Reddish 500 EQ

[dmp]

Post some pictures, front and back

 

[Forcemusicgroup]

Sorry for the delay in response. Its weather is horrible here currently. Im just now getting home so Im more prompt. I'll take pics right now. Thanks for your support. Let me know if you need me to take pics of anything specific as well.

 

[Forcemusicgroup]

 

[Forcemusicgroup]

 

[MidnightArrakis]

View attachment 145193

[This is a -- purchased -- PCB?] -- From what little I have read here in this thread about the problem you are experiencing with one of your PCB's, I am guessing that you have -- purchased -- this PCB from someone else on this forum? If not, do you have the GERBER files from which this PCB was fabricated from? If so and you could PM me, I could run them through one of my "GERBER & N/C Drill Data Analysis & Editing" programs, which may possibly point to an error that could possibly causing your problem. More than likely, from what I have seen here in your fuzzy photo, there's a "solder-bridge" somewhere shorting something out.

Again.....since your photo is rather fuzzy and out-of-focus making it difficult to see things clearly, from what I am able to kind of see, some of the soldering is borderline "iffy" at best, some of the solder-blobs' discoloration tells me of a possible "cold solder joint" here and there and because of the photo being out-of-focus and it's difficult to clearly define what it is that I am seeing.....it also appears to me as though some of the "Copper Pour" areas seems to be "Isolated-Copper" areas. But, running these GERBER and N/C Drill Data files through my "GERBER Analysis" program would instantly disclose any potential fabrication errors within these files.

>> The top component pad of R22 doesn't look as though it is soldered. Dunno.....

GOOD LUCK!!!

/

 

[ruffrecords]

I agree some of the soldering could be better. It might be worth while touching up the joints around the IC at least.

Cheers

Ian

 

[JMan]

I agree with Ian and MidnightArrakis, retouching the solder joints around the IC would be a good next step.

[...]it also appears to me as though some of the "Copper Pour" areas seems to be "Isolated-Copper" areas.

The copper pours were placed with care and intention and all of them have a low impedance path to the relevant ground pad (audio or power) on the edge connector. As you said, though, that isn't necessarily easy to see in the photo.

 

[inf0]

@JMan I am about to assemble the unit in the metalwork , just wanted to double check :

Since I'm using the L bracket from Kevin , do I only need to file down the powder coating on the top transformer mounting hole?
I remember reading something about that in the thread but I'm not sure if i should do it to every mounting hole

Thank you !

 

[JMan]

@inf0 you should only need to file the powder coating from the top transformer mounting hole, as that is where the L bracket has its electrical connection to the Chassis pin on on the edge connector. Once you do that and get it mounted, a quick continuity check or impedance measurement between the L bracket and that pin (pin 1) on the card edge will tell you if you've got a good connection.

 

[inf0]

@inf0 you should only need to file the powder coating from the top transformer mounting hole, as that is where the L bracket has its electrical connection to the Chassis pin on on the edge connector. Once you do that and get it mounted, a quick continuity check or impedance measurement between the L bracket and that pin (pin 1) on the card edge will tell you if you've got a good connection.

Appreciate it! Thank you

 

[dmp]

@Forcemusicgroup
I'd suggest rechecking all your solder joints. Then, trace the signal path with a multimeter (or signal gen/scope if you can), following the schematic.
You may have to pull the IC, install a socket, and replace it. It's not worth saving $0.50 to skip the IC socket. But I would trace the signal path first

 

[dmp]

@MidnightArrakis
This PCB is known to work well - if you read this thread you would know that - in fact - it is one of the nicest designed PCBs I've seen on this forum. @JMan has done an excellent job and has shared something excellent with the DIYers here. No one who has put so much work into developing a project like this wants to give you the Gerbers. Go develop your own project here to understand what it takes - instead of going into threads and criticizing.

 

[Forcemusicgroup]

I apologize for the pictures being blurry, I took the pics on a iPhone 16 pro max. Maybe the site encoded it due to its size.

I'll try something different. Meanwhile Ill touch the joints removing some of the extra solder "added for easy removal" Ill touch back once finished.

 

[Forcemusicgroup]

[This is a -- purchased -- PCB?] -- From what little I have read here in this thread about the problem you are experiencing with one of your PCB's, I am guessing that you have -- purchased -- this PCB from someone else on this forum? If not, do you have the GERBER files from which this PCB was fabricated from? If so and you could PM me, I could run them through one of my "GERBER & N/C Drill Data Analysis & Editing" programs, which may possibly point to an error that could possibly causing your problem. More than likely, from what I have seen here in your fuzzy photo, there's a "solder-bridge" somewhere shorting something out.

Again.....since your photo is rather fuzzy and out-of-focus making it difficult to see things clearly, from what I am able to kind of see, some of the soldering is borderline "iffy" at best, some of the solder-blobs' discoloration tells me of a possible "cold solder joint" here and there and because of the photo being out-of-focus and it's difficult to clearly define what it is that I am seeing.....it also appears to me as though some of the "Copper Pour" areas seems to be "Isolated-Copper" areas. But, running these GERBER and N/C Drill Data files through my "GERBER Analysis" program would instantly disclose any potential fabrication errors within these files.

>> The top component pad of R22 doesn't look as though it is soldered. Dunno.....

GOOD LUCK!!!

/

im not the designer. Im sure he's here somewhere. He may be okay giving the files to you. Not sure. REsolded R22

 

[Forcemusicgroup]

Ok. so I've went ahead and resoldered literally every joint. Still met with no audio out when active. @JMan Please advise. Taking new Photos

 

[JMan]

im not the designer. Im sure he's here somewhere. He may be okay giving the files to you. Not sure. REsolded R22

Yes, he may be here somewhere *cough cough*

Ok. so I've went ahead and resoldered literally every joint. Still met with no audio out when active. @JMan Please advise. Taking new Photos

Did you check for continuity between IC Pin 8 and the +16v pad on the card connector as I suggested at the end of our exchange last night?

We need to figure out why there is no positive voltage reaching the op amp. If resoldering fixed that issue and we still don't have audio, then we will need to start tracing the signal through the audio path. But let's figure out that voltage issue first.

 

[Forcemusicgroup]

New pics

 

[capacitorless]

I think more measurements are more important than more photos. But I'm just a bystander.

@JMan I just looked at the build document in detail. Great work (and support)!

 

[Forcemusicgroup]

Yes, he may be here somewhere *cough cough*

Did you check for continuity between IC Pin 8 and the +16v pad on the card connector as I suggested at the end of our exchange last night?

We need to figure out why there is no positive voltage reaching the op amp. If resoldering fixed that issue and we still don't have audio, then we will need to start tracing the signal through the audio path. But let's figure out that voltage issue first.

Still no connection between pin 8 and +16v pad. Using a fluke 117

 

[inf0]

Possible solder bridge?