F4 power amplifier

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jacco vermeulen

jacco vermeulen

Member
Joined 2004
jleaman said:
1500uf caps instead of the 220uf ones ?
Click to expand...

Jason,

you're here long enough to know that C3/C4 are there to improve the noise level.
Changing C4 to 1500uF and retaining the 3K32 for R5 adds another 8dbV to the PSRR, whether you have 27db noise reduction at 120Hz or 35dB is insignificant.

Remember that NP has a Francis Bacon storage room, stacked to the ceiling with IRF(Pass)244 and 220uF lytics.
At the mA level of the JFET stage i'd swap the electrolytic for a 10uF foil capacitor, not 1280uF more pugh.

ZenMod talks garbage 99% of the time, on the remaining spare moments the GENUS helps out others.
It's called intelligence with a sense of humor.(and skinny legs)
 
mpmarino

mpmarino

Member
Joined 2004
Remember that NP has a Francis Bacon storage room, stacked to the ceiling with IRF(Pass)244 and 220uF lytics.
Click to expand...

Yea, I'm starting to believe that almost anything can be built with 220uf caps, 9.1 zeners, Irf240, and a thermistor :)

The off topic junk talkers (like :devilr: (guess who?) , Jacco, and :) ( :) is Steen)) have the most to offer - these guys are freakin' good. Keep talking guys, and thanks :smash:
 
Variac

Variac

diyAudio Editor
Joined 2001
BurningAmp.org
Paid Member
Different threads have different tones. This one started off giddy and silly, like a party celebrating the F4 :Present:
Most threads are kept to a more sober atmosphere.

I think it is a creation that we all feel was really needed
:drink: :cheers: :drunk: :drink:

The reports of how great it sounds (even from the normally inscrutable Admiral Nelson) just sent people over the edge again I'm afraid....
:yell: :crazy:

:Pirate: Captain Variac
 
jacco vermeulen

jacco vermeulen

Member
Joined 2004
In that case,

this is the first 240/9240 Class A thing i did, early '90s.

0.33uF MKP, 6200pF KP, 820pF KP, 1100pF KS (aka Polystyrene)
In my case, a 4.7uF Siemens MKP, Roederstein KP1832, Siemens KS styroflex series.
Same power figures as the F4, No stinkin lytic.
 

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Zen Mod

Zen Mod

Official Court Jester
Joined 2003
zenmod.in.rs/
Paid Member
deadly serious ZM

forum can't be place for "question-answer" type of communication .

places for that have another names....... Quiz , for instance .

forum must be for communication between ppl, with sharing knowledge and helping just as parts of that communication.

next time when someone do not answer on my (lazy butt induced ) question,I'll use a gun .
 
Zen Mod

Zen Mod

Official Court Jester
Joined 2003
zenmod.in.rs/
Paid Member
jacco vermeulen said:
In that case,

this is the first 240/9240 Class A thing i did, early '90s.

0.33uF MKP, 6200pF KP, 820pF KP, 1100pF KS (aka Polystyrene)
In my case, a 4.7uF Siemens MKP, Roederstein KP1832, Siemens KS styroflex series.
Same power figures as the F4, No stinkin lytic.
Click to expand...


hehe
dreky hybrid

:devilr:

I'll loose Naah on ya ,dutchie .
 
luvdunhill

luvdunhill

Member
Joined 2006
very similar to my BOM, except I don't see what type of resistors you are planning on using... I was planning on using something like the IR HFA15TB60PBF instead of the MUR1560 devices. I also like those nice IEC inlets that have a switch, fuse, and some RFI/EMI filtering all in one little box, but I'm not sure how well those would work for a big power amplifier. Please post the price on the heatsink when you hear back from R-Theta!
 
J

jleaman

Banned
Joined 2002
plus.google.com/photos/104656656065604242634/albums/5725366675475046257?banner=pwa&gpsrc
Re: BOM - any comments

JimT said:
I near then end in refining this. Any comments before I order the parts?

An externally hosted image should be here but it was not working when we last tested it.


If you want the spreadsheet here it is:

Jim-BOM.xls

The toggle switch is the wrong one. I'll fix that and post again later.

Thanks
Jim
Click to expand...


FINALLY some useful information that is related to the thread, Thanks Jim
 
sklimek

sklimek

Member
Joined 2004
stanklimekstudio.com
luvdunhill said:
Please post the price on the heatsink when you hear back from R-Theta!
Click to expand...

Hi, I got a quote from r-theta about 18 months ago for the 65340-11.0"B heatsinks. Identical to the PD group buy. Their quote was $56.35 a piece for 4 heatsinks with a 50.00 set up charge.

If it could get to around 50.00 bucks per heatsink plus shipping and you are looking for a group buy I would be good for four of them. I talked to a Paul Korth at r-theta email - 'paul@odas.com' 310.781.2255 if that is helpful.

I also have a .pdf of the quote if useful.

Stan
 
Zen Mod

Zen Mod

Official Court Jester
Joined 2003
zenmod.in.rs/
Paid Member
Re: Re: BOM - any comments

jleaman said:



FINALLY some useful information that is related to the thread, Thanks Jim
Click to expand...


oh,boy.........I just love to be off topic
:devilr:

now you'll earn your own drek ;

http://www.diyaudio.com/forums/sear...63219434&sortby=lastpost&sortorder=descending

show me 10 ,even 5 of these, where you show that you actually push green button of your brain for anyone else - than just for your self.


I'm waiting .

but , I'm not holding my breath .



ZM ....... as Great Off Topic Contributor .......... in Dutch Colonies also known as Genius OT
 

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