Substitute TL002 for TL019

[Esppse]

Hello,

I'm trying to build the Octave Clang.

https://2.bp.blogspot.com/-MQzlG2dD6QY/WmB-o6dMyCI/AAAAAAAABpU/-2u9OhX_w5sdzp-EWpKLVmcJrv7j9cx6QCLcBGAs/s1600/Death%2BBy%2BAudio%2BOctave%2BClang.png

I don't have a TL002 and it's current backordered from Mouser. Can I replace it with the TL019? According to this chart, the numbers are extremely similar.

http://s268.photobucket.com/user/Madaboutbed/media/DogAndPony/Trafos_mouser_zpsdc64nj3z.png.html

Thanks

[rankot]

You can surely use 42TM002, it is also 10k:2k transformer.

[Esppse]

Are the TM series bigger? If they are, I didn't allocate proper space since I actually modified the strip board a bit of a customized fitting.

[rankot]

They have bigger core.

[Esppse]

OK I struggled with this build a bit. The 42TL019 is verified to work. It seems that the reason thus circuit is hard to get working is the 741 chip. I tried 2 different variants, 1 failed produce sound. The second worked perfectly.

[rankot]

As far as I understand this, you can use any TF with 10k impedance. If it is asymmetrical (10k:2k or 10k:600, for example), you must take care to use 10k side in this circuit.

[highwater]

It seems that the reason thus circuit is hard to get working is the 741 chip. I tried 2 different variants, 1 failed produce sound. The second worked perfectly.

The non-inverting input is left floating, and pin 4 (one of the null offsets) is grounded... I only vaguely understand how that's supposed to work*, but the internal circuitry is definitely *not* designed to be used like that, and may in-fact be completely different than the "simplified schematic" in the datasheet.

This is one of those rare instances where a particular brand and/or vintage of opamp actually *can* have mojo.

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*: I can't find it right meow, but I've seen a PDF that discussed non-standard uses of offset null pins. They mentioned in passing that the 741 has higher gain at the offset null pins than the actual inputs (with, I assume, a dreadfully low input impedance).