[BUILD] 1176LN Rev D DIY

[Nadege]

I've already build a 1176 using your previous revission board and didn't
take time to carrefully read all the thread about your rev D before ordering
boards...
(It's a bit stupid)
I'm VERY confussed about input and output transfo wiring and sourcing. Would
the rev D work with the OEP I've used in the other 1176 as I'm really happy
with the sound of these ??
How to wire them ? I'm also very confussed about the input pot of the
compressor as it is totally different from the previous one....
Could you help me a little bit (wiring diagram???) pictures of finished
works,...
Thanks a lot

It seems that the cinemag output is the best thing to do, If anybody here is planning a groubuy i'll be VERY interessted

 

[kato]

BTW - the 3707's I ordered from mouser in jan 2007 all tested in the 150-170 hfe range. (too low.)

 

[Mailliw]

Why are the primary/secondary impedances on the orignal input transformer (and suggested replacements) so low if the 1176's input impedance is 20K?

 

[Sleeper]

Hope I can save Mnats a little time here.
There is really well drawn info about input and output impedences and wiring within the purple audio schematic. there are links littered all over this thread to that.

The OEPs will work.

there will be transformers on the blackmarket soon... the info is only a couple of posts back.

Kelly

 

[dmix]

[quote author="mnats"]dmix - what quantities are you quoting Cinemag prices for? My understanding was they had a minimum quantity of 5 at that price for the opt.

So you've tried the CMMI-2C on the input in this circuit? What can you tell us about how it compares sonically to the UTC ouncer?

I received my iron from Purple this week so I finished off one fabricated board to test the output circuit. It all works fine. I wouldn't suggest using anything but the Cinemag on the output. Though it 'works' with a normal output transformer or with the feedback winding removed the performance is badly compromised as you would expect.[/quote]

Hi Mnats, i ordered 2 of each and then mentioned to David Green from cinemag about some other DIYers that might be interested, he didn't mention anything about a minimum order, but i did buy 2 of each.

the CMMI-2C is 1:2 will use it in reverse

i can't tell you sonically as yet, will receive the shipment shortly

dmix

 

[ap123]

Can someone tell me the part numbers for those blue surface mount screw clamp connectors? Those aren't on the BOM that Kato made and they look quite handy. Also, in the rev d schematic I can't find the input pot. Is this before the input transformer which isn't on the schematic? I plan on using the O-12 reproduction from purple audio.

My last question is: I already stuffed the main PCB and completed the PSU section but now I've decided to build a dual mono unit. I'm using the Avel Lindberg Y236107 (30VA 30+30) power transformer. Is it bad practice to send the secondaries of the avel to two independently regulated PSUs rather than go through one PSU (as I would on the mnats psu pcb)?

And finally, am I crazy to try to fit these in to 1U? I don't see any problem with it except finding 1U tall VU meters.

 

[kazper]

Sifam Al-19 then code for inside outside, what ever cutout etc... format or you can use the Led VU's from the http://www.picocompressor.com/picocomp/grmeter.htm

There under terminals in the mouser book.
I'm not sure where your located but the main thing is the correct spacing between terminals. I can measure it and post later for everyone or mnats probably knows it off the top of his head.

 

[ap123]

kazper, thanks! I think it will be the Sifam Al-19WF. Total vertical clearance is 40.6mm it looks like. I need to make sure this will fit in a par-metal series 10 1U. I have one on order but the clearance is unclear in the PDF on the par-metal site. I will post my findings.

Terminal spacing on my rev d pcb is 5mm on center.

Thanks again...I really appreciate it.

 

[Sleeper]

TERMINAL BLOCKS

Here's the part numbers from my digikey order.
these fit the boards but they were just a little tight- the pins were square and I had to take a small file and round off the edges. took about 10 minutes for 2 boards, no big deal really

281-1436-ND CONN TERM BLOCK PCB 5.08MM 3POS
281-1438-ND CONN BLOCK TERM PCB 5.08MM 6POS

Kelly

 

[kazper]

you could also enlarge the whole but I'm unclear of how to properly do that without messing up.

I just helped another member and seen a Par-metal 10 series case for the first time. They are not exactly 1.75" cases more like 1.5" and there sheet shows this info. We used a nibbler to cut the top and bottom lip, that I got from Radio shack a few years ago and it worked very slick for what we needed to do. this was a GSSL project and the meter was a tight fit but it did fit. Some precision tools go a extra long way with this, but you don't have to break the bank.

 

[ap123]

I was worried about that with the par-metal specs. Those PDFs don't appear too specific. I was going to order my front panel but I need to make sure the system holes are ok. I sure wish frontpanelexpress had a gigantic user-based macro library. This forum should have an FPE macro library

On the terminal blocks, the leads on the 281-1436 aren't specified in the catalog. However, other black blocks have 1.2mm which look too large according to my trusty ruler. ED1624-ND (3 pos) and ED2223-ND (6 pos) are not only blue (like everyone's pics) but have lead diameters specified as .9mm. Could these be what everyone has?

 

[Sleeper]

If you found something with a .9mm I'd say that should do well.
.3mm seems about what I had to shave... it wasn't much.
Cheers
kelly

 

[kato]

Re: Terminal Blocks

Molex Brand fits. The spec sheet for Tyco/Buchannan brand is wrong. They claim 1mm width but parts arrived w/1.4mm wide pins. Mouser offered to have a tech measure the pins on the Molex before sending them out. They arrived and fit perfectly. (Their spec sheets says .89mm and it's still a snug fit.)

Mouser | 2 position | 538-39880-0302 | qty: 1/channel
Mouser | 3 position | 538-39880-0303 | qty: 7/channel

The above two fit mnats board with no filing required.
They are interlocking so you will lock two 3-position blocks together for the 6's. Also, they are black in color matching mnats board nicely.

 

[ap123]

Thanks kato...awesome.

Now I'm curious what pot to use on the input. I can't find this on the rev d schematic because I believe the input pot goes before the input transformer(?). I have:

R55: 25k linear (attack)
R56: 5M linear (release)
R23: 250k audio/log (output)
R??: ?? (input)

I'm planning on using the 0-12 reproduction through purple.

And finally, I swear I posted this question already but I can't find it. It is possible that I dreamed posting this question...if I did post this already please accept my apologies. I've been a bit consumed by this forum lately...ugh.

 

[dmix]

[quote author="ap123"]Thanks kato...awesome.

Now I'm curious what pot to use on the input. I can't find this on the rev d schematic because I believe the input pot goes before the input transformer(?). I have:

R55: 25k linear (attack)
R56: 5M linear (release)
R23: 250k audio/log (output)
R??: ?? (input)

I'm planning on using the 0-12 reproduction through purple.

And finally, I swear I posted this question already but I can't find it. It is possible that I dreamed posting this question...if I did post this already please accept my apologies. I've been a bit consumed by this forum lately...ugh.[/quote]


its a T600 attenuator on the input

check the thread

http://www.groupdiy.com/index.php?topic=10593

 

[kato]

[quote author="ap123"]
I'm planning on using the 0-12 reproduction through purple.
[/quote]

?? Purple stopped selling the 0-12 repro to DIYers on Dec. 31st 2006.
(Unless I missed something.) Search this thread for info on the attenuator / input pot. There's no readily-available, off-the-shelf solution for this one.

 

[ap123]

That thread was frighteningly inconclusive for someone with my level of experience! :wink:

Will this work?

http://www.duracap.com/controls_switches/audio_attenuators.pdf

 

[ap123]

Purple told me the lead time was 2 weeks on the input and output transformers.

 

[dmix]

[quote author="ap123"]That thread was frighteningly inconclusive for someone with my level of experience! :wink:

Will this work?

http://www.duracap.com/controls_switches/audio_attenuators.pdf[/quote]


yes the T Pad Attenuator cat number :T600 will work

 

[AnalogPackrat]

Hey ap123--could you post a price quote on those Mallory T600 units if you get one? I might be interested in a couple.

Thanks,
A P