😀
It is obsolete now, but the FM radios used it a lot.
Changed the transformer on one a few days back...
1619 FM chip, plastic foil gang tuner, 810 amp, 4" speaker, bass treble circuit...must have been 20 years old.
The transformer was almost the price of the new radio 20 years back...
Now FM Module, and one channel of the stereo 6283 chip is common, why they cannot use a mono chip in a mono set is a mystery.
It is obsolete now, but the FM radios used it a lot.
Changed the transformer on one a few days back...
1619 FM chip, plastic foil gang tuner, 810 amp, 4" speaker, bass treble circuit...must have been 20 years old.
The transformer was almost the price of the new radio 20 years back...
Now FM Module, and one channel of the stereo 6283 chip is common, why they cannot use a mono chip in a mono set is a mystery.
The Datasheet shorts out half of the performance at pin2--See equivalent schematic, input 50k. There is a cap or RC missing (when single rail, the inputs need at least a cap, not a short). Perhaps keep that one datasheet page with equivalent schematic and pinout, but throw the other pages far? 🙂
Tripath chip amps... poor sounds almost instant failure. Likely because Fake chips were the only ones available. Garbage basically. No joy with 3116 chips either. Tried 3 different ones, finally tried the Fanboy claimed 'good one'. Replaced/upgraded most all the parts, as per Forum 'advise' . Yet it was still harsh / shrill /tinny sounding. Went into the trash bin.. deservedly.
LM3875. It has some very serious stability issues in all circuits I tried them in. I have had three exploding chips already which also blew up three drive units.
It’s a case where the cheapest and simplest possible implementation doesn’t work well. I’ve used the LM386 for all sorts of things over the years - a high fidelity listening system is NOT one of them, and it’s never the only semiconductor device in the system.
The power supply fluctuated while running the Tripath, thus releasing the stinky olive-color smoke. The newer fake version may have smaller die-shrank outputs so that it puts more of its power into heating itself, without that power serving the speaker. Gosh. These are less effective.
Maybe it is appreciable to 'clarify' home theater movie sound? However, for music replay, I've failed to appreciate it. With excellent thermals, these make their way into new cars, very tightly integrated. For this inconvenience, I'm thinking BSC's, such as 0.6 coil, 1uF, 20R, (speaker-level contour) so as to give the car's digital equalizer a fighting chance, possibly.
P.S. Try the TDA8932: Tone? Check. Voltage tolerance? Check.
Anything with a STK IC in it. Esp if its a replaced STK 99% of them in the market are fake. Many systems that use it have zero speaker protection.
I had a Sherwood that sounded VERY nice that uses a pair of STK1030... The protection was 3A fuses on the speaker outputs.
Least favourite would be most of the low power LM chips; either not enough power or I didn't have sensitive enough speakers. The Sanken SI-1020 modules deserve a mention; I blew up a pair of those.
There was an amp chip in a metal can package from Radio Shack that got reasonably loud through an 8" full-range; don't remember the part number. I liked the TBA810DAS; it was low distortion (according to the spec sheet), and it could swing the output closer to the supply rail thanks to a bootstrap capacitor, making it far more powerful than the LM3xx chips from the same supply voltage. So far I have no complaints about the ebay TA2024 amp board that I paid about $7 for (a bunch of years ago, so maybe not a fake) and have been using daily for over a year.
There was an amp chip in a metal can package from Radio Shack that got reasonably loud through an 8" full-range; don't remember the part number. I liked the TBA810DAS; it was low distortion (according to the spec sheet), and it could swing the output closer to the supply rail thanks to a bootstrap capacitor, making it far more powerful than the LM3xx chips from the same supply voltage. So far I have no complaints about the ebay TA2024 amp board that I paid about $7 for (a bunch of years ago, so maybe not a fake) and have been using daily for over a year.
When I first started using irs2092 I had all sorts of problems.
Couldn't even get it to come out reset to start with.
Sorted out close decoupling on 2092 and mosfets and at least then it ran.
Then had problems with resetting on high output levels.
Turned it up and it would reset.
Turned out to be poor mosfet gate drive.
I fixed it in 2 ways with gate driver IC but also found lower gate resistors helped.
Then turned 2092 off and got an almighty thump through the speaker.
Talked to IR about it and they said I had too much smoothing and it would need a reset circuit.
So came up with a simple PIC micro to hold 2092 in reset if VCC dropped too low.
It was fine after that but took a couple of pcb revisions to get there.
Learned a lot from that project.
Couldn't even get it to come out reset to start with.
Sorted out close decoupling on 2092 and mosfets and at least then it ran.
Then had problems with resetting on high output levels.
Turned it up and it would reset.
Turned out to be poor mosfet gate drive.
I fixed it in 2 ways with gate driver IC but also found lower gate resistors helped.
Then turned 2092 off and got an almighty thump through the speaker.
Talked to IR about it and they said I had too much smoothing and it would need a reset circuit.
So came up with a simple PIC micro to hold 2092 in reset if VCC dropped too low.
It was fine after that but took a couple of pcb revisions to get there.
Learned a lot from that project.
I made a car stereo amp with a pair of TDA2002s that wasn't half bad - it got replaced by a discrete design powered by a DC-DC converter that blew it out of the water...
Back then Cheap Cassette players using LA4440 was very popular in rural areas of india. But i never liked it. Instead my favourite amplifier ICs were LA4508 & TDA1557Q.
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Like I said the originals still have a cult following.
Which is why I got an amp based on the STK.The problem is with the STKs being sold in the market today.
STKs were always “roll the dice” as to whether they would last - and that was the real ones. Some died due to the usual problems like playing them too loud or running 4 ohms when they were used at the top end of their operating range. Some just quit when enough moisture got inside to upset things. Some lasted forever. Fakes would almost always die within hours, if they didn’t go up in flames the instant they were turned on - those don’t even count.