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Potential EUVL F5X designed case user distribution check

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US case buyers who are anxious to get theirs hands on the case, please email me via the forum. I am more than happy to ship the case now.

From Mark, one of the cases has option 1, I will have to check whether there is any marking on the box of such option, if not, I will have to open them until I find this box. Also, custom may come later from DHL, I am assure that you will know when I get the bill :)

Anyhow, 2012 is off a good start for us!!
 
Have not heard from smyslow.
But I know he has been extremely busy.

You have all waited over a year.
A couple of days is not so unbearable.
Else you can always drive to Austria to pick up personally. ;)

And you cannot build till the heatsinks are also there.
The distributors might want to send with the sinks and not separately.

So patience. :)


Patrick
 
Just received a email from smyslow which says :

Hi all,

good news! Our cases arrived today, in total 14 boxes.
I'll keep all the stuff until the heatsinks arrive, hope this is OK for all of you.
More infos and maybe some pictures at Sunday.

Many thanks to Mark and Patrick!

Kind regards,
Uwe


Nearly all of our tasks have been fulfilled.
Just Mark's heat sink tests for the regulator not yet completed but under way.

;)


Patrick
 
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Hey Fred, I think I might be a little bit confused. Do you have the heatsink from Conrad as well? For some reason I was thinking they had not shipped yet.

Thanks
Hee hee, it was more like a joke to whoever can't wait to see the workmanship of the case kit ;) It probably makes more sense to wait for the Conrad and ship together to save a few bucks. Of course, you and Toufu can come to pick the boxes up if you guys want to as well. The boxes are living in my wagon's trunk for the moment :D
 
There is a packing list inside the carton.
The packing list also gives you hinds on the construction of the case.
I'm preparing a "sketch book" for case assembly. I hope this can help a little bit.
I won't go into detail of any wiring as this is a some kind of an art and also the fun of DIY for your creation. Also, wiring is something for discussion on the forum.
Again, thanks for the distributors.
Cheers!
Mark
 
I thought you might be interested in our experience with ZhouFang's matched devices.
The following is only meant to be a reference point for you all.
So I try to be as neutral as possible and only reveal facts.

Further to AndrewT's post earlier about matching accuracy of ZhouFang :

http://www.diyaudio.com/forums/grou...e-user-distribution-check-16.html#post2891458

We earlier bought a total of 20 pairs of 2SK1530/2SJ201 from him at premium price.
They were supposed to be PPNN matches.
On Andrew's advice of his findings, we repeated the test ourselves.
The test is exactly the same as Zhou uses, namely gate tied to drain and passing 2A constant current.
Temperature is at room temperature.
But we use computer matching, so the time that the device is under current is the same for all measurement samples.
And we took 5 consecutive readings and only averaged the middle three.

The results are :

2SK1530 Vgs = 2.34~2.43V
2SJ201 Vgs = -2.37~-2.39V

The figures do not exactly agree with those measured by Zhou, which suggested a much better match.
However I do honestly think though that Zhou did not meant to deceive.
It is not in his own interest to.
And they are still better than random FETs with no match.
Whether they are worth the asking price is another story.

We shall curve trace them at operating conditions later on when we have time.
But this is quite time consuming, so it won't be a while.


Patrick
 
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Hi Patrick,

I kind of suspect that Zhou didn't have a consistently controlled environment while he was matching.

Just curious, based on your experience, if the FETS don't match in this simple matching procedure, what will be the probability that they will end up matching in the real condition? Or, maybe I should rephrase - is there any co-relationship between the matching results from such simple procedure (tie D-G) and, let say, with a curve tracer.

Thanks!!
 
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