Babelfish ᄅſ....or FW J2 on Steroids .... or Not your Father's J2!

[gary s]

Hi ZM, can you advise if you have made any changes at all to schematics as shown for your various output stage options as shown in post numbers 1, 49, 64, 89, 99, 116 and 174 of this thread?

I plan to do the "Semisouth down and IRFP150 up version" as you call it.

Regards,

Gary..

 

[Zen Mod]

no changes, if schematic is followed by series of measurements

though , expect changes in Schade iteration , that one still needs ....... help

as Papa is used to say that Joseph Sammut used to say - this one need some help


🙂

 

[indra1]

... Schade iteration , that one still needs ......

What do you find to be lacking?

 

[Zen Mod]

need some more to investigate THD spectra and hopefully lower THD overall

 

[indra1]

I'm guessing the sound still too sparkly. This last few days I just found out that a schaded half F5 acts very similarly to a SIT in terms of harmonic spectra. 🙂

 

[Zen Mod]

well , I did it in LTS , while in vivo it's behaving little different , as always ....

so , solder time , it'll be

🙂

I like that one , you attached

 

[gary s]

Thanks again for your reply ZM, I will have a look back through the posts in case I missed something.

 

[Zen Mod]

well , nothing stops us of dealing in dedicated Tips 'n' tricks thread , once when I send them to Etheral Postal Realm

 

[coolnose]

ZM,

putting together my BOM for the poor man's iteration and wondering about CNY17... I find billion versions of this opto with different parameters... could you kindly specify which one to get ?

I suppose the 4n35 I have somewhere in a drawer are of no use in this case...

Thanks

 

[coolnose]

More looking, less talking...

Have info!

 

[Zen Mod]

-4

🙂

 

[coolnose]

Thanks,

I almost oredred the one from the component list... which is for package size only...

Max

 

[coolnose]

I suppose IRF1010 is overkill as replacement for IRF510 but looking at the datasheet I don't see any issues...

 

[Zen Mod]

can't tell

 

[coolnose]

Discarded, Ciss 20x higher... just put 510 in the basket..

I will never achieve "goal" to say I used what I had in my drawer.... well maybe Mofo soon 😀

 

[coolnose]

Concerning the LED string in the CCS what Vf of the LED should I aim for ?

Asking because I noticed that my green LED in stock are are at 2V... instead of the usual/assumed 1.8V.

Never afraid to ask stupid questions...

 

[Zen Mod]

plain peasant dull (not bright!) 3mm greens are always around 1V93 at few mA
nothing wrong with 1V8 or 2V , but out of that range is no-no

 

[coolnose]

Thank you!

So in fact looking for a 10V reference incl. the 1N4148 , or do I get this wrong ?

 

[Zen Mod]

you're right

simple as that

🙂

fine thing with LEDs as reference is - they're not too noisy , and you get some free light too



of course , when one needs more stable reference , there are other solutions , but for biasing cascodes this is most funny and more than good enough

 

[coolnose]

Thank You ZM,

concerning Zeners, same answer you gave to Dennis (I think) in other thread ? 500mW 2% ?

Do I take into account temp/current for value or just drop close value in ?

First time I try not to "paint by numbers" when building something, sorry it happend with one of your creation - well not really