Wanting to borrow - 240V - 240V Isolation Transformer

[adamg]

I have probably with hum generated by the toroidal transformer in my integrated amp.

 

I assumed it was a problem with the transformer however Zaphod has suggested it may be that the unit is reacting to DC.

 

http://www.stereo.net.au/forums/index.php?/topic/53659-replacement-toroidal-transformer/

 

If anyone has an isolation transformer that I can borrow to check ZBs theory that would be appreciated. If it solves the problem then I would be in the market to buy.

 

Alternatively I'm happy to return the unit with a token of my appreciation.

 

I live on the Sth Gold Coast but if postage is required all costs will be covered by me obviously.

 

Thanks Adam

Edited May 27, 2013 by adamg

[TP1]

From my own experience Toroidal transformer buzzing  has been caused by DC in the circuit.  However, this type of buzzing is not usually the same all the time and it often disappears completely ( usually when no one else is home switching on appliances) . Is yours constant or does it vary?

 

There are also other alternatives such  as a DC offset blocking device as per this link. If you know anyone who can build it it could solve your problem ( if it is indeed caused by DC). I  wonder why all audio gear doesn't have this feature anyway?

 

http://sound.westhost.com/articles/xfmr-dc.htm

Edited May 27, 2013 by Tasso

[adamg]

From my own experience Toroidal transformer buzzing  has been caused by DC in the circuit.  However, this type of buzzing is not usually the same all the time and it often disappears completely ( usually when no one else is home switching on appliances) . Is yours constant or does it vary?

 

There is a base level that the noise never falls below, but there is small variations in level, then more obvious but infrequent surges to a louder level for say 5 - 10 minutes. It could be that I don't pick up all surges depending whether I'm conscious of it, other noise around, etc.

 

There is no obvious link to other activity on the mains but I haven't focused on this possibility.

 

Thing is that the noise wasn't there when I started using the amp and there hasn't been any changes in the house that I can think of.

Edited May 27, 2013 by adamg

[LogicprObe]

Doesn't necessarily have to be from within your house.

Could be down the street.