I plan on comparing the datasheets for these two ICs but I believe that they are similar. Anyone has experience with either or both of them perhaps?
4136 type opamps are a quad of the humblest of all common opamps - uA741. Its datasheet states that it (XR4136) is a direct, pin-for-pin replacement part for RC4136. So was Fairchild's uA4136 and other clones. The RC... part of the number is a trademark so anyone cloning or otherwise supplying an alternative to the original (OEM) product, simply had to come up with a different part ID because that part number also identified the manufacturer, their product warranties, liabilities and other other corporate responsibilities.
It's likely that there are some minor differences between proper clones but what difference can it make now, between any of these low spec. opamps even if they are still in production somewhere? The important features of 741/4136 types is they are very cheap, work on single rail power supplies and can be configured to have no crossover distortion. This makes them ideal for tinkering about with sound effects for guitars but nowadays, not much more. There are several, much better quad opamps than either of these early 741 opamp types, but they likely wouldn't be easy to substitute in the 4136 circuit anyway. https://datasheetspdf.com/pdf/556919/Exar/XR-4136/1
I've also used and replaced the RCA product with Fairchild's in a few repairs, with no difference that I recall but that was many years ago! Apparently, Fairchild (now Onsemi) also later produced RC4136 branded product too: https://datasheetspdf.com/pdf-file/1305434/Fairchild/RC4136/1
It's likely that there are some minor differences between proper clones but what difference can it make now, between any of these low spec. opamps even if they are still in production somewhere? The important features of 741/4136 types is they are very cheap, work on single rail power supplies and can be configured to have no crossover distortion. This makes them ideal for tinkering about with sound effects for guitars but nowadays, not much more. There are several, much better quad opamps than either of these early 741 opamp types, but they likely wouldn't be easy to substitute in the 4136 circuit anyway. https://datasheetspdf.com/pdf/556919/Exar/XR-4136/1
I've also used and replaced the RCA product with Fairchild's in a few repairs, with no difference that I recall but that was many years ago! Apparently, Fairchild (now Onsemi) also later produced RC4136 branded product too: https://datasheetspdf.com/pdf-file/1305434/Fairchild/RC4136/1
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Hi Ian! Thank you for your detailed reply. I am using the 4136 in a Tapco 4400 since I think that one of the op-amps is iffy. Unfortunately I cannot substitute for a TL0741 since the pinout is different unless I build a daughter board.
Nobody said you substitute it by 741, only that it´s "741 class".
Yes, the datasheet mentions 741, only because way back then it was THE reference of standard to which all others were compared, nothing further.
In fact it´s a notch above, it´s the quad version of RC4558 which was the first widely available Op Amp designed for Audio, instead of instrumentation and such.
In fact it´s still widely available and used today, only it was slightly improved into 4560
Of course, we are talking a 1978 design here, well surpassed by modern offerings but still "usable" , at least in old equipment, such as your Tapco 4400.
Tapco was a semi-pro brand, catering to small recording Studios and "normal" band and Club PA systems.
I guess you are repairing one, in that case any of the variants will work fine.
Yes, the datasheet mentions 741, only because way back then it was THE reference of standard to which all others were compared, nothing further.
In fact it´s a notch above, it´s the quad version of RC4558 which was the first widely available Op Amp designed for Audio, instead of instrumentation and such.
In fact it´s still widely available and used today, only it was slightly improved into 4560
Of course, we are talking a 1978 design here, well surpassed by modern offerings but still "usable" , at least in old equipment, such as your Tapco 4400.
Tapco was a semi-pro brand, catering to small recording Studios and "normal" band and Club PA systems.
I guess you are repairing one, in that case any of the variants will work fine.
In general, second-sources from reputable manufacturers boast improved and tightened specs over the original, but this should be taken with a pinch of salt: by the time the second-source has appeared, the original manufacturer has had enough time to to refine his own processes, even if it not reflected in the DS.
Thus, the XR might have better specs than the RC ( I didn't care to check), but in reality they are probably equivalent, unless the original maker decided that the improvements deserved another denomination, like a suffix letter or even a different type number, in which case the the original parts would simply be "rejects", but they would still comfortably meet the DS limits
Thus, the XR might have better specs than the RC ( I didn't care to check), but in reality they are probably equivalent, unless the original maker decided that the improvements deserved another denomination, like a suffix letter or even a different type number, in which case the the original parts would simply be "rejects", but they would still comfortably meet the DS limits