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PostPosted: Sat Jun 25, 2011 12:00 am
by janneman01
Sorry I do not understand your question and what you mean by 'reflected'.
From the article you can see that the amplifier has 1 PCB for 1 channel (mono) so for stereo you need 2 amplifier PCBs.
The protection system has also 1 PCB for one channel, for stereo you need 2.
So in total for stereo you need 4 PCBs.

jan didden

PostPosted: Sun Jun 26, 2011 12:00 am
by pat75
dear jan,
here is these pcb

PostPosted: Sun Jun 26, 2011 12:00 am
by janneman01
This is a double-sided PCB.

jan didden

PostPosted: Sun Jun 26, 2011 12:00 am
by kioseusznook
Hi Jan,

Your comment re a new design of protection board has got me piqued as I had recently noticed that U2 is incredibly hard to source. In fact after extensive searching I failed to locate a supplier anywhere. Does this issue have any bearing on the new design, and if so will you issue it to elektor so that those like me who purchased the article can download it? Thanks.

Robbie.

PostPosted: Sat Nov 12, 2011 12:00 am
by linn-fan
Dear Jan and all,

I build up your PAX-amp. During test the transistors of the voltage amplifier are getting quite hot on both channels. When estimating the power loss I got around 300mW which can explain the heating. Is it really safe to run the amp at this temperature or is it better to add a cooling to the transistors?

Thank you for answers

PostPosted: Sun Nov 13, 2011 12:00 am
by linn-fan
Does any one who has build the PAX-amp made the same observation as me that the six transistors of the voltage amplifier are getting quite hot?

PostPosted: Mon Nov 14, 2011 12:00 am
by mick.carrick
Hi

Yes they do get hot and I believe Jan has comments on this on his Linear Audio website. I think he specified the higher power version (TO220) in the AudioXPress article. Jan says they have caused no problems running hot and that has been my experience also.

Enjoy the amps.

Mick

PostPosted: Mon Nov 14, 2011 12:00 am
by linn-fan
Thanks Mick that helps me to be sure everything is o.k. )

PostPosted: Thu Nov 17, 2011 12:00 am
by linn-fan
which replacement transistors with TO-220 case does Jan use for the voltage amp in this article. I can't find any hints on his homepage.

Thanks for answering

PostPosted: Sat Nov 19, 2011 12:00 am
by mick.carrick
Finally dug it up!

The higher power (TO126) transistors were specified as:
2SA1209 and 2SC2911.

Good luck

Mick