hole on the left.
I can figure it out if i have too but I thought I would post here first.
Old Stancor PT Wiring
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dorrisant
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Old Stancor PT Wiring
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Re: Old Stancor PT Wiring
Ouch. Should have eight wires at most, but has eleven! And they're ALL dirt color. How are you supposed to tell?
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dorrisant
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Re: Old Stancor PT Wiring
HT & CT = 3 
5v = 2
6.3v = 2 or 3(w/CT)
Pri = 2
+_______
9 or 10(w/CT)
8?
5v = 2
6.3v = 2 or 3(w/CT)
Pri = 2
+_______
9 or 10(w/CT)
8?
All in good fun, trust me I was laughing when I read that...xtian wrote: That's me. Helping.
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andresound
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Re: Old Stancor PT Wiring
Try washing/cleaning the wires???
If it sounds good, it is good! Trust your ears
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Stevem
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L
The wires might be cleaner and give you a clue if you pull the bell cover off, and do such very careful as you pass the wires thru the bell!
Of course a resistance / ohms test should tell you what you need to know and with Stancor there center tap wires always had a yellow stripe .
Many times I jump in from another amp the filament voltage to prove out that I have guessed right.
A old small PT from a SS amp and and 1/8 amp in line fuse is good to have on hand for doing the same test!
On any old used PT like this that I have proved to be good I do take the time to pull the bell cover and epoxy the wires to the there exit point of the core.
Why you ask, well once on a build with a old PT like this I had the whole amp done and when to get the PT wires into a better layout and when I moved one of the rectifier leads one last time in snapped off inside and the total time to take things apart , unwrap the core and get that lead powered again was near 4 F-Ing hours!!!
Of course a resistance / ohms test should tell you what you need to know and with Stancor there center tap wires always had a yellow stripe .
Many times I jump in from another amp the filament voltage to prove out that I have guessed right.
A old small PT from a SS amp and and 1/8 amp in line fuse is good to have on hand for doing the same test!
On any old used PT like this that I have proved to be good I do take the time to pull the bell cover and epoxy the wires to the there exit point of the core.
Why you ask, well once on a build with a old PT like this I had the whole amp done and when to get the PT wires into a better layout and when I moved one of the rectifier leads one last time in snapped off inside and the total time to take things apart , unwrap the core and get that lead powered again was near 4 F-Ing hours!!!
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Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Re: Old Stancor PT Wiring
Tony,
I've worked with several old Stancor transformers. They made a great product in the day. Steve gives good counsel. Unfortunately, the insulation can get brittle over time. FYI, the 1948 Stancor catalog says list price was $10,70, so this was a fairly expensive item and I assume back in that era price and quality were actually related. Congratulations on a great find!
As Steve notes, it is best to first use your Ohm meter to test for continuity. This will verify the pairs and identify the center taps (which will meter half the value of the outer legs.)
Like Steve, I use a filament (6.3V or 5V) transformer to verify identification of the windings. I get everything screwed down and insulated for safety and use a screw-down terminal strip to feed voltage to the pairs one at a time. From there, it is simply about the turns ratio. If you feed 6.3V to the primary, I'd expect about 40V on the 700V winding, but you'll probably find that you can't tell the difference between the 5V and the 6.3V windings. For that reason, I usually run it in the other direction. Supplying 6.3V into the 6.3V winding will give you about 115V on the primary and 6.3V into the 5V winding will give you about 145V. The HT winding is a ratio of about 1:6 (primary:secondary), so feeding 6.3V on that secondary creates a 1/6 step down, so I'd expect about 1V on the primary for that, which is why you do better to test the HT by feeding voltage to the primary.
As for colors, experience allows me to see more than "dirt color" LOL. This is what I see:
-This side with 5 wires, 2 black is primary, 3 red are HT secondary. If you look very closely, you'll probably be able to choose the CT wire visually.
-The side with 6 wires, 3 green are 6.3V and 3 yellow are 5V. Again, close inspection might indicate which is the CT for each of these windings. Center taps, while not clearly indicated on the label, are specified in the 1948 catalog, so 11 wires is, indeed, the correct number!
Good luck with this.
Phil
I've worked with several old Stancor transformers. They made a great product in the day. Steve gives good counsel. Unfortunately, the insulation can get brittle over time. FYI, the 1948 Stancor catalog says list price was $10,70, so this was a fairly expensive item and I assume back in that era price and quality were actually related. Congratulations on a great find!
As Steve notes, it is best to first use your Ohm meter to test for continuity. This will verify the pairs and identify the center taps (which will meter half the value of the outer legs.)
Like Steve, I use a filament (6.3V or 5V) transformer to verify identification of the windings. I get everything screwed down and insulated for safety and use a screw-down terminal strip to feed voltage to the pairs one at a time. From there, it is simply about the turns ratio. If you feed 6.3V to the primary, I'd expect about 40V on the 700V winding, but you'll probably find that you can't tell the difference between the 5V and the 6.3V windings. For that reason, I usually run it in the other direction. Supplying 6.3V into the 6.3V winding will give you about 115V on the primary and 6.3V into the 5V winding will give you about 145V. The HT winding is a ratio of about 1:6 (primary:secondary), so feeding 6.3V on that secondary creates a 1/6 step down, so I'd expect about 1V on the primary for that, which is why you do better to test the HT by feeding voltage to the primary.
As for colors, experience allows me to see more than "dirt color" LOL. This is what I see:
-This side with 5 wires, 2 black is primary, 3 red are HT secondary. If you look very closely, you'll probably be able to choose the CT wire visually.
-The side with 6 wires, 3 green are 6.3V and 3 yellow are 5V. Again, close inspection might indicate which is the CT for each of these windings. Center taps, while not clearly indicated on the label, are specified in the 1948 catalog, so 11 wires is, indeed, the correct number!
Good luck with this.
Phil
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dorrisant
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Re: Old Stancor PT Wiring
Thanks for the help guys but my dreams are slightly shattered.
I had figured that the two stranded blackish wires were primaries. I tested all other windings for resistance and came to the conclusion that Phil posted. I took the bell ends off and the colors weren't any clearer.
I have a 13vac wall wart that I put on the variac and drop to 10vac for easy OT secondary calculations... also good to put on the primary of this PT... hooked it to the primaries and nothing shows up anywhere. I was suspect of this because DCΩ measurement had showed it to be open.
When I backfeed it through the suspected filament taps, the secondary winding shows over 500vac.
Sadly it seems the primary winding is open. Again...
I had figured that the two stranded blackish wires were primaries. I tested all other windings for resistance and came to the conclusion that Phil posted. I took the bell ends off and the colors weren't any clearer.
I have a 13vac wall wart that I put on the variac and drop to 10vac for easy OT secondary calculations... also good to put on the primary of this PT... hooked it to the primaries and nothing shows up anywhere. I was suspect of this because DCΩ measurement had showed it to be open.
When I backfeed it through the suspected filament taps, the secondary winding shows over 500vac.
Sadly it seems the primary winding is open. Again...
"Education is what you're left with after you have forgotten what you have learned" - Enzo
Re: Old Stancor PT Wiring
^^^What Jelle said. Sorry that it didn't work out.
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dorrisant
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Re: Old Stancor PT Wiring
Thanks guys but no worries... I got a refund.
Shopping for a PT again. Anyone have anything on the shelf they would let go of? I may just go ahead and order an Edcor. It just takes a while to ship.
Shopping for a PT again. Anyone have anything on the shelf they would let go of? I may just go ahead and order an Edcor. It just takes a while to ship.
"Education is what you're left with after you have forgotten what you have learned" - Enzo
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RJ Guitars
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Re: Old Stancor PT Wiring
Tony, I get a little bit of discount from Edcor on all transformers and I can pass that along to you (or anybody from TAG) if you want. They have been terribly slow on deliveries this summer but I love their products. I've been using and selling them for 8 years now and I've only had one that was actually defective...
Do you need the 350-0-350 volts? I know I've got a part # that is 320-0-320 @ 250mA and I can check and see if it is in stock?
Do you need the 350-0-350 volts? I know I've got a part # that is 320-0-320 @ 250mA and I can check and see if it is in stock?
Good, Fast, or Cheap -- Pick two...
http://www.rjguitars.net
http://www.rjaudioresearch.com/
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http://www.rjguitars.net
http://www.rjaudioresearch.com/
http://diyguitaramps.prophpbb.com/
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dorrisant
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Re: Old Stancor PT Wiring
This one needs to be 350-0-350 200mA. It is for a Jim Kelly build... Gotta roast those 6V6s at maximum... 
"Education is what you're left with after you have forgotten what you have learned" - Enzo
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RJ Guitars
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Re: Old Stancor PT Wiring
OK then eBay may be your best friend...
Good, Fast, or Cheap -- Pick two...
http://www.rjguitars.net
http://www.rjaudioresearch.com/
http://diyguitaramps.prophpbb.com/
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http://www.rjaudioresearch.com/
http://diyguitaramps.prophpbb.com/
Re: Old Stancor PT Wiring
Have you thought about an Antek torroid?
This one, with the 2 secondaries parallel: http://www.antekinc.com/as-1t350-100va- ... ansformer/
This one for extra mA: http://www.antekinc.com/as-2t350-200va- ... ansformer/
Or this one with a doubler: http://www.antekinc.com/as-1t250/
With shipping, around $50, maybe a bit less.
There is no 5V winding. There are 2 6.3V windings. You might be able to drop 1.3 with a couple of diodes in the supply, but I'm not sure how that works with a rectifier tube.
This one, with the 2 secondaries parallel: http://www.antekinc.com/as-1t350-100va- ... ansformer/
This one for extra mA: http://www.antekinc.com/as-2t350-200va- ... ansformer/
Or this one with a doubler: http://www.antekinc.com/as-1t250/
With shipping, around $50, maybe a bit less.
There is no 5V winding. There are 2 6.3V windings. You might be able to drop 1.3 with a couple of diodes in the supply, but I'm not sure how that works with a rectifier tube.