I put that in so that you gentlemen would have something to take out.
Said by me and 100% correct. NEVERTHELESS I will pay USD 100. to the first person who correctly identifies an earlier publication of the exact same sentence in mainstream literature. Google Advanced Search is a waste of time (I claim).
Said by me and 100% correct. NEVERTHELESS I will pay USD 100. to the first person who correctly identifies an earlier publication of the exact same sentence in mainstream literature. Google Advanced Search is a waste of time (I claim).
Here you go:
https://www.diyaudio.com/forums/vendor-s-bazaar/283672-audio-op-amp-opa1622-16.html#post4656236
N. Wolfe says to the League of Frightened Men (p.40)
Google search not that bad after all!
A clever fellow had already given the answer here in this very forum!
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Thanks grataku
The turned off channel was still shorted at the input and the tested channel was connected to the output from the soundcard.
I didn't check the current but under load I have +/- 21.3V voltage on both channels. IMHO there will be unevenness between channels whenever one channel is turned off.
I have already swapped the power sides and it did not matter.
Probably I will not do much more today because I feel unwell after the anti-covid vaccination.
It may be common in our diy audio world and some generous people may like to just quietly go about being generous but I’d like to thank one of them on the forum.
Some way back in this thread Ryssen kindly offered to share excess IPS6 and IPS7 boards and I took him up on the offer as, thanks to the pestilence, getting boards from China to where I live was proving impossible - it’s now well past a year that some I ordered haven’t shown up. Ryssen’s IPS6 and 7 from Europe took a month.
Today, out of the blue, a little envelope showed up with two Cedarburg input boards. Thank you, Ryssen. If you ever make it to my Rock, the rum is on me.
(they were mailed March 15th!. Shall now place another Digikey order and....wait patiently.)
Some way back in this thread Ryssen kindly offered to share excess IPS6 and IPS7 boards and I took him up on the offer as, thanks to the pestilence, getting boards from China to where I live was proving impossible - it’s now well past a year that some I ordered haven’t shown up. Ryssen’s IPS6 and 7 from Europe took a month.
Today, out of the blue, a little envelope showed up with two Cedarburg input boards. Thank you, Ryssen. If you ever make it to my Rock, the rum is on me.
(they were mailed March 15th!. Shall now place another Digikey order and....wait patiently.)
Thanks grataku
The turned off channel was still shorted at the input and the tested channel was connected to the output from the soundcard.
I didn't check the current but under load I have +/- 21.3V voltage on both channels. IMHO there will be unevenness between channels whenever one channel is turned off.
I have already swapped the power sides and it did not matter.
Probably I will not do much more today because I feel unwell after the anti-covid vaccination.
I have had vaccine side effects as well after the second shot. They lasted 24 hrs.
Why should there be unevenness in output noise?
I think Rafa is more in "need" in getting a proper 2 channel 50meg scope on the cheap to work on his stuff than 100 bucks.. no offense, it's not of my business anyway...but well done Rafa
Its just that Mark puts the money where the mouth is (or something like that) while providing both excellent content and entertainment.
Anyways, Rafa can use the help with his VFET shipping cost. I hard they were out of control for him.
I meant the unevenness of the power supply. That's just my guess. The voltage on the unloaded PSU is around +/- 23V.I have had vaccine side effects as well after the second shot. They lasted 24 hrs.
Why should there be unevenness in output noise?
Why not measure voltage drop across the crc resistor one channel at a time and figure if the channels draw diff current?
I know these are rather mundane measurements but I see no reasons why channels should output different 100Hz values, or any 100Hz at all..
I think Rafa is more in "need" in getting a proper 2 channel 50meg scope on the cheap to work on his stuff than 100 bucks.. no offense, it's not of my business anyway...but well done Rafa
Its just that Mark puts the money where the mouth is (or something like that) while providing both excellent content and entertainment.
Anyways, Rafa can use the help with his VFET shipping cost. I hard they were out of control for him.
Hey! Thanks so much all for thinking of me and my specific condition... it demonstrates that this community is mostly based on people and you are paying as much attention to the human side as you are to the technical side, so I am really moved! Thanks!
I am not planning on cashing this particular chip at all. Mark himself had given the answer and it did not come from me knowing the reference! Also, I feel that Mark has given to the community more than enough as to cash this in.
I may yet kindly ask for PCBs for the VFET front ends as local printing is really sub-par, but that will require also importing logistics, which, as noted, are already crazy with the VFet parts and chassis on route... so I will keep this chip as a nice fun story and perhaps someday I can abuse Mark's generosity with his PCBs.
Thanks!
Rafa.
paralleling 0.5x3 you get 0.17 ohms
I=V/R =0.225/0.17=1.32A which is what it should be the right current for each channel.
So powering one channel at a time and using the same PS side has no effect on the noise?
I've run into a snag. Thanks to Twichie I have some 1612A's mounted on SOIC to DIP adapter boards. The challenge I have is the sockets I've installed
https://www.mouser.ca/datasheet/2/273/090-259652.pdf. They'll only accept headers with square pins in the .015-.018 range. all headers I've come across so far have pins that are .025 square.
So it's a case of a socket with larger holes or headers with smaller pins?
Regards,
Dan