Correct, you would have to cut the trace on the board connecting the other input cap to ground and instead use it for the negative of the differential input.
the positive chip input which is labelled - on your pcb's needs to be tied to gnd on inputs right of where you connected your source, did you understand that from my earlier post or did you miss the post ?
STOP
Irribeo,
Do you mean post #372? Your edit to that post?
If so, how about a more detailed explanation, a sketch...something.
Time for a little rant (sorry):
Listen, I hate to single you out, and I'm not, because generally I find your posts very helpful.
But people on these forums have got to start being more clear about:
1) What exactly they are referring to. Who are they addressing? Which post? Which question? Which comment?
2) Making sure their facts/findings are right before they post. Everybody makes mistakes, but a simple proofread of your post would be helpful. Some of us take your word as truth and look to those of you with more knowledge for help.
3) Posting a photo, a quick but clear sketch of what they mean.
4) STOP, STOP, STOP using stupid abbreviations like "trafo" for transformer, IMO for in my opinion or other cute internet-speak, cell phone speak, or corporate-speak terms. Are we not still using English? Newbies? Tooooooo cutesy? Beginners perhaps? Neophytes perhaps. Pick a real word from the dictionary. And learn how to spell it.
There are a lot of beginners on this forum and a lot of foreigners who are not tuned in to all this secret lingo/language/jargon. Referring to a 4.7K ohm resistor? Would it kill people to write that instead of 4K7R? And for example when referring to a necessary capacitor or resistor, would it kill people to also explain what voltage or wattage is needed.
5) Finally....like I say, I realize there are a lot of foreigners here and I except you from this part of the rant since your English skills may not be as good as native speakers; but could people start spelling stuff correctly? There vs. their. Through vs. threw. Your vs. you're. Spelling the word resistor wrong. Come on! Resistor should never be spelled resister and especially on a DIY electronics forum. Use of the "word" Newbies? Tooooooo cutesy! Are we 9th grade Valley Girls? The word is beginners. Neophytes perhaps, or inexperienced. Stop all this.
It's getting so you can barely understand some of these posts with all the incomplete sentences, misspellings, and references to who knows what post?
6) Civility would be nice.
7) THINK before you post. Slow down. Think if you are making any sense to someone less experienced, or someone who is not a native English speaker.
Don't be in such a hurry to post your message and show off your perceived superior knowledge to the rest of us. This seems to be important on some forums. The "I'm so smart and you're so stupid" mentality. Not as much here, but still there is some of this.
Please show a little consideration to us who are trying to learn from you. Your knowledge, experience, and guidance is greatly appreciated. But if we can't understand it -- it's wasted bits and bytes. The post you make is permanent. I've found posts of mine from years ago with a Google search (kind of scary). So, if a post has incorrect information in it, well that's permanent as well.
The threads get to be hundreds of posts long and clogged with the questions of people who (like me) don't quite understand what someone is referring to, or understand.
I'm climbing down from my soapbox now,
MW
Irribeo,
Do you mean post #372? Your edit to that post?
If so, how about a more detailed explanation, a sketch...something.
Time for a little rant (sorry):
Listen, I hate to single you out, and I'm not, because generally I find your posts very helpful.
But people on these forums have got to start being more clear about:
1) What exactly they are referring to. Who are they addressing? Which post? Which question? Which comment?
2) Making sure their facts/findings are right before they post. Everybody makes mistakes, but a simple proofread of your post would be helpful. Some of us take your word as truth and look to those of you with more knowledge for help.
3) Posting a photo, a quick but clear sketch of what they mean.
4) STOP, STOP, STOP using stupid abbreviations like "trafo" for transformer, IMO for in my opinion or other cute internet-speak, cell phone speak, or corporate-speak terms. Are we not still using English? Newbies? Tooooooo cutesy? Beginners perhaps? Neophytes perhaps. Pick a real word from the dictionary. And learn how to spell it.
There are a lot of beginners on this forum and a lot of foreigners who are not tuned in to all this secret lingo/language/jargon. Referring to a 4.7K ohm resistor? Would it kill people to write that instead of 4K7R? And for example when referring to a necessary capacitor or resistor, would it kill people to also explain what voltage or wattage is needed.
5) Finally....like I say, I realize there are a lot of foreigners here and I except you from this part of the rant since your English skills may not be as good as native speakers; but could people start spelling stuff correctly? There vs. their. Through vs. threw. Your vs. you're. Spelling the word resistor wrong. Come on! Resistor should never be spelled resister and especially on a DIY electronics forum. Use of the "word" Newbies? Tooooooo cutesy! Are we 9th grade Valley Girls? The word is beginners. Neophytes perhaps, or inexperienced. Stop all this.
It's getting so you can barely understand some of these posts with all the incomplete sentences, misspellings, and references to who knows what post?
6) Civility would be nice.
7) THINK before you post. Slow down. Think if you are making any sense to someone less experienced, or someone who is not a native English speaker.
Don't be in such a hurry to post your message and show off your perceived superior knowledge to the rest of us. This seems to be important on some forums. The "I'm so smart and you're so stupid" mentality. Not as much here, but still there is some of this.
Please show a little consideration to us who are trying to learn from you. Your knowledge, experience, and guidance is greatly appreciated. But if we can't understand it -- it's wasted bits and bytes. The post you make is permanent. I've found posts of mine from years ago with a Google search (kind of scary). So, if a post has incorrect information in it, well that's permanent as well.
The threads get to be hundreds of posts long and clogged with the questions of people who (like me) don't quite understand what someone is referring to, or understand.
I'm climbing down from my soapbox now,
MW
Last edited:
Addition to nice list: Most forumrules will tell you not to use "quote" in next post, datalimits etc.
Point taken!
OK,, I didn't realize that.
Clarity should always be paramount however.
Thanks,
Mark
OK,, I didn't realize that.
Clarity should always be paramount however.
Thanks,
Mark
For prezden the way to connect inputs on his pcbs should be clear, if he wishes to draw his pcb, I guess he will invest time into doing that, I will not stop him. I don't think there is a general interest served in clarifying these pcbs he owns/bought, there aren't that many other buyers of that pcb asking for help here, I cant remember anybody actually, and I do remember JeanPaul the moderator posting he found these on some Taiwanese website, years ago🙂
OT:
So true. It really annoys me when using Tapatalk and people now an then do full quotes. Even more annoying when they just answer to one post up. Maybe this is a leftover from the newsgroups. 🙂
@Mark2727,
4k7R vs. 4.7k Ohm (or 4,7k Ohm in europe)
To me 4k7R is more clear, that notation is easy to learn. You may want to give it a try, makes life easier as for:
1u5F, 8u2H, 0R15 - not to worry about "." and ",".
Just my thoughts. 🙂
So true. It really annoys me when using Tapatalk and people now an then do full quotes. Even more annoying when they just answer to one post up. Maybe this is a leftover from the newsgroups. 🙂
@Mark2727,
4k7R vs. 4.7k Ohm (or 4,7k Ohm in europe)
To me 4k7R is more clear, that notation is easy to learn. You may want to give it a try, makes life easier as for:
1u5F, 8u2H, 0R15 - not to worry about "." and ",".
Just my thoughts. 🙂
Prezden,
Don't be sorry at all. This place is for learning! And asking questions!
I'm just frustrated because I saw your post, and had the very same questions. I saw that same board a few weeks ago and wondered the same thing.
And I still don't get what the answer is. It's no doubt an easy answer, but not being explained well.
Best,
Mark
Don't be sorry at all. This place is for learning! And asking questions!
I'm just frustrated because I saw your post, and had the very same questions. I saw that same board a few weeks ago and wondered the same thing.
And I still don't get what the answer is. It's no doubt an easy answer, but not being explained well.
Best,
Mark
To answer this in "irribeo style",
Ti datasheet says:
BUT, on your board the negative input (at the IC pin 5) is connected to (+), while the positive input (at the IC pin 4) is connected to (-).
So you wanna first just swap your soldered leads and, if this isn't doing any good, then soldering a bridge from the (+) pin to the middle (GND) pin as irribeo sayed.
If there's still residual noise after this mod, chances are good that both boards interfere with each other over their shared power connection.
Regards.
For those who care: doctormord suggests to swap your soldered leads first, with that you connect negative chipinput to source gnd and source signal to ampboard gnd. If this isn't doing any good he suggests to connect the other chipinput to ampboard gnd too.
Just for clarification, and good luck prezden!
Just for clarification, and good luck prezden!
It does seem I did in my recent posts, did you consider the connections he made already were signal to negative input and source gnd to ampboard gnd, swapping those would mean source gnd to negative input and source signal to ampboard gnd.
That would be the correct way to connect it, as TI says. The Taiwanese suggested option is in silkscreen + labels and is inverted, but basicly the same, bridge/jumper from - to gnd, signal to + silklabel , source gnd to ampboard gnd, prezden started the taiwanese inverted way but didn't gnd/jumper the other chipinput.
Hi folks, I just discovered something very cool and a money saver for diy amp builders. In the past, I buy my very specific parts from a traditional electronic parts supplier like DigiKey, Mouser, Newark Electronics, etc. They have massive inventory and a lot of stuff in stock. However, you pay a premium for the convenience and availability with quick delivery. Also, I don't always need the best name brand of some part. For many bypass caps, if it is a 0.1uF 100v metalized foil cap, I don' t care who makes it. Normally I just buy whole amps or amp kits from Aliexpress. This time, I needed a bunch of odd power resistors like 33R 5w, 3.3R 2W, 2.2k 2w, etc. try typing that into the search window. Bang! You get a lot of hits. It works better than the search engines on Digikey because it finds thousands of vendors who will sell you 10pieces, 50pieces, 1000pieces, etc. all free shipping. The magic is then the sorting buttons. Click "Free Shipping" and sort low to high.
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This is hobby, so I don't mind waiting 2-3wks for my parts to arrive. It's not a big deal to me. Most of the time the stuff shows up before I am ready to actually build.
You are presented typically with an option like 10 pieces of whatever for $0.67 to $1.50 with free shipping. I saved a bundle and have enough spare parts to make like 5 or 10 assemblies.
This is hobby, so I don't mind waiting 2-3wks for my parts to arrive. It's not a big deal to me. Most of the time the stuff shows up before I am ready to actually build.