All things Green Pre

[Phrazemaster]

And by the way, I'm still doing my build; I'm just extraordinarily slow at all this. I'm learning as I go. It's taking me many hours. I've made a lot of stupid mistakes. Like, I got some nice (expensive) switches for the phantom all wired up with a harness, to discover...I used too thick a gauge of wire and I couldn't get it through the front panel holes, which I slightly scuffed in trying to stuff them in.

So then I unsoldered the switches, but used too big a tip on my soldering iron and by the loose contacts I realized I had hosed the switches...

Ordered some replacements; haven't arrived yet.

Successes have included wiring up the 12-step switches; they work! I tested them with dmm and the readings look right. I couldn't figure out how it was working, until I really looked at the electron flow and then it made sense: since the common pole is connected to pole 12, in the first position the current has to flow through all 12 resistors first to get there...yeah, probably basic and easy for the hotshots, but Tesla I am not!

Although I am reading a biography about him; genius!

Well just thought I'd post an update. Things are going, just slowly.

 

[envelope]

just looking to identify the value of one unlabelled resistor on the layout. pic attached...PCB printing is too poor to be able to read, but it could possibly be 220R It is revision V.14 pcb

The resistor is directly beneath the LM339 above the left hand 1N4148 Diode.

 

[man-bot]

Should be 220R I believe

 

[Phrazemaster]

I installed this months ago. I don't remember how I arrived at my value, but I do know I'm extremely careful.

I have 220R as well.

Let us know how your build is coming!

Mike

 

[peterc]

http://www.mendelt.nl/greenpre_V14/_V14-All.gif

 

[pacemaker]

hey Peter !
it's been a long time !
Do you still have boards for the green pre ,
I built a 4 channel unit a few monthes ago,
i'm very happy with them in the studio,
but since i tried them in a live situation for voices,
i definetly want more for touring ,
regards,
Francois

 

[envelope]

http://www.mendelt.nl/greenpre_V14/_V14-All.gif

....thanks for your patience Peter...220R for the resistor

note to others thinking of starting this build.....although reading through the several hundred posts in the various green pre meta's takes more time and brain space to memorize, than the actual build itself, it is worth the effort, and the link that PeterC keeps posting does indeed include everything needed to build the unit....

 

[Phrazemaster]

Let me echo that, envelope.

This is a terrific project! If you're a newbie, you'll learn much about electronics, how to injure yourself with metalworking, and how to budget time/money.

Plus you'll have the satisfaction of creating something of your own.

If you just want a "paint by numbers" kit, look at seventhcircleaudio.com, or soundskulptor.com for some very highly regarded kits.

But if you want to get in, roll up your sleeves, and tackle something that first will be beyond you, go for it! Many here will support your journey.

I'm about 3/4 through with my set of 4 channel green pre, and hope to have them finished soon.

Take care,

Mike

 

[amaurythewarrior]

hi everybody, i'm new here
for one month or so i've been digging for infos, i think i know everything i need to, or almost, but i can't seem to find the infos about the power supply ... i assume other power 15v power supplies can do the trick but i'm not too sure ...

also, if someone still has PCBs for the v14 and the power supply, i'm interested, otherwise it'll cost me more than 50€ to get the pcb made ...

by the way, i'm also surprized that with the popularity of this pre, you can't find demos of it ! if i get mine complete, that's something i think i think i'll try to do

 

[man-bot]

I'm sure you can get boards and PSU board directly from PeterC or Ptownkid possibly (not sure - www.diypartssupply.com) if you don't want to make them up yourself.

 

[pacemaker]

Ptownkid don't the green pre kits anymore,
I myself would like a few boards,
maybe peter have a some boards for sale,
Peter ?

 

[man-bot]

I've built a few of the Green PSUs (boards from Ptownkid) but I can't seem to figure out what I have screwed up on this last one.  The postive rail and phantom voltages are bang on but the negative rail is running at about -10V.  The funny thing is that right off of the bridge rectifier I getting about 23v on the positive and only about -16.7v on the negative...  what the heck is happening here?

I have checked and double checked my component type and orientation - changed bridge rectifier and v regs, checked transformer voltage and all checks out fine...  I have  no idea why the volts on the negative rail are off right after the bridge rectifier.  Any thoughts on how to fix this?

Mike

 

[PAGEN]

hi everybody, i'm new here
for one month or so i've been digging for infos, i think i know everything i need to, or almost, but i can't seem to find the infos about the power supply ... i assume other power 15v power supplies can do the trick but i'm not too sure ...

also, if someone still has PCBs for the v14 and the power supply, i'm interested, otherwise it'll cost me more than 50€ to get the pcb made ...

by the way, i'm also surprized that with the popularity of this pre, you can't find demos of it ! if i get mine complete, that's something i think i think i'll try to do

Hi.

I'm would also like to get my hands on some boards. Maby it's time to get some made by some proffesional pcb maker and split out.
I have made one board by myself, but I will be doing some more. At least 3 more. Maby more when I heard the sound off them. I'm struggling with the silkscreen and soldermask, which is hard to make at home. I'm still a newbi and it's fun to build and get it to work.

Mats.

 

[dk329]

i got some extra boards from peter when i ordered. i have 8 green pre boards and 2 of his power supply boards if any one is interested. just pm me. same price i paid for them plus shipping

 

[dk329]

does any one have a current part number for the toggle switches? ???  ive spent the last few hours looking on mouser and digikey and am getting a headache

 

[amaurythewarrior]

hello everyone !
i'm desperately looking for the part list for the psu version 6a, and other docs that might be helpful.
once i have that i'll be able to  order the components ...

thanks !

 

[peterc]

Amaury

Go to www.twin-x.com search the diy section for album owner peterc . It is there

Peter

 

[amaurythewarrior]

hello peterc ! great, thanks ! now i can finally really begin the project !

thanks again !

 

[isophase]

which is better ? make the output of the green pre floating or is it better to ground all pin1 of the output XLRs ?

 

[isophase]

i finished my quad green
i've grounded all pin1 to the chassis through a thick copper ground buss, channel 4 had significant noise until i twisted the toroidal power transformer on its axe to find the position with lowest noise (did it by monitoring with headphones through a mixer) all channels work fine, i havn't set the CMR pot yet i will take it to my friend's studio in the next couple of weeks to calibrate it with their scope and do some testing. Metal work required a lot of patience i'm very exited now with my new preamps !
thank you to Peterc for the boards and off course to all the great forum members.