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Old 30th November 2008, 08:01 AM   #51
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Ok,
I didn't want to save money at the cost of a lack in sound quality, so I've order an 2x18v 160 va toroïdal transformer...
Next step is soldering and wiring, and I'll be back here quite often again to get some further advices, and I have to say that I appreciate very much the help provided at this first level of my project
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Old 30th November 2008, 08:30 AM   #52
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Quote:
Originally posted by pacificblue
Excuse me. I have to take my shoes off, because after reading that post, my toenails have rolled themselves up.
Sorry about that horrid oversimplification on my post (49), but if I tried to write a longer explanation, I think it would have been even worse.

Howabout something a bit more accurate?
Just relate these:
transformer is like a loudspeaker, in that both are a coil around a magnet.
power supply is like a crossover, in that both damp certain frequencies.

The power supply design is a given.
The maker has specified a certain transformer that will match.

Result:
A much different transformer would require a much different power supply.
Supporting a smaller (va) transformer would increase the expense of the power supply.

There are so many options available, but a change is unlikely to improve either the simplicity or cost-effectiveness of the kit.
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Old 30th November 2008, 10:36 AM   #53
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And from the chaos a voice spoke to me: "Smile and be happy. It could become worse." And I smiled and was happy. And it became worse.
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Old 30th November 2008, 10:45 AM   #54
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I've missed something I guess...
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Old 30th November 2008, 10:53 AM   #55
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Now really. Where is there a magnet in a transformer?

In a loudspeaker there is no coil around a magnet. There is a coil moving in a magnetic field.

Quote:
Originally posted by danielwritesbac
Supporting a smaller (va) transformer would increase the expense of the power supply.
And decrease the expense of the transformer.

Quote:
Originally posted by danielwritesbac
There are so many options available
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Old 30th November 2008, 10:57 AM   #56
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Quote:
Originally posted by androuski
I've missed something I guess...
Nothing important. Daniel tends to mix things up and then draw conclusions from the mix.
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Old 30th November 2008, 06:55 PM   #57
sneih is offline sneih  Indonesia
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hi, help me please.

anyone have a link about point to point 1875?


thx for the advice
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Old 6th April 2009, 03:04 AM   #58
haziz is offline haziz  United States
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Quote:
Originally posted by Sparky OR
Yes, on the insulator, and don't forget the head of the screw needs to be insulated from the tab on the device also. A nylon "hat" washer with the length trimmed to fit the thickness of the tab.

Newbie alert! In plain English and preferably with a "for Dummies" approach: Once again, how do you insulate the LM1875 from the heatsink while also allowing thermal conduction?

Also any reasonably priced ready made cases available? My hardware/case skills are absolutely pitiful.

Thanks.

Sincerely,

Hany.
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Old 6th April 2009, 06:51 AM   #59
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Quote:
Originally posted by haziz
how do you insulate the LM1875 from the heatsink while also allowing thermal conduction?
With mica or silicone washers. Silicone washers need to be replaced every now and then, therefore mica washers are preferable.

Quote:
Originally posted by haziz
Also any reasonably priced ready made cases available?
What is reasonably priced for you? http://www.hammondmfg.com/scpg.htm
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Old 6th April 2009, 01:09 PM   #60
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Reasonable price for a cabinet, how about getting a sattelite TV converter from the thrift store and reconfigure it, the metal work on the older ones is a nice size, well executed. For example, here is one from a Drake,
[IMG]Click the image to open in full size.[/IMG]
A little drilling, I changed the auxiliary face plate, but hey, only $5!
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