The ST reg is probably real, based on front side. The semi-circular notches on either side are absolutely required. So are the chamfered corners, which makes the power chip fake. But back side will tell - ST uses unique lead frames with peculiar shapes that not anybody can just go buy, so you can tell real from fake by looking at the data sheet. If the back side pattern does not follow exactly, it is a fake.
The regulator has got to be real, or it won’t supply an amp and a half peak current which you will need to swing 6 volts with a 4 ohm load. The power chip even if fake may not have a problem with only an amp and a half. If you do, get one by UTC.
Those old Motorola are what I like to see when buying outside of the distribution chain. It’s a part that has no market anymore other than the odd hobbyist, so you look for something that HAS been sitting on the shelf since 1989. They don’t sell much in the way of -8V regulators anymore so that one probably WAS surplus. If it were new and being presented as such I wouldn’t touch it with a 10 foot pole if it didn’t come from Mouser. There could still be enough volume to justify keeping +8’s around. Might be just enough for fakers too, so by all means check the package. ST makes that easy with their molded packages. TO-3’s too. They don’t make them anymore so if you run into a new date code ST 2N3055 it’s fake. They are all over the place now.
The regulator has got to be real, or it won’t supply an amp and a half peak current which you will need to swing 6 volts with a 4 ohm load. The power chip even if fake may not have a problem with only an amp and a half. If you do, get one by UTC.
Those old Motorola are what I like to see when buying outside of the distribution chain. It’s a part that has no market anymore other than the odd hobbyist, so you look for something that HAS been sitting on the shelf since 1989. They don’t sell much in the way of -8V regulators anymore so that one probably WAS surplus. If it were new and being presented as such I wouldn’t touch it with a 10 foot pole if it didn’t come from Mouser. There could still be enough volume to justify keeping +8’s around. Might be just enough for fakers too, so by all means check the package. ST makes that easy with their molded packages. TO-3’s too. They don’t make them anymore so if you run into a new date code ST 2N3055 it’s fake. They are all over the place now.
I'm affraid with what will happen in years to come :S Either use know good fakes, scrap components or move on to the newer technology.
I`m seating behind the desk right now, ready to do the power supply.
If TDA will be problematic, I will order and replace, thanks for the hint.
I never had problems with any IC from this store... so I`m holding my fingers crossed that it will be ok.
I`m sorry that I`m coming and going in intervals, but my baby girl needs attention.
If TDA will be problematic, I will order and replace, thanks for the hint.
I never had problems with any IC from this store... so I`m holding my fingers crossed that it will be ok.
I`m sorry that I`m coming and going in intervals, but my baby girl needs attention.
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NBD - it’s been almost a year now since I’ve been able to touch my audio projects. I’ve got a whole warehouse full of them to work on (literally), but the new facility is still under construction. None of it is going to get my full attention for at least another two years, and maybe January or February before any audio work gets resumed at all.
What I have figured out is the only way not to have constant home repairs filling up your time is to start over and Build It Right The First Time. Only then will everything stay fixed for more than 20 minutes.
What I have figured out is the only way not to have constant home repairs filling up your time is to start over and Build It Right The First Time. Only then will everything stay fixed for more than 20 minutes.
Will order genuine Ic and include it in my final build. I`m still thinking if I should break the ice and order PCBs for the first time, or just leave it on perfboards... I had bad feeling about perfoards until a member showed me full dolby prototype built on perfboard...
What are your thoughts about perfboards? ...I mean ofcourse in eyes of professional this probably looks silly, as some things looks silly to me in car workshop...
But all that aside, do you see any problems with using perfboards in audio circutry?
What are your thoughts about perfboards? ...I mean ofcourse in eyes of professional this probably looks silly, as some things looks silly to me in car workshop...
But all that aside, do you see any problems with using perfboards in audio circutry?
I totaly get you. My list of unfinished projects is getting longer and longer as I go... advice that I got from my boss was to stop worying, because I will never again be able to take a seat and say "I did it all".
Nice, no worries, either I will do ebay or find and scrap old sub.
For longer runs I just keep the insulation on. This was built up a piece at a time, over a period of months. The “amplifier” was just a generic test mule for a comprehensive set of protection circuits for much larger projects. Perf boards are the only way to do this sort of thing, because it evolves and changes.
