| Author |
Message |
spoke
Guest
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 Posted:
Sun Sep 04, 2005 8:39 pm Post subject:
Main Transformer for MA-25 out of order :( |
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hello,
i've a big trouble with one of my MA-25, the main transformer smoke!!
i would like a new one, or NOS but where can i buy it?
where is Woodside Electronics?
i'm in France.
thanx,
best regards,
didier
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Sander deWaal
Guest
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| Posted:
Sun Sep 04, 2005 9:04 pm Post subject:
Re: Main Transformer for MA-25 out of order :( |
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"spoke" <spoke04@infonie.fr> said:
| Quote: | hello,
i've a big trouble with one of my MA-25, the main transformer smoke!!
i would like a new one, or NOS but where can i buy it?
where is Woodside Electronics?
i'm in France.
|
FWIW, I have a STA-15 mains transformer lying around.
I don't know if that's of any use to you, but in case you're
interested, just reply via e-mail: ln.oodanaw@iwas in reverse order.
BTW. you'd have to find out *why* the mains tranny cooked in the first
place, before replacing it!
--
"Audio as a serious hobby is going down the tubes."
- Howard Ferstler, 25/4/2005 |
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Jon Yaeger
Guest
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| Posted:
Sun Sep 04, 2005 9:19 pm Post subject:
Re: Main Transformer for MA-25 out of order :( |
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in article 1125848374.385695.157700@g43g2000cwa.googlegroups.com, spoke at
spoke04@infonie.fr wrote on 9/4/05 11:39 AM:
| Quote: | hello,
i've a big trouble with one of my MA-25, the main transformer smoke!!
i would like a new one, or NOS but where can i buy it?
where is Woodside Electronics?
i'm in France.
thanx,
best regards,
didier
|
If this is what you have:
http://www.angelfire.com/vt/audio/masco.html
A replacement surplus / vintage transformer ought to be easy to find. The
5V4 drops about 25V and your filter cap is rated at 450V. A 325-0-325
transformer would be optimum.
Alternately, you could use a Hammond 373X or 373BX (700VCT) along with a 5R4
rectifier, which has about a 67V drop across it, giving you a B+ of about
425. That model is "universal" and will accommodate US or European mains
voltages.
Jon |
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Sander deWaal
Guest
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| Posted:
Sun Sep 04, 2005 9:31 pm Post subject:
Re: Main Transformer for MA-25 out of order :( |
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Jon Yaeger <jono_1@bellsouth.net> said:
I think the OP was talking about a Radford MA25 monoblock.
I'd be surprised to find a Masco amp on the European continent :-)
--
"Audio as a serious hobby is going down the tubes."
- Howard Ferstler, 25/4/2005 |
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Jon Yaeger
Guest
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| Posted:
Sun Sep 04, 2005 9:50 pm Post subject:
Re: Main Transformer for MA-25 out of order :( |
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in article 1a8mh19krcl10fq6dhun5bhd4j37taane5@4ax.com, Sander deWaal at
nospam@wanadoo.nl wrote on 9/4/05 12:31 PM:
| Quote: | Jon Yaeger <jono_1@bellsouth.net> said:
If this is what you have:
http://www.angelfire.com/vt/audio/masco.html
I think the OP was talking about a Radford MA25 monoblock.
I'd be surprised to find a Masco amp on the European continent :-)
|
Thanks, Sander. It always helps when folks provide useful info like the
name of the manufacturer! Oh well, time wasted . . . .
Jon |
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François Yves Le Gal
Guest
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| Posted:
Sun Sep 04, 2005 9:52 pm Post subject:
Re: Main Transformer for MA-25 out of order :( |
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On 4 Sep 2005 08:39:34 -0700, "spoke" <spoke04@infonie.fr> wrote:
| Quote: | i've a big trouble with one of my MA-25, the main transformer smoke!!
i would like a new one, or NOS but where can i buy it?
|
Ask Sowter. They should be able to supply a replacement.
http://www.sowter.co.uk/
OTOH, if you're using vintage iron, you could consider having your tranny
rewinded (repaired).
| Quote: | where is Woodside Electronics?
|
Gone south. |
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François Yves Le Gal
Guest
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| Posted:
Sun Sep 04, 2005 10:50 pm Post subject:
Re: Main Transformer for MA-25 out of order :( |
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On Sun, 04 Sep 2005 12:19:25 -0400, Jon Yaeger <jono_1@bellsouth.net> wrote:
| Quote: | If this is what you have:
|
More like a Radford MA-25. |
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spoke
Guest
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| Posted:
Wed Sep 07, 2005 9:54 pm Post subject:
Re: Main Transformer for MA-25 out of order :( |
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François Yves Le Gal wrote:
| Quote: | On 4 Sep 2005 08:39:34 -0700, "spoke" <spoke04@infonie.fr> wrote:
i've a big trouble with one of my MA-25, the main transformer smoke!!
i would like a new one, or NOS but where can i buy it?
Ask Sowter. They should be able to supply a replacement.
http://www.sowter.co.uk/
OTOH, if you're using vintage iron, you could consider having your tranny
rewinded (repaired).
where is Woodside Electronics?
Gone south.
|
bonjour FYL,
j'ai essayé Sowter, mais ils n'ont pas ce modele; je viens de demander
a ABL Transfo, une societe française de me faire un modele sur mesure.
que veut dire "gone south" ?
cordialement,
didier |
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spoke
Guest
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| Posted:
Wed Sep 07, 2005 10:12 pm Post subject:
Re: Main Transformer for MA-25 out of order :( |
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thank you Sander for you proposition, but it's not the same transformer
on the STA15.
"you'd have to find out *why* the mains tranny cooked in the first
place, before replacing it!"
shure, i find, but maybe the "canicule" heat wave.
best regards,
didier |
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didier
Guest
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| Posted:
Wed Sep 07, 2005 10:20 pm Post subject:
Re: Main Transformer for MA-25 out of order :( |
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hello Jon,
it's a Radford MA-25.
http://www.arthurradford.co.uk/
i don't know Masco.
didier
"Jon Yaeger" <jono_1@bellsouth.net> a écrit dans le message de news:
BF4096CD.322AB%jono_1@bellsouth.net...
| Quote: | in article 1125848374.385695.157700@g43g2000cwa.googlegroups.com, spoke at
spoke04@infonie.fr wrote on 9/4/05 11:39 AM:
hello,
i've a big trouble with one of my MA-25, the main transformer smoke!!
i would like a new one, or NOS but where can i buy it?
where is Woodside Electronics?
i'm in France.
thanx,
best regards,
didier
If this is what you have:
http://www.angelfire.com/vt/audio/masco.html
A replacement surplus / vintage transformer ought to be easy to find. The
5V4 drops about 25V and your filter cap is rated at 450V. A 325-0-325
transformer would be optimum.
Alternately, you could use a Hammond 373X or 373BX (700VCT) along with a
5R4
rectifier, which has about a 67V drop across it, giving you a B+ of about
425. That model is "universal" and will accommodate US or European mains
voltages.
Jon
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| Back to top |
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François Yves Le Gal
Guest
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| Posted:
Wed Sep 07, 2005 10:37 pm Post subject:
Re: Main Transformer for MA-25 out of order :( |
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On 7 Sep 2005 09:54:47 -0700, "spoke" <spoke04@infonie.fr> wrote:
| Quote: | j'ai essayé Sowter, mais ils n'ont pas ce modele; je viens de demander
a ABL Transfo, une societe française de me faire un modele sur mesure.
|
Normalement le T2093 Sowter ou un de ses dérivés est OK, sinon ils peuvent
faire du sur mesure.
| Quote: | que veut dire "gone south" ?
|
Société disparue. |
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didier
Guest
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| Posted:
Wed Sep 07, 2005 10:54 pm Post subject:
Re: Main Transformer for MA-25 out of order :( |
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helas, non
j'ai besoin de 2x 380V en HT et 5V pour la valve GZ34, et voici les caracteristiques de 2093:
MAINS T2093 (STA25)
2 x 110 120V to 350 V @ 400 mA, 120V @ 50 mA, 6.3 V CT @ 4 A, 6.3 V CT @ 4 A, 6.3 V @ 2 A Fully shrouded
quel est votre systeme actuellement ?
vous avez eu des LS3/5a, je crois ?
didier
"François Yves Le Gal" <flegal@aingeal.com> a écrit dans le message de news: c59uh19q6dkjli1qp5q4aej3c0ir7gap4r@4ax.com...
| Quote: | On 7 Sep 2005 09:54:47 -0700, "spoke" <spoke04@infonie.fr> wrote:
j'ai essayé Sowter, mais ils n'ont pas ce modele; je viens de demander
a ABL Transfo, une societe française de me faire un modele sur mesure.
Normalement le T2093 Sowter ou un de ses dérivés est OK, sinon ils peuvent
faire du sur mesure.
que veut dire "gone south" ?
Société disparue.
|
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François Yves Le Gal
Guest
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| Posted:
Wed Sep 07, 2005 11:19 pm Post subject:
Re: Main Transformer for MA-25 out of order :( |
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On 7 Sep 2005 10:12:43 -0700, "spoke" <spoke04@infonie.fr> wrote:
| Quote: | thank you Sander for you proposition, but it's not the same transformer
on the STA15.
|
The MA-25 is basically a mono version of the STA-25. The power supply is
very close - check the schematics for instance at
http://www.drtube.com/schematics/radford/sta25.gif - an using a T2093/U
instead of a T2110/U will only result in slightly hogehr HT voltage. |
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Sander deWaal
Guest
|
| Posted:
Wed Sep 07, 2005 11:53 pm Post subject:
Re: Main Transformer for MA-25 out of order :( |
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François Yves Le Gal <flegal@aingeal.com> said:
| Quote: | thank you Sander for you proposition, but it's not the same transformer
on the STA15.
The MA-25 is basically a mono version of the STA-25. The power supply is
very close - check the schematics for instance at
http://www.drtube.com/schematics/radford/sta25.gif - an using a T2093/U
instead of a T2110/U will only result in slightly hogehr HT voltage.
|
To Didier:
I got confused and looked up the specs of my transformer.
It's very possible that it stems from a STA25 after all, it was
salvaged from a PP EL34 amp.
There is a 5 V filament winding for the GZ34, and the HV windings are
indeed about 380 volts (separate, with CT).
It used to supply close to 250 mA for a KT88 PP stereo amp, without
getting too hot :-)
Here's a link to a picture:
http://img109.imageshack.us/img109/8898/radfordpt8zs.jpg
I don't think your old transformer dies because of just a heat wave in
summer, there must be more wrong than just that.
Check the GZ34 and the power supply capacitors, also of the other
channel to prevent it from happening again.
--
"Audio as a serious hobby is going down the tubes."
- Howard Ferstler, 25/4/2005 |
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didier
Guest
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| Posted:
Thu Sep 08, 2005 1:01 am Post subject:
Re: Main Transformer for MA-25 out of order :( |
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i have changed all the tubes, and the problem is always here.
i tested with only the primary 220V, smoke again!
schema & power Supply:
http://didou73.chez.tiscali.fr/images/hifi/ma25_sch.jpg
http://didou73.chez.tiscali.fr/images/hifi/ma25_alim.jpg
the ref. is T2062
http://didou73.chez.tiscali.fr/images/hifi/transfo_alim.JPG
C13, 14 are new.
http://img238.echo.cx/my.php?image=p41200082ct.jpg
http://didou73.chez.tiscali.fr/images/hifi/composant.jpg
didier
"Sander deWaal" <nospam@wanadoo.nl> a écrit dans le message de news:
cdduh1d2idctjct23v4ejp9q5qr8bmb5o2@4ax.com...
| Quote: | François Yves Le Gal <flegal@aingeal.com> said:
thank you Sander for you proposition, but it's not the same transformer
on the STA15.
The MA-25 is basically a mono version of the STA-25. The power supply is
very close - check the schematics for instance at
http://www.drtube.com/schematics/radford/sta25.gif - an using a T2093/U
instead of a T2110/U will only result in slightly hogehr HT voltage.
To Didier:
I got confused and looked up the specs of my transformer.
It's very possible that it stems from a STA25 after all, it was
salvaged from a PP EL34 amp.
There is a 5 V filament winding for the GZ34, and the HV windings are
indeed about 380 volts (separate, with CT).
It used to supply close to 250 mA for a KT88 PP stereo amp, without
getting too hot :-)
Here's a link to a picture:
http://img109.imageshack.us/img109/8898/radfordpt8zs.jpg
I don't think your old transformer dies because of just a heat wave in
summer, there must be more wrong than just that.
Check the GZ34 and the power supply capacitors, also of the other
channel to prevent it from happening again.
--
"Audio as a serious hobby is going down the tubes."
- Howard Ferstler, 25/4/2005 |
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