All things Green Pre

[amaurythewarrior]

hi everyone !
i'm still at the stage of deciphering the bom ... one thing i'm really not clear about is when i see axial0.2, radial0.4 etc ... even worse RB.2/.4
i know what axial and radial are, of course, but what's the number ? it seems it could be the diameter, but ... it doesn't match with the pcb so i must be wrong.
and as for the lead spacing, i guess it's not that important, is it ?
thanks

 

[isophase]

lead spacing

 

[amaurythewarrior]

ok so it's that simple ... i didn't think about it since for the condensers there's  a column lead space ...
thanks, anyway !

 

[amaurythewarrior]

mhhh . actually it doesn't make sense because for condensers there are both columns, and the values are different ...

 

[amaurythewarrior]

okay so i think i found out ... these are fraction of inches that's it ? ...

but i have yet another question
about the ... i'm not sure about the english word ... the power supply input module?well you know that thing on the back panel in which you plug the power cable. it's not in the bom, so i assume it must not be anything specific ?

 

[amaurythewarrior]

hmm there's not much action here ... just wanna say i started the building however i have to wait for my second order, because i had some parts which were too big, and i also forgot a few components ... which is obviously a beginner's mistake - now sourcing components seems easier, even though it's still the longest, and hardest part

it also let me the time to me to realize i had not respected polarity for a few components

and worst of all, that my transformer was not good at all ! i took a 110v, and here in france it's 230v ... even the secundary is 18v while i need 15v for the green

 

[peterc]

The numbers indicate tenths of an inch, so .2 is 2 tenths of an inch (5mm).

The mains inlet goes by various names, but IEC or kettle socket are very common.

18v will be OK, just make sure that there are adequate heatsinks on the regulators as they will have to dissipate more power.

Peter

 

[amaurythewarrior]

thanks peter c, i had realized it was in inch - after that everything was much clearer

well i had to buy a new transformer because of the primary anyway. what would have happened if i had connected the 110v  ?

anyway i can say i have learned quite a lot since i started this project - even though i'm still a total ignorant -i also have the intention to post samples if i'm successful - i know it doesn't mean much talking about DIY preamp, but i know it's something other people might be interested in

 

[peterc]

well i had to buy a new transformer because of the primary anyway. what would have happened if i had connected the 110v  ?

In my experience, it would have started vibrating & making odd little clicking sounds that got louder & louder & then started smoking, caps would have blown, & then I dont know cos I got to the switch......

 

[amaurythewarrior]

OUCH, so it is really a good thing i forgot some components ... well anyway i can't know if did anything wrong, until i test- but i'll check everything twice, and i guess it should be fine

btw some of the holes on the psu pcb are too small, not easy to sort out when you don't have the tools ...

 

[isophase]

yes, try to get a 0.8mm drill bit this will sort it out 
i just calibrated my quad green with a scope, i took it to the studio for some testing in real condition... will report back soon
thanks again peter for the great project !
all the best

 

[amaurythewarrior]

that's precisely what i did (0.8mm exactly actually) and it was sorted in no time !i should get my components in 1 hour or 2, can't wait
btw iso, you have no output control on your green (does that have to do with all the components you left out ?)

 

[isophase]

no this is the metering section, the output trim is the (optional) 10KLog pot

 

[amaurythewarrior]

i had no idea the metering section took so much space !

 

[amaurythewarrior]

tried to plug it for the first time, after a few seconds (like really, no more than 5 seconds) PAF! (don't know what would be the sound english), a high pitched sound. so i unplugged immediately - any idea ?

 

[isophase]

have you measured your power transformer before feeding the PSU board ? check your wiring ? shorts ? filter cap polarity ?
be careful while working with the mains voltage! don't kill yourself !

 

[amaurythewarrior]

no actually, i guess it's a little late that now but i'll try tomorrow anyway ...

after the problem before i tried after making sure there wasn't  a short circuit or something ... and i've had black smoke  over the psu caps ...
i'll probably try to read more on safety tomorrow anyway ...

thanks

and goodnight because here it's way past the hour to get to bed

i'll check everything again tomorrow - hope i haven't fryed any component ...

well anyway even if that's the case, i guess i only learn through expensive and frustrating mistakes ...

 

[peterc]

Please can we keep this problem to one thread?

Thanks

 

[amaurythewarrior]

hi everybody
just a quick word to say my green is  finally work - well the led meter doesn't work, for some reason, but the preamp works just fine !
so thanks to peter for his design, thank to those who helped here, thanks to all those who shared useful informations on the forum !
i'll make a more complete post about my experience later, when my pre will be in its enclosure etc. i believe i have quite a lot of things to say that could be useful for beginners. oh, and samples, too !

i was lucky to get help from a guy on the french version of audiofanzine, who was a retired electronics engineer, and he was really nice, proposed me to call him so he could help me better !

so that's pretty much it, i'm already looking forward to my next project ! (and i'm supposed to make 1or3 more green channels, but i don't think i'll make all3 so if soeone wants  pcbs )

 

[Teije]

Hi, i´m Martin from Argentina. I´m triying to build a green pre but I've seen that older versions (before v14) don´t have HPF, lleds or the phase switch. As really don't need any of this I started looking for the layout of this version but I can`t find it anywhere. Does anyone still have it ? or is there anyway to mod the v14 to bypass these section? Thanks