Ok thanks....on the "may require" some tuning....I looked at the many examples in the data sheet and see the inductor values and of course the zener values change. So when using 9 volts the zener in your bom is ok, but did you mean that these inductors might need changing? I guess there is a formula for these and any other parts that might need this type of tuning...
I dont have an real equipment here to look at signals etc, just a simple voltmeter..so I get a little paranoid with this stuff...
Alex
I dont have an real equipment here to look at signals etc, just a simple voltmeter..so I get a little paranoid with this stuff...
Alex
I meant more like freq compensation. To tune the feedback cap. Also I do not expect it to be significantly different from 3467. Even if it will be a bit off it is unlikely will have a significant impact on anything.
Can say there is a big chance it will be OK. Just don't forget to solder it the right way
Can say there is a big chance it will be OK. Just don't forget to solder it the right way
Done!
I just shipped Alex my bag of Crocodile parts that has been sitting here probably a year. I can see that I'm still just not going to get time to do any soldering anywhere in the near future, so much better these parts get used to build a Crocodile! Alex has the hot air soldering thing figured out now too from the AmpCasq project and he does great reviews.
All the parts should be there, including those special order coils.
Enjoy!
I cant thank you enough AGDR!!
I am looking over the schematic and reading all the thread posts once again!
I know Sergey designed this tiny amp without any I/O on the board to keep it small!
I will want to add all the normal I/O stuff eventually and get it into a nice small box. So any suggestions on the volume pot, any additional parts and wiring it in. I think Sergey mentioned to me that a linear 10K pot and adding 22-47pf caps to ground for emi protection on the inputs as well.
Looking at the board compared to Chris's amp, even though its smaller in overall physical size, the pads for most of the stuff dont look that hard to be able to solder paste etc...
Dont get me wrong they are still very tiny compared to most of the stuff we work with!
The chip density is high, I think I can most likely get many parts tacked down with paste and hot air a bunch of parts all at once, maybe in 2-3 passes..this way we keep the heat on the overall parts and board down to less heat cycles?
Looking forward to this challenge!
Alex
I am looking over the schematic and reading all the thread posts once again!
I know Sergey designed this tiny amp without any I/O on the board to keep it small!
I will want to add all the normal I/O stuff eventually and get it into a nice small box. So any suggestions on the volume pot, any additional parts and wiring it in. I think Sergey mentioned to me that a linear 10K pot and adding 22-47pf caps to ground for emi protection on the inputs as well.
Looking at the board compared to Chris's amp, even though its smaller in overall physical size, the pads for most of the stuff dont look that hard to be able to solder paste etc...
Dont get me wrong they are still very tiny compared to most of the stuff we work with!
The chip density is high, I think I can most likely get many parts tacked down with paste and hot air a bunch of parts all at once, maybe in 2-3 passes..this way we keep the heat on the overall parts and board down to less heat cycles?
Looking forward to this challenge!
Alex
adydula, good to see that you are alive and kicking
R146 and R147 change to 22-33Ohm was to reduce noise during powering up. With new values it was almost inaudible. Yes, you need to change both of them together.
See if it works in your case because I do not have a large enough sample to call it a "statistic"
R146 and R147 change to 22-33Ohm was to reduce noise during powering up. With new values it was almost inaudible. Yes, you need to change both of them together.
See if it works in your case because I do not have a large enough sample to call it a "statistic"
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Yes I am alive an will be 68 years young next month!!
I got my hot air gun working, completed Chris's amp and it worked first time, so I got the SMD small parts soldered with solder paste ok....wasn't that hard at all...but doing something new for the first time is harder just to get over the unknowns!! Ha!
AGDR is sending me his parts and I am ready to start on your crocodile!!
Good to hear from you again down under!
Alex
I got my hot air gun working, completed Chris's amp and it worked first time, so I got the SMD small parts soldered with solder paste ok....wasn't that hard at all...but doing something new for the first time is harder just to get over the unknowns!! Ha!
AGDR is sending me his parts and I am ready to start on your crocodile!!
Good to hear from you again down under!
Alex
It is good to try something new. Although fiddling with a heat gun not what people usually mean
Just to make you feel better - retirement age in Australia is pretty much 67
Can suggest to soled the PSU section first and make sure it is running OK. As an option - to do not load, on the begging, those resistors that connect amp to the PSU.
Just to make you feel better - retirement age in Australia is pretty much 67
Can suggest to soled the PSU section first and make sure it is running OK. As an option - to do not load, on the begging, those resistors that connect amp to the PSU.
Good idea! Chris suggested the same thing to me for his amp, which I did not do!! and lucky for me or my great soldering skills (lol) it worked first time!!
I will start with the PSU stuff and proceed.
My tact is to place as many parts in an area down with the solder paste and heat them all up vs one at a time and heat and reheat etc....this helps reduce the number of times I get the pcb and parts "hot"....
I will start with the PSU stuff and proceed.
My tact is to place as many parts in an area down with the solder paste and heat them all up vs one at a time and heat and reheat etc....this helps reduce the number of times I get the pcb and parts "hot"....
Too bad this amplifier uses so many SMDs. That really limits the number of people that can build and try it.
I don't mind soldering SOICs, but all those tiny resistors and caps aren't worth the hassle.
Seems the trend lately is "to see how small we can make the PCB for this project", hopefully 50mm x 50mm, so it qualifies for one of the Chinese board house's 5cm x 5cm special pricing offers.
This design could easily be put on a 10cm x 10cm board using thru-hole components including the LM6172s, which are still available in a DIP-8 package even though the OPA1611/1612 isn't.
Nowadays, 10cm x 10cm boards don't cost much more than the boards half their size.
I don't mind soldering SOICs, but all those tiny resistors and caps aren't worth the hassle.
Seems the trend lately is "to see how small we can make the PCB for this project", hopefully 50mm x 50mm, so it qualifies for one of the Chinese board house's 5cm x 5cm special pricing offers.
This design could easily be put on a 10cm x 10cm board using thru-hole components including the LM6172s, which are still available in a DIP-8 package even though the OPA1611/1612 isn't.
Nowadays, 10cm x 10cm boards don't cost much more than the boards half their size.
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