Studiomaster Parts ?

[p***@hotmail.com]

Hi,

I've managed to get myself stitched up a treat... I bought a faulty
Studiomaster Powerpack 400 powered mixer off Ebay, in the hope I could
repair it. (The guy described it as "I'm not sure how serious the
fault is, but it wouldn't power up one day when I switched it on".
When I got it, it was obvious that someone had already been poking
around inside as most of the main PCB screws were missing, and lots of
the case screws were gone too.

On further investigation I've established that the fault is a short in
the mains transformer (unrepairable and expensive), and I'm trying to
get a replacement.

I'm not sure how wise this is, as the rest of the board may have taken
a hit when it blew. I've tried the transformer manufacturer (Toroid
International) and they can't help. I can't get through to Gee's in
Liverpool (answerphone, though I'll keep trying). It's a big toroidal
job with secondaries at 21v, 44v and 51v.

Anyone got any ideas where I might get hold of one of these ?

Many thanks,

Kev.

[Phil Allison]

Post by p***@hotmail.com
I've managed to get myself stitched up a treat... I bought a faulty
Studiomaster Powerpack 400 powered mixer off Ebay, in the hope I could
repair it. (The guy described it as "I'm not sure how serious the
fault is, but it wouldn't power up one day when I switched it on".
When I got it, it was obvious that someone had already been poking
around inside as most of the main PCB screws were missing, and lots of
the case screws were gone too.
On further investigation I've established that the fault is a short in

the mains transformer (unrepairable and expensive), and I'm trying to

Post by p***@hotmail.com
get a replacement.
I'm not sure how wise this is, as the rest of the board may have taken
a hit when it blew. I've tried the transformer manufacturer (Toroid
International) and they can't help. I can't get through to Gee's in
Liverpool (answerphone, though I'll keep trying). It's a big toroidal
job with secondaries at 21v, 44v and 51v.
Anyone got any ideas where I might get hold of one of these ?

** There are many firms that custom wind toroidal mains transformers - as
well as selling a stock range. They can make one to match the one you have
if you can *accurately* describe it - or better still, give it to them
to analyse.

Look in the phone book or ask around for the names of the businesses that
do this.



.............. Phil

[Pooh Bear]

Post by p***@hotmail.com

Post by p***@hotmail.com
I've managed to get myself stitched up a treat... I bought a faulty
Studiomaster Powerpack 400 powered mixer off Ebay, in the hope I could
repair it. (The guy described it as "I'm not sure how serious the
fault is, but it wouldn't power up one day when I switched it on".
When I got it, it was obvious that someone had already been poking
around inside as most of the main PCB screws were missing, and lots of
the case screws were gone too.
On further investigation I've established that the fault is a short in

the mains transformer (unrepairable and expensive), and I'm trying to

Post by p***@hotmail.com
get a replacement.
I'm not sure how wise this is, as the rest of the board may have taken
a hit when it blew. I've tried the transformer manufacturer (Toroid
International) and they can't help. I can't get through to Gee's in
Liverpool (answerphone, though I'll keep trying). It's a big toroidal
job with secondaries at 21v, 44v and 51v.
Anyone got any ideas where I might get hold of one of these ?

** There are many firms that custom wind toroidal mains transformers - as
well as selling a stock range. They can make one to match the one you have
if you can *accurately* describe it - or better still, give it to them
to analyse.

Alternatively I can give you the spec !

But seriously, John Gee should be able to help. Keep trying.


Graham

[p***@hotmail.com]

On Thu, 08 Jul 2004 03:47:42 +0100, Pooh Bear

Post by Pooh Bear
Alternatively I can give you the spec !
But seriously, John Gee should be able to help. Keep trying.
Graham

I spoke to John Gee this morning and unfortunately he can't locate the
transformer I'm after :-(

He *did* however wonder whether I really needed the 51v at all (from
the 21v, 44v & 51v secondaries). He thought this was only used to
supply phantom power (which I would have no need for). Would you know
if this is right ? Because, if it is, then locating a transformer
with just two secondaries, one double the other, would be so much
easier than trying to get one with all three.

I got the data sheet for the tranny from Ray Thomson at Toroid
International, and I've emailed it to Avel Lindberg (rewinders) to see
if they can make me a one-off. Though, I'm expecting the price to be
silly, and therefore not an option.

I'm also contemplating rewinding it myself, but as I didn't count the
number of turns as I demolished it, I'm sorta stuck on that one !

Many thanks,

Cheers,

Kev.

[Pooh Bear]

Post by p***@hotmail.com
On Thu, 08 Jul 2004 03:47:42 +0100, Pooh Bear

Post by Pooh Bear
Alternatively I can give you the spec !
But seriously, John Gee should be able to help. Keep trying.
Graham

I spoke to John Gee this morning and unfortunately he can't locate the
transformer I'm after :-(

Slightly puzzled by that. I was under the impression that he could source
most of the parts that our former sub-conractor in India used. I thought
he had indeed sourced some transformers from them in the past.

I'm aware that they continued to make this model for other customers until
quite recently.

If it helps I could probably find the sub-contractors' internal part no.

Post by p***@hotmail.com
He *did* however wonder whether I really needed the 51v at all (from
the 21v, 44v & 51v secondaries). He thought this was only used to
supply phantom power (which I would have no need for). Would you know
if this is right ?

Sadly it's wrong. The 51V supplies the 'high side drive' for the output
stage.

Post by p***@hotmail.com
Because, if it is, then locating a transformer
with just two secondaries, one double the other, would be so much
easier than trying to get one with all three.
I got the data sheet for the tranny from Ray Thomson at Toroid
International, and I've emailed it to Avel Lindberg (rewinders) to see
if they can make me a one-off. Though, I'm expecting the price to be
silly, and therefore not an option.

Quite likely so.

Best bet is to see if there is still any unused stock of this part in
India.

Post by p***@hotmail.com
I'm also contemplating rewinding it myself, but as I didn't count the
number of turns as I demolished it, I'm sorta stuck on that one !

That's very true.


Graham

[p***@hotmail.com]

On Fri, 09 Jul 2004 01:10:42 +0100, Pooh Bear

Post by Pooh Bear

Post by p***@hotmail.com
I spoke to John Gee this morning and unfortunately he can't locate the
transformer I'm after :-(

Slightly puzzled by that. I was under the impression that he could source
most of the parts that our former sub-conractor in India used. I thought
he had indeed sourced some transformers from them in the past.
I'm aware that they continued to make this model for other customers until
quite recently.

Well, I can only go on what the man says ! He did make a comment
about how most of the stock had gone now, and that it's been quite a
few years since they (Studiomaster) folded. He did suggest I try TK
Electronics in Rhyl, which I'm about to do.

I have all the technical details on it from Ray at Toroid
International, who manufactured the one in my unit, so like I said,
I'm hoping I can get it rewound (or do it myself as a last resort *IF*
I can find out the numbers for the turns).

Kev.

[p***@hotmail.com]

He did suggest I try TK Electronics in Rhyl, which I'm about to do.

Sorry - I meant TK MUSIC in Rhyl.

[p***@hotmail.com]

Post by Pooh Bear
Slightly puzzled by that. I was under the impression that he could source
most of the parts that our former sub-conractor in India used.

Graham, You wouldn't have the details of that subcontractor would
you ? You never know, it might be worth my while trying to contact
them myself.

Cheers,

Kev.

[Pooh Bear]

Post by p***@hotmail.com

Post by Pooh Bear
Slightly puzzled by that. I was under the impression that he could source
most of the parts that our former sub-conractor in India used.

Graham, You wouldn't have the details of that subcontractor would
you ? You never know, it might be worth my while trying to contact
them myself.

The company in question is Prosund Products Pvt, Mumbai.

You got the full contact details from this webpage didn't you ?

http://www.escindia.org/p1nopq.html

SHRI PRADEEP AHUJA
PARTNER
PROSOUND PRODUCTS
UNIT # 25,SDF-1, SEEPZ
ANDHERI EAST
MUMBAI 400096
MAHARASHTRA
TEL :[phone]
FAX :[phone]
Items :PROFESSSIONAL AUDIO EQUIPMENTS.


Regds, Graham

[Phildo]

Post by p***@hotmail.com
Hi,
I've managed to get myself stitched up a treat... I bought a faulty
Studiomaster Powerpack 400 powered mixer off Ebay, in the hope I could
repair it.

<snip>

You're in luck. The guy that designed all these boards is a regular and
well-respected poster on here. He'll be along shortly to answer your
questions. Where are you based?

Phildo

[p***@hotmail.com]

Post by Phildo
You're in luck. The guy that designed all these boards is a regular and
well-respected poster on here. He'll be along shortly to answer your
questions. Where are you based?
Phildo

South Wales, UK. I've 'progressed' somewhat insofar that I've located
the fault in the transformer... a short in the primary windings.
However, the primary windings are, sorry.. *were*, inside the
secondaries ! So, in order to get at the fault, I had to destroy the
secondary windings ! All I'm left with now is a lovely big ferrite
toroid former and a mountain of twisted wire :-)

I've managed to get the specs for the tranny from the manufacturers
and I'm currently investigating the possibility of getting it rewound.
If this proves ridiculously expensive, I may have a go at it myself.
Simple work, but soul destroying to do it manually !!

There is always the possibility that when (if) I get a working tranny
and connect it up, that there may be something else blown on the desk.
I'm hoping not, as in theory, the short in the primary would cause the
fuse to blow immediately.

Kev.

[k***@yahoo.com]

Post by p***@hotmail.com
Hi,
I've managed to get myself stitched up a treat... I bought a faulty
Studiomaster Powerpack 400 powered mixer off Ebay, in the hope I could
repair it. (The guy described it as "I'm not sure how serious the
fault is, but it wouldn't power up one day when I switched it on".
When I got it, it was obvious that someone had already been poking
around inside as most of the main PCB screws were missing, and lots of
the case screws were gone too.
On further investigation I've established that the fault is a short in
the mains transformer (unrepairable and expensive), and I'm trying to
get a replacement.
I'm not sure how wise this is, as the rest of the board may have taken
a hit when it blew. I've tried the transformer manufacturer (Toroid
International) and they can't help. I can't get through to Gee's in
Liverpool (answerphone, though I'll keep trying). It's a big toroidal
job with secondaries at 21v, 44v and 51v.
Anyone got any ideas where I might get hold of one of these ?
Many thanks,
Kev.

I have a studiomaster C3x .....I knocked it over and broke one of the maininputs,and help for the quest; "how do i locate parts"

[geoff]

Post by k***@yahoo.com

Post by p***@hotmail.com
Hi,
I've managed to get myself stitched up a treat... I bought a faulty
Studiomaster Powerpack 400 powered mixer off Ebay, in the hope I could
repair it. (The guy described it as "I'm not sure how serious the
fault is, but it wouldn't power up one day when I switched it on".
When I got it, it was obvious that someone had already been poking
around inside as most of the main PCB screws were missing, and lots of
the case screws were gone too.
On further investigation I've established that the fault is a short in
the mains transformer (unrepairable and expensive), and I'm trying to
get a replacement.
I'm not sure how wise this is, as the rest of the board may have taken
a hit when it blew. I've tried the transformer manufacturer (Toroid
International) and they can't help. I can't get through to Gee's in
Liverpool (answerphone, though I'll keep trying). It's a big toroidal
job with secondaries at 21v, 44v and 51v.
Anyone got any ideas where I might get hold of one of these ?
Many thanks,
Kev.

I have a studiomaster C3x .....I knocked it over and broke one of the maininputs,and help for the quest; "how do i locate parts"

Is what you broke an XLR socket ? Try any electronic parts store, or
online RS Components or Digikey or element14 .

geoff