I just completed a PCB layout for Graham's GEM amplifier and while on the job, I realised that 'noisy' and 'quiet' grounds can be separated by a 10 ohms 1 or 2 watt resistor. I wonder why Graham has suggested 'star ground' instead of a typically cleaner ground? Any comments?
Hi Samuel,
Them GEM has a large bandwidth, thus I protect against RF potential development at input wrt all ground commoned wiring.
Do try your suggested system, and let us know how you get on.
Cheers ........ Graham.
Them GEM has a large bandwidth, thus I protect against RF potential development at input wrt all ground commoned wiring.
Do try your suggested system, and let us know how you get on.
Cheers ........ Graham.
Yes, really i could see other wonderfull works too, made by Jan Dupont and Jens
Those boards always impressed me, the care he had to create, so small with so many decisions to avoid coupling and reducing size.
Thank you Peranders, i could see your example as wonderfull too.
regards,
Carlos
Those boards always impressed me, the care he had to create, so small with so many decisions to avoid coupling and reducing size.
Thank you Peranders, i could see your example as wonderfull too.
regards,
Carlos
Re: Graham and Barry are studying some good board, and they will test them
Oh yes,... this is not forgotten - i am looking forward to make two channel amp for myself when i finish what i have begun allready... 🙂 (few projects going)
best regards
sunny
destroyer X said:
Oh yes,... this is not forgotten - i am looking forward to make two channel amp for myself when i finish what i have begun allready... 🙂 (few projects going)
best regards
sunny
Ah, sigh...
So many amps, so little time...but with a pattern to etch, I may be able to coerce someone to dip a pair for me....hmmm...
So many amps, so little time...but with a pattern to etch, I may be able to coerce someone to dip a pair for me....hmmm...
Sunny and BQ40403, thank you by the presence.
Sunny...everybody loves Sunrise..you always welcome bringing all that ligth for us...happy to see you are doing some related this amplifier...you will be very happy with it.
Remember to place a Miller capacitor from base to colector... 33 to 68 picofarads capacitor, can be ceramic or Silver Mica....place it if you perceive that the zobel output filter (2,2 ohms in series with 47n) are overheating.... those components overheating are strong signs that you are having oscilations.... run to place the capacitor if needed.
BQ40403, those board are not checked in real life.... they were not assembled, sometimes problems appear...better to wait some days to have those boards checked.... very nice avatar, you may be a very interesting person....just because your choice related the image....because you apreciate that image, this means a lot (some positive things)...good to have you here.
regards,
Carlos
Sunny...everybody loves Sunrise..you always welcome bringing all that ligth for us...happy to see you are doing some related this amplifier...you will be very happy with it.
Remember to place a Miller capacitor from base to colector... 33 to 68 picofarads capacitor, can be ceramic or Silver Mica....place it if you perceive that the zobel output filter (2,2 ohms in series with 47n) are overheating.... those components overheating are strong signs that you are having oscilations.... run to place the capacitor if needed.
BQ40403, those board are not checked in real life.... they were not assembled, sometimes problems appear...better to wait some days to have those boards checked.... very nice avatar, you may be a very interesting person....just because your choice related the image....because you apreciate that image, this means a lot (some positive things)...good to have you here.
regards,
Carlos
Hi Carlos!
I have time to wait for others more qualified than I to proof the boards. I will find someone local to etch them for me.
Some things we need to view as if through Mongo's eyes. They appear in simpler terms, with no ill feelings. Its just how things are.
And Destroyer X's new avatar? I see the contemplation behind the curiosity leading to new discoveries...another side of the man. I like all the photos you have posted. This one says a lot.
I have time to wait for others more qualified than I to proof the boards. I will find someone local to etch them for me.
Some things we need to view as if through Mongo's eyes. They appear in simpler terms, with no ill feelings. Its just how things are.
And Destroyer X's new avatar? I see the contemplation behind the curiosity leading to new discoveries...another side of the man. I like all the photos you have posted. This one says a lot.
You are very sensitive La Fontaine.... i was thinking about all wonderfull things
I could have, and i could see and leave in my 54 years of life..... and my daugther made the image...I was watching the kids running and screaming, and remembering beautifull things.
Yes...the image expresses the rememberings i was having..... expresses the dream waken up.
Congratulations.... you are a natural analist.
regards,
Carlos
I could have, and i could see and leave in my 54 years of life..... and my daugther made the image...I was watching the kids running and screaming, and remembering beautifull things.
Yes...the image expresses the rememberings i was having..... expresses the dream waken up.
Congratulations.... you are a natural analist.
regards,
Carlos
Re: You are very sensitive La Fontaine.... i was thinking about all wonderfull things
Hi, I will put it first time before I run it - secure is secure 🙂 I am working to finish my started things and don't have much time - i have plans to do it that is for sure... i can't say when - as soon as i finish those projects i have started... 😉 🙂
Never mind - be happy 😀
nice picture...
destroyer X said:
Hi, I will put it first time before I run it - secure is secure 🙂 I am working to finish my started things and don't have much time - i have plans to do it that is for sure... i can't say when - as soon as i finish those projects i have started... 😉 🙂
destroyer X said:
Never mind - be happy 😀
nice picture...would these transformers work for the gem? Monoblocks
Serosmaness
http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=129-095
Serosmaness
http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=129-095
Hello Sunny, everybody loves Sunrise, welcome again, and hello Zero man "S"
Sunny, good conversation, i feel good when you are near...you are a positive guy... very charming person, making effort to be kind and will result in many friends.
Thank you Sunny, the apreciation of my picture...thank you.
....................................................................................................
Seromanass,or Zeromanass, ...very clever an interesting nickname.
Your transformer is wonderfull, as can be used to produce more than 75 volts each rail, having auxiliary voltages and good power.... will drive good power amplifiers.
In our case, the GEM, you are much more clever than average guys.... as you can use a variac or a 220 to 120 volts transformer plugget into your 120 volts outlet.... inputing half mains voltage to transformer, this way it will produce, after rectification and filtering around 37 plus 37 volts DC.... with 175 watts capability.
This power can be adequated to one GEM channel, as if you mind that two amplifiers like GEM have around 100 watts stand by current...but...when hard excited with audio, they will jump to higher consumption...... a little bit bigger than your transformer capacity...so, your voltage will reduce to 30 Volts plus 30 volts and your power to 35 plus 35 aproximatelly.
As you know, the 220 to 120 volts step down transformer have to be big in size and capacity...... and bigger than the power you will hold in the reality because of losses.... will be needed around 400 watts step down transformer...
Well, very clever, my calculations are from experience and damaged brain calculator, so...do not expect any precision related my idea...but i am sure Thousand Man Yes...your real value is more than Zero Man "S" or Zero Man Yes!!!
Congratulations
I am happy to perceive so extreme and exotic intelligence as you are showing me
regards,
Carlos
Sunny, good conversation, i feel good when you are near...you are a positive guy... very charming person, making effort to be kind and will result in many friends.
Thank you Sunny, the apreciation of my picture...thank you.
....................................................................................................
Seromanass,or Zeromanass, ...very clever an interesting nickname.
Your transformer is wonderfull, as can be used to produce more than 75 volts each rail, having auxiliary voltages and good power.... will drive good power amplifiers.
In our case, the GEM, you are much more clever than average guys.... as you can use a variac or a 220 to 120 volts transformer plugget into your 120 volts outlet.... inputing half mains voltage to transformer, this way it will produce, after rectification and filtering around 37 plus 37 volts DC.... with 175 watts capability.
This power can be adequated to one GEM channel, as if you mind that two amplifiers like GEM have around 100 watts stand by current...but...when hard excited with audio, they will jump to higher consumption...... a little bit bigger than your transformer capacity...so, your voltage will reduce to 30 Volts plus 30 volts and your power to 35 plus 35 aproximatelly.
As you know, the 220 to 120 volts step down transformer have to be big in size and capacity...... and bigger than the power you will hold in the reality because of losses.... will be needed around 400 watts step down transformer...
Well, very clever, my calculations are from experience and damaged brain calculator, so...do not expect any precision related my idea...but i am sure Thousand Man Yes...your real value is more than Zero Man "S" or Zero Man Yes!!!
Congratulations
I am happy to perceive so extreme and exotic intelligence as you are showing me
regards,
Carlos
Mr. Barry Husbands, a very nice guy, has been working with Graham Maynard
And some schematic and board was already shown...and i told you before that was not constructed yet.
I continue to say the same, as i was not informed by Graham or by Barry that the board was constructed, circuit assembled and tested over this board was not made till today.
So, this will be next step.... and i will be waiting, understanding the both have not conditions to make those things too much fast.
Mr. Barry informed that as soon as he can find time, he will inform us the complements, alike part lists...very organized and very cooperative Mr. Barry, you always welcome with that sense of cooperation.
Here is the Barry's produced schematic.
regards,
Carlos
And some schematic and board was already shown...and i told you before that was not constructed yet.
I continue to say the same, as i was not informed by Graham or by Barry that the board was constructed, circuit assembled and tested over this board was not made till today.
So, this will be next step.... and i will be waiting, understanding the both have not conditions to make those things too much fast.
Mr. Barry informed that as soon as he can find time, he will inform us the complements, alike part lists...very organized and very cooperative Mr. Barry, you always welcome with that sense of cooperation.
Here is the Barry's produced schematic.
regards,
Carlos
Attachments
Here is the board, it has a lot of copper material producing some ground plane...so,
You can have another board, without those black copper ground planes, the other one, already published in this thread, will turn easier to see all the parts positioned.
Remember to check everything, as we are humans, and it is not impossible, for humans, to produce mistakes.
Observing and studying Universal Human Hystory, you will see that we made an enormous sequence of errors...so... this is something very expected.... some mistake can happen, reason why i am telling you that was not constructed.... and during construction, some error may appear.
Thanks to Barry again.
regards,
Carlos
You can have another board, without those black copper ground planes, the other one, already published in this thread, will turn easier to see all the parts positioned.
Remember to check everything, as we are humans, and it is not impossible, for humans, to produce mistakes.
Observing and studying Universal Human Hystory, you will see that we made an enormous sequence of errors...so... this is something very expected.... some mistake can happen, reason why i am telling you that was not constructed.... and during construction, some error may appear.
Thanks to Barry again.
regards,
Carlos
Attachments
- Status
- Not open for further replies.