To complete the picture finally the measurements for the J-797 OPA.
And the comparison between the three.
Next step is to arrange an independent shootout between the three and the OPA627.
Patrick
.
And the comparison between the three.
Next step is to arrange an independent shootout between the three and the OPA627.
Patrick
.
No sir.
I know that schematics.
But I have different components and component values to suit the SMD design.
The one you posted is from the so-called HDAM, which is not unity gain stable.
But thank you for your interest,
Patrick
I know that schematics.
But I have different components and component values to suit the SMD design.
The one you posted is from the so-called HDAM, which is not unity gain stable.
But thank you for your interest,
Patrick
It was just a joke, but just looking at HDAM schematic...i wonder what's that thing that makes me believe it's unity gain stable....Is it because it runs at unity gain?
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For the PCBs, or fully finished or tested ?
For the PCB, you need to :
1) be able to solder 0603 and SOT363
2) be prepared to match SOT23-5 and SOT363 dual transistors
3) have a collection of susumu 0603 resistors for DC trimming
And of course you need a reasonable size to match from.
So you should be doing it for love of DIY.
🙂
Patrick
For the PCB, you need to :
1) be able to solder 0603 and SOT363
2) be prepared to match SOT23-5 and SOT363 dual transistors
3) have a collection of susumu 0603 resistors for DC trimming
And of course you need a reasonable size to match from.
So you should be doing it for love of DIY.
🙂
Patrick
Patrick,
I'd LOVE to buy finished & tested. At least a pair so I could try out.
I'd also be happy with PCBs & matched sets of transistors. BUT that's better after trying out, so I know it's worth the DIY'ing.
Buying the parts and soldering those sizes is not an issue for me
Greg in Mississippi
I'd LOVE to buy finished & tested. At least a pair so I could try out.
I'd also be happy with PCBs & matched sets of transistors. BUT that's better after trying out, so I know it's worth the DIY'ing.
Buying the parts and soldering those sizes is not an issue for me
Greg in Mississippi
I'll consider when I have time to make a few.
Would likely be a couple of months.
You can then try before you buy, but you need to pay postage both ways at least.
Will not be cheaper than commercial ones, as you would expect.
😉
Patrick
Would likely be a couple of months.
You can then try before you buy, but you need to pay postage both ways at least.
Will not be cheaper than commercial ones, as you would expect.
😉
Patrick
Patrick,
I know your work. I have used a couple of your ES9022 DAC boards and have a CEN/SEN kit on the workbench for a build to use with Ian Canada's ES9038Q2M RPi DAC board. ALWAYS GOOD, ALWAYS WELL THOUGHT OUT, ALWAYS A CLASS ACT.
I doubt I won't like them. Just want to try to see if I like them better than others.
AND I don't expect them to be cheaper than commercial ones at all. BUT I suspect they might be better. Again, I have some of your work... you can't do the small-job stuff as cheaply as a large batch after setup for production. AND when I DIY, is not cheaper either given my time... but I enjoy it and it helps keep me sane!
Later!
Greg
I know your work. I have used a couple of your ES9022 DAC boards and have a CEN/SEN kit on the workbench for a build to use with Ian Canada's ES9038Q2M RPi DAC board. ALWAYS GOOD, ALWAYS WELL THOUGHT OUT, ALWAYS A CLASS ACT.
I doubt I won't like them. Just want to try to see if I like them better than others.
AND I don't expect them to be cheaper than commercial ones at all. BUT I suspect they might be better. Again, I have some of your work... you can't do the small-job stuff as cheaply as a large batch after setup for production. AND when I DIY, is not cheaper either given my time... but I enjoy it and it helps keep me sane!
Later!
Greg
This thread is tempting me to try making a DIP8 adapter for my K2-X: GAP/R MODEL K2-X Socket for 12AX7 and 6AN8 Opamp | #141955721
though I suspect flashover might be an issue with those +/-300V rails, and it might be a tad top-heavy 🙂
though I suspect flashover might be an issue with those +/-300V rails, and it might be a tad top-heavy 🙂
> Patrick, 797 has bootstrapped Q5Q6 mirror, does your implementation has the same?
No. No Q12.
But it is a good point. I shall investigate advantage.
Thanks Dimitri,
P.
No. No Q12.
But it is a good point. I shall investigate advantage.
Thanks Dimitri,
P.
> 797 has bootstrapped Q5Q6 mirror, does your implementation has the same?
Tried it in Spice.
Distortion (mainly H2) reduces by a factor of ~10.
But trimming of DC offset is very sensitive.
So I think I would stay put for now.
Patrick
Tried it in Spice.
Distortion (mainly H2) reduces by a factor of ~10.
But trimming of DC offset is very sensitive.
So I think I would stay put for now.
Patrick
There are discrete clones of AD797 or something same as it in forum (folded cascode topology).
Member tiefbassuebertr who collected them at here: AD797 discrete clone - comparison of seven variations
Walkalone,
Member tiefbassuebertr who collected them at here: AD797 discrete clone - comparison of seven variations
Walkalone,
I'd like PCB's, I can solder those parts no problem.
Matching will be a challenge, but hey, that's part of the fun with diy, right?
Matching will be a challenge, but hey, that's part of the fun with diy, right?
> Matching will be a challenge.
> but hey, that's part of the fun with diy, right?
Designing PCBs is also part of the fun. 🙂
I posted enough photos that you can use as reference.
Patrick
> but hey, that's part of the fun with diy, right?
Designing PCBs is also part of the fun. 🙂
I posted enough photos that you can use as reference.
Patrick
Very true 🙂
It's my version of sudoku or something like that, doing layouts relaxes me.
Less than a tenth actually get fabricated, but it gives me something to do when my back prevents from being more active.