Whoho if I soldermask the whole board,I wont be able to solder anything..
No solder mask:
Little to expensive!!
Locking for another company them...
No solder mask:
no soldermask means $99 per panel, please confirm

Little to expensive!!
Locking for another company them...
Hi Ryssen,
I thought they were talking about a temporary coating. Not the green permanent one.
Another company indeed! Good luck, I'm sure there are reasonable companies close to you.
-Chris
Whoho if I soldermask the whole board,I wont be able to solder anything..

I thought they were talking about a temporary coating. Not the green permanent one.
Another company indeed! Good luck, I'm sure there are reasonable companies close to you.
-Chris
Stability problem SymAsym Clone
Hi,
I have been experimenting with the SymAsym Clone as presented in an earlier posting. I could get rid of the oscillation problem with some serious feedback capacitors on the compound stage but the bandwith dropped till appr. 150 kHz. So I decided to lose the driver for the compound(stage) and now de ampflier is perfectly stable onder all conditions.
Anatech: the compound has indeed "internal" gain, you are right about that. What i meant was the transfer from input to output exibits no voltage gain.
best regards,
Piersma
Hi,
I have been experimenting with the SymAsym Clone as presented in an earlier posting. I could get rid of the oscillation problem with some serious feedback capacitors on the compound stage but the bandwith dropped till appr. 150 kHz. So I decided to lose the driver for the compound(stage) and now de ampflier is perfectly stable onder all conditions.
Anatech: the compound has indeed "internal" gain, you are right about that. What i meant was the transfer from input to output exibits no voltage gain.
best regards,
Piersma
Attachments
Checkin if there is any interest in PCB´S for http://www.diyaudio.com/forums/showthread.php?s=&threadid=87609&perpage=10&pagenumber=16
http://www.diyaudio.com/forums/attachment.php?s=&postid=1085036&stamp=1166477983
As there are at least 2 persons here in sweden interested and more boards will of corse bring the price down,I´m checking!
Price are:
10 st/pcs = 2.300:-/230:-st/32,18 US dollar
16 st/pcs= 2.600:-/162,5:-st/22,74 US dollar
More than 16/lower price!!
Sign up!😎
http://www.diyaudio.com/forums/attachment.php?s=&postid=1085036&stamp=1166477983
As there are at least 2 persons here in sweden interested and more boards will of corse bring the price down,I´m checking!
Price are:
10 st/pcs = 2.300:-/230:-st/32,18 US dollar
16 st/pcs= 2.600:-/162,5:-st/22,74 US dollar
More than 16/lower price!!
Sign up!😎

I'd be interested in at least a couple. Can't figure out what those price figures mean.
Sheldon
Sheldon
If we order 16PCB´s then each pcb cost 22,74 US dollar.🙂
I´m allso wondering if there is a componentlayout for this board sommewhere.As it doesn´t seem to be a layout in the PCB zip.
I have e-mailed AAk but no answer...
I´m allso wondering if there is a componentlayout for this board sommewhere.As it doesn´t seem to be a layout in the PCB zip.
I have e-mailed AAk but no answer...
So far..
Myself 2
Sigurd 2
Sheldon 2 ?
SteveA 2 ?
I might take 2 more depending on he price.
Any more interested?
I´m in no hurry,so lets wait for more..🙂
Myself 2
Sigurd 2
Sheldon 2 ?
SteveA 2 ?
I might take 2 more depending on he price.
Any more interested?
I´m in no hurry,so lets wait for more..🙂
Hi Ryssen,
Got your email. Should have a parts placement diagram later today or tomorrow. The .slk zipped in post #161 shows where the parts go if you can display it. Either way I'll post it here.
Best regards,
Al
Got your email. Should have a parts placement diagram later today or tomorrow. The .slk zipped in post #161 shows where the parts go if you can display it. Either way I'll post it here.
Best regards,
Al
Hello
I have a minor question. The first differntial i fitted with a cascoded currrent source, but the second differntial is just biased with resistors. why is that. Is it to preserve the voltage swing capability. One should think bias stablilty, offest and PSR. would improve with a currint sink fitted.
I find it quite amazing how the two differntials seems to cancel all odd order distortion products. Nice
Michael
I have a minor question. The first differntial i fitted with a cascoded currrent source, but the second differntial is just biased with resistors. why is that. Is it to preserve the voltage swing capability. One should think bias stablilty, offest and PSR. would improve with a currint sink fitted.
I find it quite amazing how the two differntials seems to cancel all odd order distortion products. Nice
Michael
How about a nice compact power supply for the driver side of the board to run off the main transformer. Maybe a voltage doubler and a mosfet regulator. Won't need much current. Would a dual supply like this be a useful addition?
Sheldon
Sheldon
Here's the parts placement diagram for the board illustrated on page 16 (post #157) of this thread. You'll find the gerbers and bom on page 17. Hopefully it's clear enough to make out the labels. If not, let me know, I'll create a larger diagram and zip it.
Al
Al
Attachments
Current source
Hello Micheal,
My simulations show that a current source for the second diff.pair causes some slight increase of distortion. I haven't done some serious real life measurments yet. I think Mike has chosen the resistor for it's simplicity but I am not sure about that. You have to ask him.
best regards,
Piersma
Hello Micheal,
My simulations show that a current source for the second diff.pair causes some slight increase of distortion. I haven't done some serious real life measurments yet. I think Mike has chosen the resistor for it's simplicity but I am not sure about that. You have to ask him.
best regards,
Piersma
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