[BUILD] 1176LN Rev D DIY

[kato]

Sprague is pretty big to fit in that spot.

You might order some of these as a backup.

 

[Josiah]

Thanks for the quick reply Kato... ;D

I noticed that the Sprauge spacing is 18.26mm or .71" and it seems to match the extended thru hole locations on the Rev D board at location C1. I'm alright with it being a tight fit "if it will work value/voltage wise". Do you think the 100V Sprauge option will work or should I just use the 50V WIMA you suggested? I might buy both and see what works or fits unless you see a problem with increasing the voltage to 100V. If the Sprauge is oversized its a obvious no go...

Is that a DEFENDER avatar...

JZ

 

[kato]

Is that a DEFENDER avatar...

My first cartridge, saved for with paper route money.  :'(

Using a higher voltage cap is no problem.
I'd still order both. It's good to have extra 1uF caps around. They get used a lot!

 

[Josiah]

Thanks for the info Kato, you are a life saver!!! Defender was and is one of my favorite games of all time. I can remember being glued to the ATARI for hours playing that game when I was younger...good times

Well I will order both and give the giant Sprauge a try. I will report back later if it worked and or fit.

JZ

 

[Tweekhead]

Stuffed Rev D, just think I reversed the molex 3 pin header for the shorting pin R44 "upside down that is ;D".
Off to attempt wiring it up in the box!

 

[Josiah]

I have a REV D unit that blew a 300ma fuse on start up today. Only once in seven days, it has worked fine every other day since the build completion. I have the METER "OFF" push-button being used as a main AC power on/off. I am switching the neutral, Toroidal Brown/Grey. Is this potentially causing my problem with something not transferring properly across the Common and Normal Closed poles when I depress? I switched to a 400ma fuse since I read a few people were having the same problems. Is there a capacitor I can place on the switch to tame the voltage current rush?

 

[Echo North]

I'm no expert on in-rush current, but I do remember reading a while back that in-rush can vary widely depending on the mains phase and toroid state at the time the switch is "flipped".  I've blown 250mA slow-blows from time to time.

If you have the new switch with the black power switch you should be switching the "live" (or both).

A 400mA slow-blow shouldn't blow.

Mike

 

[Brolik]

Hi guys. Question. I built the Rev D with no problems (awesome build, plenty of info here in the thread) a few months ago. We were using it in a session a few days ago and someone pulled and reinserted the patches while it had signal. It immediately started to make crazy oscillations and not passing audio. The oscillations come up in particular when the output pot is turned up, they aren't simple sine waves but crazy like a was screwing with the oscillator on an analog synth. Also the meter is going haywire. For instance, when on GR and the input and output are turned all the way up it shows +3.

Any idea what may have blown? Something obviously shorted when it was "hot swapped", but I don't necessarily know where to start looking. I was unable to find anyone in the thread with exactly the same situation.

 

[telefunk]

First of all I´d like to thank Mnats, Mike and especially Jakob E. for makin´all this possible. THANKS!

ok, I´ve built the rev D with EA-5002 output and it works like charm, love it. But since i´ve also built mnats rev J 1176´s with output OEP´s in 2:1 wiring, there is one little important difference:  when i patch the Rev J´s to my Harrison desk (insert point signal -6db) the rev J has the output knob nicely in way over half way position and I still get around 1.23 volt signal output BUT with rev D I only can slightly open the output knob and its already really hot!

So, too much gain! What can be done?!?! Is there a different output transformer wiring or something?

 

[dmp]

It immediately started to make crazy oscillations and not passing audio.

Sounds like a shielding or ground problem - with transformer balanced ins & outs, I don't think hot-swapping would cause any problem. I do it all the time 

 

[scottyjneilson]

So I am pretty New to the DIY world. I have the PCB stuffed have checked all my joints and wiring several times upon firing up the unit I made the mistake many before me have made by improperly wiring the output tranny and Frying R32. Once I replaced R32 and plugged into the wall and into my interface. NO AUDIO?????????? it will not pass audio at all. I have checked as much as I can possibly check with my limited knowledge I have even cracked open my dads notes from basic electronics taught in the navy for servicing missiles which covers very basic circuits all the way up to more advanced and have not come across much. I have looked extensively through this forum for months before even thinking about posting and have not come across anyone with the same problem as me. I have been looking for what my Q values should be but have not found any reference.  Any direction if any would be of a huge help. ???

 

[shabtek]

scottyj:
there may be some generic troubleshooting threads around here...
check the power supply.
make up a signal tracer (probe with 10k resistor and a bipolar cap in series to an amp/speaker), feed a signal and probe from input working towards output, find out where you lose signal. that will narrow it down.

 

[Philo]

I just built a rev D using the transformers and parts that Hairball Audio sells, and the Mouser parts list.

What would be really useful would be a complete wiring guide for the MNATS D Rev 2 board with the Hairball enclosure and switches.

The attached version is ALMOST complete and correct, except that:

1) the OT wiring has the pinout order for the MNATS Rev 1 circuit board (instead of Rev 2, which uses a different order);

2) the OT wiring shows a RED wire connected to pin 2 of the output jack and a BLUE wire to pin 3 (when it actually needs to be reversed to work with the EA 5002 output transformer); and

3) it would be helpful to clarify that you can/should use a shielded cable for the connection from the DPST switch to the ratio board, with the shield carrying the BLACK signal and the interior wire carrying the GREEN signal.  Maybe it could also clarify that the 22 wire to the DPST is the signal BEING switched by the DPST, and that when it is connected to BLACK the 22 signal is grounded and the compression is turned OFF.  The 22 wire goes to the middle/single pole of the DPST pot that Mouser and Hairball sell.

The listed OT pinout in the attached diagram will fry R32, and the reversed wiring to the output XLR means you will get low or no output.

Ask me how I know these things.... Sad Sad Sad

The reversed wiring from the OT to the output XLR is particularly subtle, because it is the opposite of every wiring guide I've seen (though clearly evident if one looks at the wiring diagram for the EA5002 OT posted on the Hairball site a few months ago).

This isn't THAT hard a project, but a complete/correct wiring guide for the Hairball parts would have saved me a significant amount of time/trouble.

I don't have the graphics chops to fix the attached.  Maybe someone else can do it.

I think I've finally got the unit working now, though.   Smiley

Philo

 

[Echo North]

http://www.groupdiy.com/index.php?topic=28923.msg514969#msg514969

 

[adrenalin]

Hi folks!

I'm from germany and new here in this forum and start to build a Hairball 1176 Rev. D.

I read about a "SG-1176-RevD-Wiring_ALLv3.pdf" but no link works. Can somebody post the manual?

Best regards

 

[Echo North]

Shoot me an email.

I have a few docs that will help.

I'll have an updated wiring doc posted in 2-3 weeks.


Mike

info at hairballaudio dot com

 

[adrenalin]

Hi,

try to buy some Transisitors (which are not in stock by mouser).
So is there a difference between the "2n3391" and the "2n3391A" transistor?

Kind regards

 

[Ben J]

I finished wiring up and calibrating my RevD, but it sounds like it's boosting everything above 500Hz and attenuating everything below. Sounds very thin and harsh as a result. When I run a 1kHz @ .775v, it sounds like a square wave, but only in +4 and +8 modes.

On top of the distorting problem, it seems like there's an increase in output in GR mode (or an attenuation in +4 & +8).

I've checked and re-checked according to the updated wiring guide someone made (I'm really bad at reading schematics), and can't find what is wrong.

If anyone could help me out, it would be greatly appreciated! It would be nice if my first DIY attempt was worth it.

http://dl.dropbox.com/u/324863/1176_03.jpg
http://dl.dropbox.com/u/324863/1176_05.jpg
http://dl.dropbox.com/u/324863/1176_06.jpg

 

[Echo North]

Only glanced for a second but you have C19 and C23 reversed.  19 should be the tantalum and 23 should be the electrolytic.

Switch those and test your +30 and -10 power supply test points.

I'd carefully go over the whole board and check it against the BOM before moving on.

Mike

 

[Ben J]

Good catch.

I'm good on the power supply (29.3 & -9.7).

The problem is still there, so something else is up. I'll look the board over.

Thanks