**** Neve BA183 component layout ****

I posted this in another thread, but it occurred to me it might be good to post it individually as people might not read the other thread, so here it is.

The BA183 has no silkscreening to help in populating it, and it seems the vast majority of 183's floating around have only the output section populated, so I hope this will help people out. There's a lot of Neve iron out there that needs a circuit to go with it :wink:, so don't be afraid to snag some BA183's for your Neve project. They're almost always on ebay - usually in pairs- for pretty reasonable.





The first picture is of a typical BA183AM (output-only loaded) with the missing preamp components drawn in (pins N-V). I took the pic in the shutter of my front window so you can see the traces on the other side and then drew in the additional component layout using Powerpoint.

The second picture is of a completely populated and refurbished card. When I refurbish one of these I always install new transistors, new electros and a new 47-ohm/1-watt resistor in the output section. The 47-ohm resistor is mounted immediately below the 2N3055 heatsink, and it just cooks. I always replace the original with a fresh one as a matter of caution.

Hope this is helpful!

Peace to all,

JC

Thanks! Very cool.

Very cool indeed :thumb:

Thanks Joel for the info.

Oh yeah. Another thought:

Don't be concerned about the minor pinout differences between the BA183 and the BA283. The differences concern pins that aren't accessed in preamps (or any other Neve circuits that I know of). The same pins used to make a 1272 (or 1290/1073) are shared by both, so in practice they are interchangeable.

I had a 283 go bad in one of my 1084's last year and a crammed a 183 in there to get me by until I could fix the 283. Other than the snug fit (183 is a little deeper than a 283) it worked perfectly.

Enjoy!

JC

thanks much, I just picked up 2 1/2 stuffed ones, so no I can finish easy!

Thanks!

Hi Rascal,

That's cool! As a note, some of your parts are shuffled around on the bottom left of the NV side. Electrically it's correct, but on original boards I've seen:

the 51K connects on the left side of the "T" (pin p) and connects to the hole below the 10k

the 22uF/16 connects to the right side of the "T" (pin p), upper connection is correct.

the 1000pF connects to where you have the top of the 51k connected, upper connection is correct.

Not to be nitpicky of course..... :grin:

All the best,

Martin

Off topic - Newmarket on the 2N3055 blimey!
For those overseas - imagine a straight line about 30 miles long

St.Ives....Cambridge.....Newmarket
Then ten or so miles south of Cambridge - Royston (ie Melbourn)

Thanks for the info, Martin! I actually had to figure out that dang arrangement myself.

I bought a pair of aux modules a few years back that each had two 183AM's (output stages only), and I wanted to use them as full 'AV' versions, but couldn't find info on the layout anywhere. So I just sat down one evening with a 283 schem and a dry-erase marker, studied the traces and the drawing and just started connecting drawing lines between pins on the thing until everything was filled and it all connected like it should.

Cool thing is that the first one I fired up worked perfectly with no problems whatsoever!

I wish that happened all the time. :?

Thanks again,

JC

Something like this?


Here's the page for the missing layout http://www.vintagedesign.se/docs/B183.pdf

If I'm understanding what I've read about these boards so far, it seems the onboard pot (4K7) is there to adjust for symmetrical clipping under full output. Did you check this after installing new caps, etc.? If so, how did you go about setting it?

Cheers,
--
Don

Hi there,

All links for this thread are dead.

Could somebody who owns one be kind enough to post some photos or link to  B183 component layout ??

That would be lovely ;-)

Yep ! this would be lovely !
thanks !

Check ebay.  There may have been some on there recently with good pics.  You can also look for old Neve schematics, maybe they are in the documents here... which usually include a line drawing showing the component placements and positions on the cards.