Re: Re: almost forgot:

dunno ...... Kochen macht Frei ........
ask man with frenchy hat
luvdunhill said:

dunno ...... Kochen macht Frei ........
ask man with frenchy hat

Re: almost forgot:
Simpler is better : this way it schmeckt the best : see pic
But appropriate wine is still must of course ....
Manu
Marc : I can send you HS from here. Just give me your adress (PM)... And sorry for delay....
Zen Mod said:Ingrédients ... si vous voulez vous régaler!!!
Simpler is better : this way it schmeckt the best : see pic

But appropriate wine is still must of course ....
Manu
Marc : I can send you HS from here. Just give me your adress (PM)... And sorry for delay....
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Man I wish I would finish my Pumpkin so I can quite reading this thread. I keep getting gas from it.
😉
😉
I decided to get them at a cafe in France near Annecy and the waitress refused to let me order them. .Kept saying that they were for "connoseurs" I finally decided to take her advice..
Variac said:... the waitress refused to let me order them. .Kept saying that they were for "connoseurs" I finally decided to take her advice..
Thats definitively a pity...
1. You're sure fearless enough ... 2. and a connoisseur you are.
If I have the opportunity to come to next BAF I will sure take some As. with me 😉
and cooked on Choky's amazing BQ stones
we could btw surely seduce Nelson to try this culinarity ...
Manu
zen mod...
this scary screeeeetching that's scared into Steenoe's brain... what conditions make this extra capacitor necessary?
this scary screeeeetching that's scared into Steenoe's brain... what conditions make this extra capacitor necessary?
luvdunhill said:zen mod...
this scary screeeeetching that's scared into Steenoe's brain... what conditions make this extra capacitor necessary?
huh .........
which capacitor ?
point me to that post ....... even if I have slight idea what you talking about
Zen Mod said:
huh .........
which capacitor ?
point me to that post ....... even if I have slight idea what you talking about
the 2u2 input capacitor that's recommended in the cookbook 🙂 something about DC being reflected....... that's when I went huh? 🙂
luvdunhill said:
the 2u2 input capacitor that's recommended in the cookbook 🙂 something about DC being reflected....... that's when I went huh? 🙂

aha- capacitorS ............
simple :
Pumpie is devily stable regarding offset between + and - output , but it is (like all simple Papalike gadgets) pretty temperature dependable , when talking about offset between both outputs vs. ground .
any value of offset voltage your Pumpie have on output (stricltly vs. ground) will be transfered to input , via feedback network , and value of that input offset will be exactly output offset divided with feedback network ratio ( meaning - if feedback net is set for 10x gain , input offset value will be 1/10 of output offset value ) .
that's not a problem in two cases :
1.if you are using some sort of rellay or switch attenuator ,
2.if you are able to set miniscule output offset , in range of several mV
that is a problem in two cases :
1. if you aren't patient enough to make proper case , with proper amount of ventilation ( meaning that you have ~ 45C on Pumpie heatsinks )
2. if you combine case with greater amount of output offset - with using plain pot .
that's already trivial truth that pots are screetchy and noisy ( during rotation ) if they are carrying both signal and DC in same time .
so - that was exactly Steen's problem - he has (had) plain pot , and not negligible amount of offset across that pot ;
solution is easy - put 2u2 in each input leg , between pot and Pumpie input ............... and enjoy .
btw - my Pumpie is dead stable , regarding both offsets ... but I was patient enough to repeat procedure : cover on , let it cook , cover off - tweedle with WRs , cover on ....... let it cook .......... cover off - tweedle ........ cover on
either that way , or double servo ;
to my ears - it's better without servo , and I tried several types of same ......
zen mod:
oh, this makes sense 🙂 I am going to use a stepped attenuator, maybe I'll be okay!
manu:
your package arrived! we need to settle up! How do you guy secure these heat sinks to the boards? On the large ones, it doesn't seem very possible to tap the edge, and the smaller ones seem to have a small channel for a pin, but there is nothing in the channel, and I'm not sure I have something that would fit... any ideas?
oh, this makes sense 🙂 I am going to use a stepped attenuator, maybe I'll be okay!
manu:
your package arrived! we need to settle up! How do you guy secure these heat sinks to the boards? On the large ones, it doesn't seem very possible to tap the edge, and the smaller ones seem to have a small channel for a pin, but there is nothing in the channel, and I'm not sure I have something that would fit... any ideas?
Hi, good news ...
🙂
Honestly I didn't secure the HS on the board, just soldered the fets and it appeared to be firm enough. Just isolated HS from board (just in case) with some layers of pieces of Teflon plumbing tapes.
Manu
🙂
Honestly I didn't secure the HS on the board, just soldered the fets and it appeared to be firm enough. Just isolated HS from board (just in case) with some layers of pieces of Teflon plumbing tapes.
Manu
luvdunhill said:it doesn't seem very possible to tap the edge
Sure it is, just requires the smallest tap size (and a column drill)
I wouldn't bother with the little ones, stick a dab of silicon glue under them.
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jacco vermeulen said:... silicon glue ...
Any example (easy findable in EU) ? .... Concerning glue I am always afraid there could be an issue because of the hot...
Manu
Manu said:
Any example (easy findable in EU) ? .... Concerning glue I am always afraid there could be an issue because of the hot...
Manu
"hot glue" ( plastic melted with gun) in small patches is also good enough - if you are not anal regarding looks of it

Z : I though you were on vacation?
I like "hot glue" altough little tricky in Handling ...
Something different :
for the those who have issue with a to high secondary voltage on toroids : there is a nice tuto - thanks a lot Philby -
with lot of nice (almost) self-explaining pics
about how to de-wind some turns in order to get proper sec. voltage - on french Pho
Very usefull
How to dewind some turns on your toroid to adapt secondary voltage to your needs
Manu
I like "hot glue" altough little tricky in Handling ...
Something different :
for the those who have issue with a to high secondary voltage on toroids : there is a nice tuto - thanks a lot Philby -
with lot of nice (almost) self-explaining pics
about how to de-wind some turns in order to get proper sec. voltage - on french Pho
Very usefull
How to dewind some turns on your toroid to adapt secondary voltage to your needs
Manu
Zen Mod said:
going in few hours 😉
better to say - "as soon my better half prepare all bits and pieces " ......
looking at that - we'll leave in a month or two .......

Manu said:Enjoy ! 😉
tnkya 😉
Zen Mod said:
"hot glue" ( plastic melted with gun) in small patches is also good enough - if you are not anal regarding looks of it
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Why is it I ALWAYS have to keep an eye on you?

Hot melt glue is great for fixating components, but for heatsinks it's a no-go, as it looses its properties at relatively low temp.
Silicone is the way to go. Just about any run of the mill silicone will do, the cheaper the better 😉
Magura 🙂
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