Have you ever admitted defeat with a DIY project?

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Che_Guitarra

Well-known member
Joined
Dec 22, 2012
Messages
227
Location
Australia
I'm almost at that point. 

I have a problem with my 1176 that lies somewhere between the XLR input and connection to the PCB. I've tried every single troubleshoot, read every available web page and replaced everything in the signal chain in fear of a component fault.  Nothing.  Grounding and continuity is correct at every point, solders are all rock solid.  Yet if I patch my rev A 1176's input chain across to this rev D it works perfectly.  Grrrr!  Frustrating!


Just wondering if you guys have ever waved the white flag with a project and visited an electronics repairer to solve your problem?
 
read this:

"The description of this aerial battle from Saburō Sakai is different. He spotted eight planes in two flights of four and initially identified them as F4F Wildcat fighters. When he attacked - followed by three other Zero fighters, he discovered that the airplanes were TBF Avengers because he clearly distinguished the top turret and the ventral machine gun. He shot down in flames two of the TBF Avengers and these two victories (61st and 62nd) were verified by the other three Zero pilots but during this day, no TBF Avengers were reported lost. This is an example how even an experienced pilot during the heat of battle, may not identify correctly enemy airplanes or receive verified credit for airplanes not shot down.

Sakai sustained grievous injuries from the return fire; he was struck in the head by a 7.62 mm (0.3 in) bullet, blinding him in the right eye and paralyzing the left side of his body. The Zero rolled over and headed upside down toward the sea. Unable to see out of his remaining good eye due to blood flowing from the head wound, Sakai's vision started to clear somewhat as tears cleared the blood from his eyes and he was able to pull his plane out of the steep seaward dive. He considered crashing into one of the American warships: "If I must die, at least I could go out as a Samurai. My death would take several of the enemy with me. A ship. I needed a ship." Finally, the cold air blasting into the c**kpit revived him enough to check his instruments, and he decided that by using a lean fuel mixture he might be able to make it back to the airfield at Rabaul.

Although in agony from his injuries (he had a serious head wound from a bullet that had passed through his skull and the right side of his brain, leaving the entire left side of his body paralyzed, and was left blind in one eye,) Sakai managed to fly his damaged Zero in a four-hour, 47-minute flight over 560 nmi (1,040 km; 640 mi) back to his base on Rabaul, using familiar volcanic peaks as guides. When he attempted to land at the airfield he nearly crashed into a line of parked Zeros but, after circling four times, and with the fuel gauge reading empty, he put his Zero down on the runway on his second attempt. After landing, he insisted on making his mission report to his superior officer before collapsing. His squadron mate Hiroyoshi Nishizawa drove him, as quickly but as gently as possible, to the surgeon. Sakai was evacuated to Japan on 12 August, where he endured a long surgery without anesthesia. The surgery repaired some of the damage to his head, but was unable to restore full vision to his right eye. Nishizawa visited Sakai while he was recuperating in the Yokosuka hospital in Japan."

now, are you ready to "man up" and give it another shot?  :D

try hardwiring the circuit on a breadboard or something, brute force, PC boards can be tricky, look for hairline shorts with a mag glass, sometimes when you bend the board a trace will open up, ohm out every trace, check circuit diagram again,

when you finally find it, your heart will soar like an eagle.

 

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what exactly is the problem? I don't seem to understand what your saying. if i understand you correct you have 2 X 1176 compressors. When using the same patch points one works and one doesn't. You are positive that it is between the XLR and the wiring going to the PCB?

If your 100% certain that is the case then maybe the fault has to do with broken traces and or missing solder pads...

 
I did for the first time recently. It's painful.

I should add, I was sort of forced into a situation where I can't afford replacement parts to try and I need something similar to use ASAP. I have to move on.

The battle is half the fun.
 
I have two Hairball/Mnats 1176's - a Rev A and a Rev D.  My Rev D is causing me the headaches... I know it's going to be something completely simple fix - there's not really much to the input circuit so i'm lost why I can't get it to fire up.  Of course, if I patch in my Rev A's input circuit and everything is hunky dory.  The problem being i'm only getting a very low signal of constant value that I can't shape in any way with the input knob.

Convinced it was a fault with either the input trafo or t-pad I bought another of each, replaced them both in the circuit with new wiring (new everything)... but nada.



I think i'm going to hand this off to an expert with broader troubleshooting skills, otherwise it'll be on the bench for the next 6 months rather than being put to use.
 
I would suggest taking a break. Give it a rest for a week or two, I usually come back to the forums and look at other people's builds (e.g. in my case Rev D builds). I see how great they are and it inspires me once again to finish the project.

If you ever find yourself rushing a build because you're excited to get it up and running, take a break for a bit and make sure that when you come back you've checked all your component values against the schematic/with a meter and make sure your wiring is correct. I know it's a pain and you just want things to be completed but I assure you it saves you a whole lot of hassle in the long run. Taking shortcuts is the worst thing you can do in DIY.

So my answer is no, I haven't admitted defeat. You can't admit defeat when you've sunk however many hundreds of dollars into a project. I don't know anyone that could fix this kind of project for me, besides... the amount of information you learn about the project along the way from troubleshooting is worth it.

Best of luck with your 1176.

Braeden
 
It's always the last thing you check, so only way to let it beat you is stop looking.  Think outside the box, if the obvious things aren't it, check un-obvious things.

JR
 
you know there is a really good part in the moog documentary where he talks about this very thing. When ever he ran into a problem he would just sleep on it and the answer would come to him.


edit you know you could run the working one and the one not working at the same time. Test and compare the working vs the one not working. You know an o-scope some tone and the other necessities.
 
As said before, take a break, don't think about it in a few days and the answer will come.

It works for me when I am tempted to give up.  I'm a newbie at electronics but all my started projects are working,  I had trouble some weeks ago with a power supply.  Finally I got help here and someone spotted the problem. I was using another psu then but at least I won't have that problem again
 
life is one big test, some tests are intense (see pilot story up above)
if you want a controlled test, try rock climbing without a rope, ???

there was a girl that swerved to avoid a deer on Hwy 70 and ended up in the Feather River. as here car was slowly sinking, she managed to pull herself together enough to pop the trunk hatch and rip out the back seat. since the trunk was in the air, she just climbed right out and swam to shore, do not know if i would have been able to figure that out under those conditions, you talk about a test, i bet she lives her life like there is no tomorrow,

the main man, who is good and evil, wants us to learn about ourselves by throwing a curve ball at us, what he wants us to learn is that you can always find a positive to every negative if you look real hard, but you have to look for it, as you get out of life what you put into it, you can try the karma approach, do something good for a stranger everyday, your karma points will go up  and he will then beam down the answer while you sleep,  ;)

and remember, the tougher the problem, the more joy you will feel after you solve it,

yeah i know, too much teddy bear talk can also make you feel sick,  ;D
 
Oh sure... I have a box full of Expat Audio designs that'll never see the light of day.

:)

Some of them I debugged for over a year, every few weeks... Others just never got built.

Even those that never saw the light of day, I consider to be a good learning experience.

/R
 
It is at that moment of despair that you have to be open to a break-through thought.  I can think of many times that I was ready to give-up on things and the solution was there if I was open to it.  I like to channel one of a number of awesome techs and look at things from their brain.  The other suggestions are well used also.

And if it's a kit pcb there is no excuse to give up!  What if you bypass the XLR and inject signal to the board?
Mike
 
pucho812 said:
you know there is a really good part in the moog documentary where he talks about this very thing. When ever he ran into a problem he would just sleep on it and the answer would come to him.
While that sounds a little mystical, in fact your brain can keep working on problems in the background while your foreground brain is occupied elsewhere.  My theory about dreams, is that it is housecleaning to make sense of unsorted impressions left over from the day, sometimes taking us in bizarre directions as we try to rationalize obscure or flawed input. 

For low tension tasks, without an immediate drop-dead deadline, sleeping on a problem is also good for reducing self imposed stress. I used to joke that my overnight engineering team would come up with some solutions for me.

When faced with a pressing deadline I have personally experienced a benefit from taking a short 4hr break to sleep. While I have pulled my share of all nighters when young, for doing brain work, you can't just will yourself to be sharp after too many hours on a task. I have woken up after a short sleep break refreshed and with answers, if not actual answers, new things to try. 
edit you know you could run the working one and the one not working at the same time. Test and compare the working vs the one not working. You know an o-scope some tone and the other necessities.
Yup, troubleshooting 101... compare node by node...  Sometimes the evidence is not obvious, but when chasing a lost signal check for AC and DC operating points.

JR
 
JohnRoberts said:
While that sounds a little mystical, in fact your brain can keep working on problems in the background while your foreground brain is occupied elsewhere. 

I can say that this is absolutely true for me as well.  On more than one occasion I have awoken in the early morning or even middle of the night and "realized" a solution to a problem.  Not so much that I dreamed the answer, but the background processing was going on for sure.

On the other side of the coin there is a guitar amp that I have owned since I was 15 (over 25 years now) and the tremolo has never worked.  I had a tech look at it before I knew anything about amps and he was not able to fix it.  I took a look myself within the past year, drew out the circuit (tube based, not opto) and measured everything.  There is no reason it should not work - all values are good, voltages fine, but the damn thing doesn't oscillate.  I decided it never has and maybe never will.  If I haven't needed it for this long...

 
Cj's posts - priceless! And I too can attest to what John and others have mentioned about sleeping on it and having the light bulb come on another day in a fresh state of mind. Chill man, if you're feeling pissed with it put it down and take a break for a bit - you'll get it sorted. It sounds like your close anyway, something with the input circuit or input wiring. Refuel, attack! (release, threshold - cut - not funny even - I need to go to bed myself...)
 
No! - never!
Seriously - yeah, at times, it's been disheartening but yah just gotta be patient and logical about sorting the problems!
There's projects i still have to finish but i'm sure i'll get there in the end.
If it's a project that others have successfully completed, then find them out and try to get help regarding your problems.
It helps others to help you if you can give a good description of the problem, and what you have done to remedy it!
If it ain't happening - then step back, take a break and go back to it with a fresh and clear mind.
One thing that has helped me to a great extent, is to get a good camera and take hi res pics of the build.
My eyes just ain't as good as they once were and after studying my pics of problems i've discovered things like micro solder bridges, the odd bad solder joint and even reversed signal connections off pcbs.
Just remember - if someone else has it working then the friendly bunch here will do what they can to help!
 
thanks for the props, the check is in the mail!

there is a simple but very effective method you can use to troubleshoot,

just get a hi-lighter pen or a white board marker and trace out the whole schemo til you find the problem,

learned this from a genius engineer i had the pleasure to work with,
 

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Well - i just read your post again and i don't know your input option.
Check this - i've been stumped before with FLOATING, BALANCED connections at both inputs and outputs.
If you have transformer input make sure the source driving it is indeed balanced or that your input tranny has one end tied to ground if running unbalanced!
On one DIY box output i made with floating tranny output - i sent the out to a little mixer to test which i assumed had balanced inputs.
When i finally gave up scratching my (now bald) head, i downloaded the mixer manual to find that the inputs i was using were unbalanced - i made the appropriate connecter change and BINGO - job was sorted!!
If this doesn't help then try and post some good pics of the problem areas
 

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