Another Discrete Amp - GainBloak

[Svart]

yeah feedback is somewhere between 10k-18k, I settled on 15k. 15pf could easily come from your layout and axial parts..

 

[somnium7]

Just poking around for FET sources and found the 2SK170 at Newark.

http://www.newark.com/38C0227/supplier-direct-ship/product.us0?sku=MCM-2SK170&_requestid=155808

89 cents each...

The rest of the active devices are carried by Newark also.

 

[electronick]

Hi, everyone, I'm looking everywhere for the list of BLOAK schematics shown below, and every link I've found for them appears to be dead. Can someone please tell me where I can find them?

Thanks very much.
-Erik

[quote author="Svart"]SMOKE! ...turns out the schematic doesn't match the numbers on the boards.
on the schematic D1 is really D3 on the board, D2 is really D4, D3/4 is really D1, and D5/6 are really D2.
turns out the biasing for Q5 was screwed up because of this so a few parts changes should get these boards working again.
:thumb:

Aaaah! I am really sorry about the mistake in the drawings. I will replace the lost boards for you.
Originally the drawings were in Orcad. Then I switched to Rimu, redrawn the schematics and created this problem. Also, I used the GainBloak as a template just to make sure all the drawings had that error.  

These should be correct:
GainBloak
FetBloak
Improved FetBloak
BigBloak

Cheers,
Tamas

PS.: I had to delete some files from my web site to make room for these. Some old schematics in my old posts may no longer show.
[/quote]

These don't work either:


Direct links to the latest versions:
GainBloak: http://mysite.verizon.net/res75okq/sitebuildercontent/sitebuilderfiles/gainbloak_v2.pdf
FetBloak: http://mysite.verizon.net/res75okq/sitebuildercontent/sitebuilderfiles/fetbloak_v2.pdf
Improved FetBloak: http://mysite.verizon.net/res75okq/sitebuildercontent/sitebuilderfiles/improvedfetbloak_v2.pdf
BigBloak: http://mysite.verizon.net/res75okq/sitebuildercontent/sitebuilderfiles/bigbloak_v2.pdf

 

[skipwave]

Gain Bloke

Big FET Bloke

Email Tamas to buy some nice little PCBs.

 

[electronick]

Thanks Skipster, I appreciate it.
The names are slightly different from those posted above,
GainBloak
FetBloak
Improved FetBloak
BigBloak

What is the difference (if any) from the two you posted and the ones above? Where can I find schematics of the differences?

Thanks, I do definitely want PCBs from Tamas as soon as I can compare them all.

-Erik

 

[skipwave]

The difference is that I spelled Bloke correctly.  ;D

http://www.urbandictionary.com/define.php?page=3&term=bloke

The first doc I posted is the same as the original GainBloak. The second I posted is the Improved FETBloak.

 

[Svart]

I recommend you jump straight to the Big FETbloke.  That thing is absurd it's so cool.

 

[tonedude]

Going to build my own Bloaks on breadboard using this schematic http://skipwave.net/images/bigfetbloak_v2.pdf and are about to source parts:

BC560 and 550 are easy to find at my favorite swedish dealer (electrokit...) but...

Is it possible to use:
- MJE340/350 as substitutes for MJE800/700  (http://www.fairchildsemi.com/ds/MJ/MJE350.pdf)
- 2SK170GR as subs for 2SK170BL  (http://datasheet.octopart.com/2SK170GR-Toshiba-datasheet-101287.pdf)
- 1N914 as subs for 1N914B  (http://www.solarbotics.net/library/datasheets/1N914.pdf)

Thx a lot!

 

[JohnRoberts]

Going to build my own Bloaks on breadboard using this schematic http://skipwave.net/images/bigfetbloak_v2.pdf and are about to source parts:

BC560 and 550 are easy to find at my favorite swedish dealer (electrokit...) but...

Is it possible to use:
- MJE340/350 as substitutes for MJE800/700  (http://www.fairchildsemi.com/ds/MJ/MJE350.pdf)

It would be a little easier if you included link to both parts.

I looked up the MJE800/700 and it is a darlington (twi devices in series for current gain)
the MJE 340 is a single device... So not close to the same thing.. You might make a darlington from 2x 350s in series.
[/quote]

- 2SK170GR as subs for 2SK170BL  (http://datasheet.octopart.com/2SK170GR-Toshiba-datasheet-101287.pdf)

The GR and BL are graded for IDSS or on current when 0Vgs.  The GR is 2.6-6.5mA is lower current but will probably work Ok since most JFET circuits use source resistors and/or don't run at 0Vgs.

- 1N914 as subs for 1N914B  (http://www.solarbotics.net/library/datasheets/1N914.pdf)

Thx a lot!

The in914 should be no problem.  I don't know what a 914b even means... most small signal diodes are pretty much interchangeable.

You can make your own darlington by adding small driver transistors in front of the 700/800, or just get the right parts.

JR

 

[tonedude]

Thank you!

 

[brujo]

Hello, the schematic links are dead ad I had no luck finding the schematics, could someone reupload them? thanks!