8 Channel, 3U NEVE 1073 completed

[MikeFFG]

cool thanks I'll check that out!

 

[ilfungo]

What can I use as Trim Faders?
Mouser code?
Thanks

 

[MicDaddy]

Jumping in on the 1290 wagon!    ;D

Any chance someone has done a 'digikey (or mouser/etc..) quick-checkout' with the current BOM??  (I know I'm lazy)

 

[seavote]

sorry if its been explained befor and i confess now i've only read up to page 13 of the thread.
i have 2 boards i bought from a board member. they are marked  version 2.2.  i see that i should use the older assembly instructions (for anything older than 2.4)
but im wondering  what the difference is between 2.0 version i see referenced in the thread and the 2.2 version that i have. thanks
8) 8) 8) 8) 8) 8) 8) 8) 8) 8) 8) 8) 8) 8)

 

[dutu]

Hi!

I am still working on the power supply.. that's why i didn't post its layout, schematic and bom yet.

I worked it after the jlm audio power supply schematic (the one Martin reccomends). I made the layout (no mistake in the connections, checked 100 times).

I purchased a transformer that is rated 2 x 24V, at 2 X 0,68A. If I plug it in the outlet alone and measure it (without being connected to the power supply), I get 25,8V (side to center) and 54,3V (side to side - or end to end of the coil).

Then, after rectifying, i get about 40V and 110V..

I connected the center tap and a side to the 24V circuit, and it works fine.
I connected the sides to the 48V circuit and the LM317, protection diode across input-output pins and the 5k trim pot burned out (sparks and flames). The trim pot melted!!

I did this again and got the same results. Then, I replaced (the 3rd time) theese components and conected the center tap and a side of the transformer (instead of the sides-ends of the coil) and worked perfectly (was able to make another 24V circuit).

If I'll connect the 2 ends of the coil again, I'm sure it will burn out again.

But here's what I don't understand. I worked exactly by the schematic and that's how they do it. This means that the problem should be in my transformer?.. Is it too hot? If I take out turns from the secondary, would it then be able to power 2 preamps?

I'm waiting for sugestions.

The original JLM Audio schematic is here:

http://www.jlmaudio.com/JLM%20PowerStation%20Ver%202%20Schematic.pdf

Ovi

 

[MicDaddy]

Received 8x EZ1290 pcbs yesterday!! 

Thanks Martin for the speedy turn around!!!!

 

[sr1200]

So this is my plan for the layout of my build... any suggestions or warnings before i commit?

EDIT:  I was thinking of stacking the input/output jacks on top of one another not side by side...

 

[briomusic]

should be ok. alternatively you could have the input iron inbetween the pcbs, to get more distance from the output transformers.

 

[sr1200]

There wont be a problem with proximity having the input TX close to the boards?

 

[briomusic]

There wont be a problem with proximity having the input TX close to the boards?

No, that's not really a problem. I would say as far away from the power trafo followed by as far away from each other.

 

[dutu]

Hi! Please help!! )

It's about the 48V rail of the power supply... how come theese power supplies work if the LM317 can handle MAX 40V (out-in)? My LM317 from the 48V rail is always burning... tried a lot of times. I did exactly the JLM Audio's power supply. My transformer measures 26V - 0 - 26V AC and it's rated 24-0-24. The 24V rail is working perfectly.

I plugged the 48V rail into a 24V coil of the input transformer, and I have another perfectly working 24V rail. But if I input 48V (actually 56VAC), the LM317 burns out.

Thanks!

Ovi

 

[Ptownkid]

40V is the max input output DIFFERENTIAL. They can handle hundreds of volts as long as the difference between the in and out is 37V or less.

 

[dutu]

Thanks!

Yea...You're right. But still, I think here lies the problem.. on the input I've got about 110VDC... Have no idea why. After rectifying, I have like 80VDC.. (the transformer outputs 52VAC)

All measurements are without a load, i.e. without a preamp plugged into..

What transformers do you guys have?

Ovi

 

[madriaanse]

Hi Guys, just wanted to let you all know I will be volunteering in Haiti from 1/15/11 to 2/15/11. While I'm there I will have very limited or perhaps no access to email, and I will not be able to mail PCB's during that time period. All current orders have been shipped.

All the best,

M.

 

[sr1200]

Wow man, that is awesome.  Best of luck, stay safe and healthy!

 

[gevermil]

would this switch work for this project or the new 1073


71BF30-03-1-11N  , it dose not have the adjustable stop but ?
I have a chance to score a bunch cheap

http://www.alliedelec.com/search/searchresults.aspx?N=0&Ntt=71BF30-03-1-11N&Ntk=Primary&i=0&sw=n

Thanks

 

[sr1200]

So i got all the parts together and hooked up a channel last night.  All voltages look correct on everything. (no smoke or fires...phew)

I am using the JLM powersupply, maybe someone can give me some advice on this.  there is a -24V rail that is not being used on the PS.  If i change the regulator to be + (just put in another 317) and roll the pot down to 12v would there be an issue with doing this?  (does there HAVE to be a negative rail on the PS...) my theory is for **poop** and im not sure changing this would mess something up.

(in the end id like a +48v, +24v, and a +12v rail off this thing)

 

[kambo]

check with schematic, you need to reverse the polarity of elec caps etc....

 

[dutu]

Hi guys!

As I promised, this is the finished power supply PCB and BOM. I exactly cloned the JLM Audio power supply, and did no changes anymore. ;D

I could only make a JPEG file, but, in order to have the exact scale, you should know it's 600dpi resolution. I already mirrored the pcb, you just have to print it.

I've made it, tested it, and works perfectly. Be very carefull not to make solder bridges between pads. I burned a couple of sets of diodes because of this. Check with a magnifier!!  ;D

http://www.legacy.ro/neve_power_supply_final_600dpi.jpg

Make sure not to forget the 3 jumpers (thick lines on the top mask), and there is a wire going from D10 (there is a hole) going to the 48v output terminal (there is another hole)

Martin, it would be great if you could make some boards for the people here. I'm sure they'd wanna buy some. I worked mine manually and took me half a day )

Ovi

 

[sr1200]

So, im still waiting on a couple of insignificant parts (trim pot and face plate)for my project... i decided to hook up the parts I have (with great success!!!)
I do have some questions as far as hooking all the added bells and whistles ive added to the project though.

I have a VU meter and the JLM go between (48V phase and pad).  I was unable to get the VU to function properly BEFORE the output tranny.  (if i send a lead off the output tx the meter works really well and is pretty damn accurate... still needs calibration).  What i would like more (and would be more useful, since i can see the output levels going into the DAW.... ok well, i guess its just an asthetic thing either way lol but I'd like it to work proper) is to have the VU respond to the INPUT signal rather than the output.  And im not sure if i should put a lead stemming off the INPUT TX or from somewhere on the actual EZboard.

And do i have this set up correctly? 

I have pin 2 and 3 going into the go between (input) the 48v and the 0v also goes in from the powersupply. I then have the + - out of the go between going to the INPUT TX (is that right?) and pin 1, goes from the XLR input right to the input TX (should I have the shield(pin1) go to the 0v of the go between?)