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MyRef_C with Ultimate BOM

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ClaveFremen

ClaveFremen

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Joined 2005
inserra.it
Paid Member
regiregi22 said:
Thanks for that, Dario. I knew it had something to do with a famous trafo brand (Amveco)
Click to expand...

You're welcome Regi :)

I was thinking about that simple shunt for the LM318 PS (From the TI TL431 datasheet) :scratch1:

Also TP used TL431 and transistors for the Sympatico...

And I suspect that also the MyRef Evolution uses a similar approach (TL471 + transistor + CCS)
 

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udailey

Member
Joined 2008
picasaweb.google.com/udailey/MyRef#
I ordered the BC546 and 639 as well as relay and LM318 from OnlineComponents. Please everyone avoid them at all costs. Its a waste of time and terrible customer service. The order was April 14th after finding other distributors out of stock on LM318 and relay. Others prices were higher than I wanted to pay. OnlineComponents said it would take 10 days to gather them all and then ship but pricing was good on all 4 parts. I have been arguing with them since the Monday before last. Finally I have a shipment but it only has 4 LM318.. WTF!? They didnt even mention it. I also asked them to cover part of the cost for shipping and to ship faster. They obliged and then charged me for the faster shipping. Finally I have shipping confirmation from them.
UPS: Tracking Information
I had to go to Avnet to get the LM318 yesterday. So anyway, let it be known that good pricing is no indication of good service.
Uriah
 
G

geoffcooper

Member
Joined 2006
Tidier schematic?

I found that the schematic that is published for the RevC had some areas where the information was very cluttered - text was jumbled over text. Also the labels for C7 were in the wrong place. I decided to import the pdf into an illustration package, which then allowed me to move things around.

What I think is a tidier version (using existing colours) is attached. I have also produced it in black and white, for those who would prefer it that way, and also attached that.

I hope some find this to be of help.

Regards
Geoff
 

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ppcblaster

Member
Joined 2006
Which chip Lm3886t / Lm3886tf ?

Just wondering which chip is in the kit, do we have a chioce?

I looked at chipamp.com and he uses the insulated Lm3886TF and I used a Russ

Boss heatsink on my chipamp build, about 6"x6" I cut it in half with a hacksaw to 6" long 3" high and never had a problem keeping the chip cool.

I could use some input on heatsink size,

another post suggested "22 square inches of surface area for the LM3886T and For the LM3886TF you have to increase the surface area very substantially."

It says "Determining Surface area of a heatsink is very easy with this nomograph"

Well not for me if someone would explain this it would help.

Thanks
 

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regiregi22

regiregi22

Member
Joined 2009
haciendodelpunkunaamenaza.blogspot.com
udailey said:
UPS: Tracking Information
Click to expand...
You got 'em!

Very thank you geoffcooper for that hard work. The original one was REALLY messy. When I get home, I will update the MyRef_C Documentation file and upload it.

ppcblaster, If we were some moths ago, you could ask National for some samples. But they told me some moths ago that the LM3886 is not now in the free samples program. What a pity! I really loved to "sample" them (for my home-based Research & Development department) :D
 
M

madisonears

Member
Joined 2007
That seems just a bit harsh. In Mauro's defense (and forgive me for speaking for him), he was justifiably proud of an "original" design that he had painstakingly developed to sound good and be simple to build and operate with stability. Let's not overlook the language barrier and cultural differences. While it was perhaps unreasonable of him to not expect some suggestions and criticism, I think there were some know-it-all's who piled on pretty heavy without even understanding the basic operation of the circuit or how good it sounded, and Mauro found that he had to persistently explain and defend his design, without being fluent in English. I can certainly understand his frustration. Those who took the time to build it quickly realized how much better it was than the same old basic chipamp with a few simple circuitry refinements or part swaps that seem to be endlessly discussed here. One person went so far as to offer an "improved" version for sale, WITHOUT MAURO'S PERMISSION. Russ White was the class act who recognized the potential of the design and commercialized it, yet even he couldn't resist tinkering with additional bypass caps. The amp sounds better without them.

For the simplicity of the design, this amp sounds amazingly good. You can modify or complicate it with additional circuitry, as Mauro himself has done, and perhaps get even better sound.

Peace,
Tom E
 
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