UGS-muse preamp GB

Any idea regarding pricing for a full set?

Carlos, do you have any toshiba dual jfets?

I should be starting my system overhaull this winter, time to start gathering parts! :)

The french guys are asking for the full PCB set, and not only the upgrade PCB.
So there might be all you need.

But if I may give an advice, start first by sourcing the JFETs first (talking about the UGS modules) those criters are the most hard to get, by far.

If you go for matches single JFETs instead of the dual ones, then you should choose the bipolars accordingly, so the cases match. the design uses a dual heatsink so all transistors are at the same temperature. It's not mandatory, but we want the best, aren't we ? ;)

about the price, it's about 50 euros, plus shipping.
Price may change, as the workgroup wants the other PCBs.

Work in progress
 
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Any idea regarding pricing for a full set?

Carlos, do you have any toshiba dual jfets?

I should be starting my system overhaull this winter, time to start gathering parts! :)

...those dual jfets are indeed hard to come by and expensive nowadays.
I remember that the groupbuy we did at the time they were arround 6.5 € each...will be more than that now.

There is a seller in ireland who has them....but at the quoted price.

Mine came all matched and are installed in the modules i have built.

But maybe you should not make such a big thing about it....i remember talking to Papa Erno Boberley at the time , when he still had his shop open, and what he told me over the phone was "..carefull matching of 2SJ74 and 2SK170 and i doubt anyone can tell the diference.".....

And those are still obtainable ( genuine ).

...sorry i can't do more for a countryman ...but unobtanium is ......unobtanium.:(

here is the place :

http://www.donberg.ie/catalogue/2sk_389.html


...brace yourself for the other one:

http://www.donberg.ie/search?query=2sj109
 
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...those dual jfets are indeed hard to come by and expensive nowadays.
I remember that the groupbuy we did at the time they were arround 6.5 € each...will be more than that now.

There is a seller in ireland who has them....but at the quoted price.

Mine came all matched and are installed in the modules i have built.

But maybe you should not make such a big thing about it....i remember talking to Papa Erno Boberley at the time , when he still had his shop open, and what he told me over the phone was "..carefull matching of 2SJ74 and 2SK170 and i doubt anyone can tell the diference.".....

And those are still obtainable ( genuine ).

...sorry i can't do more for a countryman ...but unobtanium is ......unobtanium.:(

here is the place :

Semiconductor: 2SK389 (2SK 389) - BSW-FET 50V / 20mA / 0.4W...


...brace yourself for the other one:

Dönberg Electronics - Search Results: 2SJ109


Well I have 4 matched quads of the single jfets ( 16 total) and 100 2sk170 ( I might buy some more 2sj74 to match) so regarding jfets I'm good.

I guess I'll have to register in the French site to get the boards. :p

Will it be hard to install the software or does it come pre installed? Soldering and case assembly I have no problem with, but the soft side of building is my problem.

Carlos, If I go ahead I might be bothering you with lots of questions in the winter! :)
 
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......

Will it be hard to install the software or does it come pre installed? Soldering and case assembly I have no problem with, but the soft side of building is my problem.

Carlos, If I go ahead I might be bothering you with lots of questions in the winter! :)

No....the hex file has to be programmed into chip after soldering, with a programmer, it´s no big deal really.

As for questions feel free, glad to help....:D and if you nag too much i can always complain to you dad......heheheh

Seriously it will be a pleasure as i will be doing it for the 3rd time ( i built the slim version of the original as well, just like François' prototype )

You wont regret building this i assure you.

C
 
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That japanese shop price seems too good to be true!

I have the single jfets so no problem there.

...actually it's not you can trust those guys.
But as i said shipping is something like 75$ minimum,
and then add 30% ( minimum 50€ ) customs here in our beautiful garden by the sea....
So.....really it's painfull.

:faint:

I would go with single jfets with degeneration ( see EUVL ) , matched as tightly as you can arround 8 mA and you are good to go.
 
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From what I read of the original project features, this new version will be much easier to program that the previous one, using a normal built-in USB port.

Previous project used a supplied JTAG adapter and you needed a LPT port on your computer (I know that mean old computer but that worked)

I'm not expecting the processor to be pre-programmed. You build your controller PCB and then you'll program it. They will distribute the compiled firmware HEX file for upload, and they generally supplied the full code for the adventurous ones. I modified the previous version to change the default messages and settings. That was fun.

They also make sure to post updates, are well responsive of bugs that we can find, and post fix rapidly. This preamp version is an evolution of the previous version and will reuse a large part of the previous proven code.

These designers are always using free development tools and freeware programmer software. They also supplied clear instructions on how to program your board. Me or some other member can always translate their instructions, no big deal. I wouldn't worried if I were you, but keep in mind it is still DIY and hands-on work is to be expected :p