Toroidal transformer in a Laney LV300H 'She's a smokin'

[MARSHALL BUSTER]

Hi all
As you can guess i have a Laney LV300 head, and upon pluging it in the last time....SMOKE!!
After opening it, it was plane to see the toroidal mains transformer has somehow burned out melting all the plastic wraping.
I have called Laney but they don't want to know since im not a 'sparkie', so i cant order the proper one for it. Now im not a rude person but how shit is that for service? and even if i can buy it, it would take 12-15 weeks as its not in stock. I didn't ask for the price!!!.

Anyway i'v taken on the task of trying to find one like it. Before i go any further here are the details of the toroide i need as they apear on the label....

003----2062B
In: 230V 50/60Hz
Out: 33.5V---0---33.5V
(Ora----Blk----Blue)
0---8V/Blue---blue
0---12V / 0---200V
(Gry--Gry Red---Red)

Now i did buy a new trani and it arived today, but its not got enough wires and the details are as follows...
H0200-162f(P042M)225VA
Pri:0-240V 50-60Hz(Brn,Blu.)133Deg C
Sec:0----35V-3.21A(Red Yel) Ta:35Deg C
0----35V-3.21A(Blk Gry)

Ok thats it realy, you can see the problem i have is i can't find a transformer with all the outputs i need SO!!

Question 1. please can you guys tell me what you think my options are with this amp

2. Is there a way i can get this new trani to work with my amp

3. What other ideas have you got for a DIY job on the amp

Its strange!! in my time as a pro DIYer i have performed many many repairs to boards and components, but never for some reason power suplies!!. Its not rocket sience but it stoped me this time hahaha.
Hope someone can help!!
Thankx

[Steve Conner]

I think your best bet is to add another couple of small transformers, to produce the 12, 8 and 200V supplies.

You may have to connect a couple back to back if you can't find one with a 200V output.

[MARSHALL BUSTER]

Thanks Steve
Yeah the thought did cross my mind! i just wasnt shure if it would get messy and if heat may start being a problem???
Thanks for your reply

[Mars Amp Repair]

if you connect a couple of transformers in series, be careful to get the phasing correct...glen

[jmaf]

Hi all
As you can guess i have a Laney LV300 head, and upon pluging it in the last time....SMOKE!!
After opening it, it was plane to see the toroidal mains transformer has somehow burned out melting all the plastic wraping.
I have called Laney but they don't want to know since im not a 'sparkie', so i cant order the proper one for it. Now im not a rude person but how shit is that for service? and even if i can buy it, it would take 12-15 weeks as its not in stock. I didn't ask for the price!!!.

I believe Laney bought their trafos from SKOT, which I searched now and has been bought by FT Transformers ( FT Transformers Ltd | SKOT Transformers | Bespoke Transformers ). If you've got the reference nr., maybe they'll sell it to you direct? Have a phone chat with them, who knows.

Another option would be to search for a transformer winder in your town. Unwind the burned coil and take the toroidal core over to them and ask for the specs you posted. I live in a tiny non-industrial town and there are no toroid winders here, but I know some I can mail the core to and they'll return it.... Just an idea.

[Steve Conner]

Well, if you're in the UK, I've been recommended a place called Tiger Toroids.
Tiger Toroids

Maybe if you sent them the crispy remains of the old one, they could make you a replacement. I don't know what their minimum order is, a lot of custom transformer places want you to buy 10.

If you do, please check the amp circuitry to make sure nothing is shorted in there and it doesn't just burn out the new one. A transformer like this, high powered but with low powered auxiliary windings, is a burnout waiting to happen in some respects. If one of the small windings gets shorted, it won't blow the primary fuse. Each winding should really have its own fuse.

[MARSHALL BUSTER]

:-)

Thankyou very much everyone, im going to investigate all the sugestions you have given me and will post my results as i have em.
Thanks again