The diyAudio First Watt M2x

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#4,481
pfarrell said:
... IPS6—"virtually indistinguishable" from Norwood in my system—and no SMD—I thought Mark Johnson was being funny—until he confirmed to me that he gave them the secret sauce too. 😀
Click to expand...

Somewhat the same experience here! But push comes to shove, I will take the Norwood (personal preference).

In my system, I prefer IPS7, Norwood, Austin, and of course Ishikawa. Tucson is nice too but I have it in semi-retirement as well as my IPS6, and Mountain View. My Cedarburg is not yet built, but I have the cards and the parts for a pair to be assembled just sitting in my drawer with the semi-retired boards. I will try it eventually but I do not have the motivation yet listening to IPS7 at the moment. Thanks again to Mark Johnson for these wonderful sounding cards.
 
#4,485
Halted was at the corner of Lawrence Expressway and Central Expressway; that's one of those places where the civil engineering geniuses decided that cloverleaf exit roads can pretend to be city streets. So it was called "Ryder Street" but in fact it was the southeast cloverleaf.

There was a surplus electronics store (smelly dump) called Weird Stuff Warehouse on Caribbean Drive, but it was halfway between Mathilda and Fair Oaks.
 
#4,486
Second build of IPS6 today, and I noticed something strange. I have completed the boards, with newly matched Fets, and noticed that my J113 transistors are backwards from all the other pictures in this thread. I carefully printed out the ON Semi Data sheet to pick the GSD pins on the transistors. I quadruple checked this. THEN, I put one of the non matched transistors on the transistor checker, and it shows G and D reversed from the diagram. Most likely why my first build never worked. As I now don't trust the matching of the first set of J113s, I will see how hard it will be to reverse these 4 transistors in these, now finished, boards.

J113 ordered from Mouser, I was astonished to find the data sheet wrong. I guess those of you in the profession find this to occur from time to time.
 
#4,491
Bones13 said:
... noticed that my J113 transistors are backwards from all the other pictures in this thread. I carefully printed out the ON Semi Data sheet to pick the GSD pins on the transistors ...
Click to expand...

I printed the ON Semiconductor datasheet just now, and discovered that it is indeed wrong (!!). ON Semiconductor shows G-S-D from left to right on the flat ("front") side of the TO-92 package, BUT THAT IS WRONG. Viewed from the flat ("front") side of the package, J113's pins are D-S-G from left to right.

I am so sorry you got screwed by this mistake!! It's not your fault (Good Will Hunting).

It is a bit of a mystery, how you managed to perform the JFET matching operation when working from the wrong pinout??

Two lucky events worked in your favor: (1) you studied the photos of other people's boards and noticed a discrepancy; (2) you plugged some J113s into a Mega328 component tester and noticed that it displayed an unexpected pinout. These stopped you in your tracks and prevented further misery from additional dead boards.

Please delete the erroneous ON Semiconductor .pdf datasheet from all of your hard drives, and replace it with the correct Fairchild datasheet attached below.

Also please check your Private Messages.

_
 

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#4,500
Gotta give credit to Mouser. I was just on the phone with them for another reason and asked how I could properly let them know about the data sheet. I am not sure if this applies to other suppliers.

I've submitted it.

For anyone else that happens to run into something like this:

1) Click on part link in Mouser.
2) Upper right hand corner button that says "see an error"

Self explanatory from there.

Thanks to Bones!!!!
 
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