as some of you already know for preceding story : http://www.diyaudio.com/forums/pass...high-end-off-topic-thread-67.html#post2264960 ...... I'm blessed with Papa's Suprise ...... ( where is that "notworthy" smiley when you need it ..... 
) .
there is rest of story .
I'm certainly one of not many , having opportunity to dismantle FW chassis in pieces ; as Papa likes AR2 , he didn't put usual Donut and caps in it , probably counting on fact that Vladimir will bring it all the way on his shoulder ( not having enough trust in Air baggage departments ) ......
anyway - little jewel box is even without these few parts heavy enough ...
so - to have Papa's Surprise Amp in working condition I had to do few things :
.... install new Donut ; what I already had on my shelf is just right (to squeeze in ) size - 4x18Vac/800VA ; according to that - decision to use 2 Graetzs per channel is logical , same as dedicated filter bank per channel .
so - 2x18Vac windings , two bricks , 4x 33mF/25 Panas , along with 2x 0R1 in CRC ; all that per channel
I didn't want to make new holes in bottom plate , so nice Cu plate is cut and bent , to serve as donut and bricks holder . I also made new filter pcb ( wisely sprayed in black ) , while Papa's original one , along with two finest original FW Chinese Porcelain 35A bricks will end in some less demanding project ( maybe some HP amp ) .
power wiring is made from finest quality cut-in-dust LS cable , produced by local factory
Donut squeezed in sandwich (top & bottom ) of soft rubber ; my usual praxis for all toroids ; you can rotate it few degrees and move about 5mm side wise , but it's secured completely
so - few pics for start ( I'm lazy bstrd , so random order is my native state)
) .there is rest of story .
I'm certainly one of not many , having opportunity to dismantle FW chassis in pieces ; as Papa likes AR2 , he didn't put usual Donut and caps in it , probably counting on fact that Vladimir will bring it all the way on his shoulder ( not having enough trust in Air baggage departments ) ......
anyway - little jewel box is even without these few parts heavy enough ...
so - to have Papa's Surprise Amp in working condition I had to do few things :
.... install new Donut ; what I already had on my shelf is just right (to squeeze in ) size - 4x18Vac/800VA ; according to that - decision to use 2 Graetzs per channel is logical , same as dedicated filter bank per channel .
so - 2x18Vac windings , two bricks , 4x 33mF/25 Panas , along with 2x 0R1 in CRC ; all that per channel
I didn't want to make new holes in bottom plate , so nice Cu plate is cut and bent , to serve as donut and bricks holder . I also made new filter pcb ( wisely sprayed in black ) , while Papa's original one , along with two finest original FW Chinese Porcelain 35A bricks will end in some less demanding project ( maybe some HP amp ) .
power wiring is made from finest quality cut-in-dust LS cable , produced by local factory
Donut squeezed in sandwich (top & bottom ) of soft rubber ; my usual praxis for all toroids ; you can rotate it few degrees and move about 5mm side wise , but it's secured completely
so - few pics for start ( I'm lazy bstrd , so random order is my native state)
Attachments
so......
Papa sez
that pcbs are from early pre-production ; meaning that pcb itself is right as schematic posted in first post in famous F4 thread ; later and final iteration have few changes - mainly with goal to save and secure tiny fragile input Jfets from excessive input signal which , in case of amplitude greater than actual F4 working voltage , will burn them in silent puff
I had dilemma few days - leave it as is , counting on fact that I don't need much of input amplitude for my spks ...... or to tweak pcb a little and make it according to final schematic ; naah ....... as Papa sez in one e-mail - " I though that you will put something else in that case " , decision was made - I'll leave present as is , but I must play with it a little ; so - every butcher detail you'll see on pics is made as change to that schm .
electrolytics are my fave - Elna 470uF/35V/125C , maybe because I have few kilos of them ;
bypasses on two Elnas in power filtering are 100n/some-film-who-really-care-which-type ; bypasses on two signal carrying Elnas are 10n MKC - polycarbonats
one funny thing is - major-trouble issue for Vladimir , and also major-laughing issue for me - fact that front plate was badly scratched in transport (probably bubble-wrap slipped and back side of zip in Samsonite made those scratches ) ,exactly where Papa's Surprise sticker is put , on pics in linked post above ;
I had instantly cunning plan ( I'm pretty often in Baldrick mode) to send front plate in capable hands of local Metal Guru - Leonardo ( nick on Baby Diya) ;
said and later managed - Leo cleaned existing elox , brushed , made new elox and Fugly! new logo .
possible similarity with existing FW logo is pure coincidence , of course , and your's Mighty ZM is responsible for that coincidence
I know that my fave Dutchie Jaccovitty is dumb as Dutchie Whale , so here is link to wikipedia - meaning of Koan ..... for his eyes and education only
: K?an - Wikipedia, the free encyclopedia
why "Koan" ?
just because Papa's crumbs , thrown in ZM's direction , are usually 3 times stiffer than his usual PassDiyA crumbs ......
Papa sez
that pcbs are from early pre-production ; meaning that pcb itself is right as schematic posted in first post in famous F4 thread ; later and final iteration have few changes - mainly with goal to save and secure tiny fragile input Jfets from excessive input signal which , in case of amplitude greater than actual F4 working voltage , will burn them in silent puff I had dilemma few days - leave it as is , counting on fact that I don't need much of input amplitude for my spks ...... or to tweak pcb a little and make it according to final schematic ; naah ....... as Papa sez in one e-mail - " I though that you will put something else in that case " , decision was made - I'll leave present as is , but I must play with it a little ; so - every butcher detail you'll see on pics is made as change to that schm .
electrolytics are my fave - Elna 470uF/35V/125C
, maybe because I have few kilos of them ;bypasses on two Elnas in power filtering are 100n/some-film-who-really-care-which-type ; bypasses on two signal carrying Elnas are 10n MKC - polycarbonats
one funny thing is - major-trouble issue for Vladimir , and also major-laughing issue for me - fact that front plate was badly scratched in transport (probably bubble-wrap slipped and back side of zip in Samsonite made those scratches ) ,exactly where Papa's Surprise sticker is put , on pics in linked post above ;
I had instantly cunning plan ( I'm pretty often in Baldrick mode) to send front plate in capable hands of local Metal Guru - Leonardo ( nick on Baby Diya) ;
said and later managed - Leo cleaned existing elox , brushed , made new elox and Fugly! new logo .
possible similarity with existing FW logo is pure coincidence , of course , and your's Mighty ZM is responsible for that coincidence
I know that my fave Dutchie Jaccovitty is dumb as Dutchie Whale , so here is link to wikipedia - meaning of Koan ..... for his eyes and education only
: K?an - Wikipedia, the free encyclopediawhy "Koan" ?
just because Papa's crumbs , thrown in ZM's direction , are usually 3 times stiffer than his usual PassDiyA crumbs ......
)
tip :
if you want to save surface around screw holes from damage , use plastic washers ;
if you don't have plastic washers handy - DIY them - from roentgen foils
all you need are ( what's proper word) - hole making tool and scissors .
funny - I have full box of these foils in A3 format, scavenged from local health center ...... they're good for many things in electronic
if you want to save surface around screw holes from damage , use plastic washers ;
if you don't have plastic washers handy - DIY them - from roentgen foils
all you need are ( what's proper word) - hole making tool and scissors .
funny - I have full box of these foils in A3 format, scavenged from local health center ...... they're good for many things in electronic
but remember that that phrase is reserved for my Dutchie Whale , as expression of love ; but don't tell him that - he's spoiled too much already
exactly as proper F4
usual FW job - honest amp , no bigger than life ; I can't ask for more
try at junkyards ; that piece is surplus (sort of ) from little local factory
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