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Help on transformers please

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boywonder

boywonder

Member
Joined 2008
Sgkho249 said:
Hi all, I need help to identify the usage of these transfomers. Is it worth keeping? Thanks
Click to expand...

Yes, they are quite useful, and worth keeping.

The Parmeko "Neptune Series" 6000/71 is a power transformer with selectable 200-250VAC mains and 250V and 350V secondary taps @ 180ma. Assuming that you are in a 230-240VAC country, this would be very useful for a SE amp. It has a 3A 5V winding for tube rectification as well.

The Gresham "inductor" is a 20H choke rated at 70ma. This would be great for a preamp CLC power supply, as the current rating is a little low for a power amp.

The Lux OY-15 appears to be a 3.8K PP output transformer with screen grid taps which is also very useful for a PP amp. The multiple secondary impedances as well as the screen grid taps will allow many possibilities for output tubes. This can operate in Triode, UL, or pentode mode.

Since it appears that you have a single output transformer, you can entertain building a MI amp.

Please confirm that the stamped numbers are "3.8K", they are a little hard to make out in the pic. Roughly how large is this transformer? maybe a picture with a few other common items would be useful, as you'll need to determine/guess the power rating for this one.

Can you post another close up pic of the other Parmeko transformer? The existing pic is too blurry to make out.....
 
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S

Sgkho249

Member
Joined 2011
boywonder said:
Yes, they are quite useful, and worth keeping.

The Parmeko "Neptune Series" 6000/71 is a power transformer with selectable 200-250VAC mains and 250V and 350V secondary taps @ 180ma. Assuming that you are in a 230-240VAC country, this would be very useful for a SE amp. It has a 3A 5V winding for tube rectification as well.
(Thanks, yes im in 230v country.)

The Gresham "inductor" is a 20H choke rated at 70ma. This would be great for a preamp CLC power supply, as the current rating is a little low for a power amp.
(Thanks, whats a CLC power supply.)


The Lux OY-15 appears to be a 3.8K PP output transformer with screen grid taps which is also very useful for a PP amp. The multiple secondary impedances as well as the screen grid taps will allow many possibilities for output tubes. This can operate in Triode, UL, or pentode mode.
(Thanks, heres the pic http://i697.photobucket.com/albums/vv339/sgkho249/DSC_0058.jpg its a 6.6k)


Since it appears that you have a single output transformer, you can entertain building a MI amp.
(Thanks, whats a MI amp,mono intergrated,)

Please confirm that the stamped numbers are "3.8K", they are a little hard to make out in the pic. Roughly how large is this transformer? maybe a picture with a few other common items would be useful, as you'll need to determine/guess the power rating for this one.

Can you post another close up pic of the other Parmeko transformer? The existing pic is too blurry to make out.....
Click to expand...
(Thanks, heres the pics http://i697.photobucket.com/albums/vv339/sgkho249/DSC_0061.jpg. Its a 10H 180ma what can it use for?

The black transformer is without any specs. Its T52-158 A-AS-RLC. What is it use for. http://i697.photobucket.com/albums/vv339/sgkho249/DSC_0057-1.jpg

Thanks again.
 
boywonder

boywonder

Member
Joined 2008
The 10H 180 ma choke would work great in a CLC SE power amp power supply. I imagine that it came off of the same amp as the 180ma power transformer.

If you are looking for a beginner project to use some of this iron and have a circuit board to build on, consider the TubeLab Simple SE. Tubelab George sells the PCBs for about $35 + shipping. This is a cathode biased design using common output and driver tubes. You could use the power transformer and the 10H choke for this no problem. There are lots of other SE designs on the forum here as well.

Since you only have one output transformer, you'll have to pick up a pair to do a stereo SE amp. Consider the Edcor XSE series, very affordable and a great value.

http://www.tubelab.com/Simple_SE.htm

Where are you located?
 
S

Sgkho249

Member
Joined 2011
boywonder said:
No idea on that one....perhaps a google search. Is it from a solid state amp/preamp?

Thanks Troncones! Please feel free to chime in with suggestions......
Click to expand...


Hello boywonder,
Sorry to bring up an old post. i am intending to build a SET poweramp with 2x el3n/ 2x 6j5gt/ ez81 rectifier tube. PT parmeko 350-0-350 CT 0.18amp filement 6.3v 0.5amp. rectifier 5v 3amp, parmeko chock 10H 180mamp.

question is will the amperage be enough for all the tubes, also can i use the rectifier tap of 5v 3amp to run on the ez81.

attach a schematice
1365387973279.jpg


Thanks in advance....
Please be paitent with me as this is the first tube amp im building
 
45

45

Member
Joined 2008
Sgkho249 said:
i am intending to build a SET poweramp with 2x el3n/ 2x 6j5gt/ ez81 rectifier tube. PT parmeko 350-0-350 CT 0.18amp filement 6.3v 0.5amp. rectifier 5v 3amp, parmeko chock 10H 180mamp.

question is will the amperage be enough for all the tubes, also can i use the rectifier tap of 5v 3amp to run on the ez81.



Thanks in advance....
Please be paitent with me as this is the first tube amp im building
Click to expand...

The amperage will be not enough for powering all filaments. You could use a bridge rectifier for the 5V secondary and use it to supply the EL3n filaments. The 6.3V/0.5A could be stretched to power 6J5's however it would be a bit bizzarre using AC for signal tubes and DC for output tubes. Still you would need 6.3 1A for the EZ81. Older types like EZ40 and EZ41 (very similar to EZ80 and 90) were specified with both AC and DC filament supply. However I have never seen this for EZ81.
 
boywonder

boywonder

Member
Joined 2008
You could always use a separate 6.3V filament transformer......

Any particular reason for this circuit?

Your output transformer is PP, this is SE; I imagine that you are planning on buying SE output transformers?

Do you already have EL3n's? Those tubes look like they need some crazy sockets.....
 
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S

Sgkho249

Member
Joined 2011
boywonder said:
You could always use a separate 6.3V filament transformer......
Ok thanks, 6.3v how much amperage should I go for so that it will have enough current to run 2x el3n and 2x 6j5 and rough guide on the price please.

Any particular reason for this circuit?
Really have no ideal but I heard these el3n over at a friends place and I like it. So I thought with the iron I have I could try and build a set amp. Almost done with all the items I needed for these project. And realize that the amperage is only 0.5a not enough to provide for the 4 tubes.
As for the rectifier 5v 3a tap can I use a ez81? I have actually order.a.hytron 6004 and its in the way. Not much info though for the 6004 but its similar to a 5y3 im I right?

Your output transformer is PP, this is SE; I imagine that you are planning on buying SE output transformers?
I have a pair of 7k klangfilm just nice for the el3n


Do you already have EL3n's?
Click to expand...
Yes I have 4pcs of them through a friends.

Hope to have more.infomation before I start doing it....

Thanks
 
S

Sgkho249

Member
Joined 2011
boywonder said:
You could always use a separate 6.3V filament transformer......
Ok thanks, 6.3v how much amperage should I go for so that it will have enough current to run 2x el3n and 2x 6j5 and rough guide on the price please.

Any particular reason for this circuit?
Really have no ideal but I heard these el3n over at a friends place and I like it. So I thought with the iron I have I could try and build a set amp. Almost done with all the items I needed for these project. And realize that the amperage is only 0.5a not enough to provide for the 4 tubes.
As for the rectifier 5v 3a tap can I use a ez81? I have actually order.a.hytron 6004 and its in the way. Not much info though for the 6004 but its similar to a 5y3 im I right?

Your output transformer is PP, this is SE; I imagine that you are planning on buying SE output transformers?
I have a pair of 7k klangfilm just nice for the el3n


Do you already have EL3n's?
Click to expand...
Yes I have 4pcs of them through a friends.

Hope to have more.infomation before I start doing it....

Thanks
 
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