PDA

View Full Version : HELP needed: identifying an output transformer


vencel
08-08-2012, 20:32
Hello,

I would like to ask for your help to identify an output transformer.
Unfortunately I only have one. More or less everything is written on it but I would like to know more about it so in case anybody knowns anything about it I would really appreciate if you could share it with me.
Also I am looking for the same OPT to have a pair.

THANKS!
László

https://dl.dropbox.com/u/22181492/OTH-10/oth10_001.jpg
https://dl.dropbox.com/u/22181492/OTH-10/oth10_002.jpg
https://dl.dropbox.com/u/22181492/OTH-10/oth10_003.jpg
https://dl.dropbox.com/u/22181492/OTH-10/oth10_004.jpg
daytona600
09-08-2012, 05:06
matsushta is the parent company of panasonic
vencel
09-08-2012, 05:14
matsushta is the parent company of panasonic

Thanks for the info. Do you know anything more about this OPT?
What tube could it be designed for?
When could it be manufactured and in what amplifier could it be used?
lurcher
09-08-2012, 07:33
10W 6K primary, I would guess el84 or ecs82, can't see if its push pull or single ended. You could tell with a ohmmeter.
vencel
09-08-2012, 12:43
10W 6K primary, I would guess el84 or ecs82, can't see if its push pull or single ended. You could tell with a ohmmeter.

Can you let me know how to do it?
AndrewR
15-08-2012, 10:49
Check with an ohm meter and see if you can map out the dc resistance between the primary pins. If you can map out a centre tap on the primary (symmetrical resistance between pins on the primary), then it is likely to be push-pull. May also be worth seeing if there are any ultra-linear (feedback) taps as well on the primary.

It looks like P1 and P2 could be the top and bottom of the primary winding. The question is whether B1, B2, SG1, SG2 are taps on that winding.

If it is push-pull it is likely to be good for an EL34, KT88 or 6550.

Andrew
vencel
15-08-2012, 20:00
Check with an ohm meter and see if you can map out the dc resistance between the primary pins. If you can map out a centre tap on the primary (symmetrical resistance between pins on the primary), then it is likely to be push-pull. May also be worth seeing if there are any ultra-linear (feedback) taps as well on the primary.

It looks like P1 and P2 could be the top and bottom of the primary winding. The question is whether B1, B2, SG1, SG2 are taps on that winding.

If it is push-pull it is likely to be good for an EL34, KT88 or 6550.

Andrew

Thanks for the help. I will do so.
Is it normal to use a 10W for PP EL34?
Thanks!
AndrewR
16-08-2012, 09:54
Good catch, I was distracted by the impedance being the usual value for PP EL34. EL34 PP transformers tend to start at 20W minimum. EL84 PP transformers usually have a 8k impedance.

If it turns out to be a single ended transformer, then the power and impedance should suit both the EL84 and EL34 (particularly the EL84).

Andrew