diyAudio (
-   Pass Labs (
-   -   My F4 Build (

Einric 30th December 2012 12:37 AM

My F4 Build
1 Attachment(s)
Well.....My F4 is under way.
Santa brought me matched triplets of 240/9240's all the way from Israel.
He also brought me some 74V/170V's from Hong Kong I hope they are genuine.

My question is on the trimmer pots; how do you know they are oriented properly for clockwise gain in Ω?

Also I ordered TO-92 heatsinks just for kicks; should I thermally couple the 74 & 170?

The Space Egg Corp 30th December 2012 06:31 PM

I was just thinking...
...I wonder if Einric is gonna start a build-thread for his new F4 ?

Oh well...need not wonder, any longer !

Hi Einric !

I hope you didn't get your 2SJ74's from where I did !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!



If you didn't; tell me where you did...
...I could do with some genuine-product !

The Space Egg Corp 30th December 2012 06:34 PM

Sorry Einric...
...dunno much about the F4.

You got 'V' Tosheys ?

What do they measure ?
( 9v battery... Jazz )

Marra 30th December 2012 07:32 PM

Stick with Spencer for your jfets.

Einric 30th December 2012 07:51 PM

I don't know how to measure them, neither of my multimeters have transistor test on them.
Yes they were stated as Toshiba V's.
I purchased them on E-Bay from HKaudioparts, the 74's were listed at ldss=17.07ma.
My 170's came from E-Bay from UTsource.

Einric 31st December 2012 12:19 PM

Could anyone suggest a good transistor matching schematic that I could build on a perfboard?

vdi_nenna 31st December 2012 01:33 PM

1 Attachment(s)
This doc might help.

Einric 31st December 2012 05:58 PM

You Rock!

Einric 31st December 2012 09:58 PM

I just so happen to have an LM317 on perfboard ready to go.
Would I be able to use this same setup at the working voltage for the application?
I would assume yes since there are no resistors in the circuit.

vdi_nenna 31st December 2012 10:25 PM

How about a 9 volt battery?

All times are GMT. The time now is 09:03 AM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright ©1999-2017 diyAudio