Informant OD and the TL072

[lifted diodes]

Hi all. I just recently discovered this site and I'm hooked. I'm building a cross contaminator right now and eyeing the informant OD next. I just have some questions.

I'm compiling my BOM cart for the informant (which I'd be happy to share once complete) and mouser states that the TL072 is obsolete. Can anyone recommend true equivalents or another place to find them in stock? And then that got me wondering if the TL072 is what is actually used in the "1891" (not sure if it's frowned upon to use the pedal name) or how precise the layout is. I found a single solitary gutshot of the "1891" and I'm seeing four ICs rather than the informant's three. I could be totally off but it just got me thinking. Has anyone built one of these yet? Any and all help is very much appreciated!

 

[Robert]

The TL072 is far from obsolete. The parts lists don't specify part number suffixes because there are several different variations depending on packaging style, temperature ranges, etc.

What you're looking for is the TL072CP.

TL072CP Texas Instruments | Mouser

TL072CP Texas Instruments Operational Amplifiers - Op Amps JFET Input Low Noise datasheet, inventory, & pricing.

www.mouser.com

The fourth IC you are referring to is a microcontroller for the relay, this is not part of the signal path.

 

[lifted diodes]

Thank you very much. I really appreciate it! Can I also use the "CP" suffix for the LT1054 or would there be a more suitable version?

The TL072 is far from obsolete. The parts lists don't specify part number suffixes because there are several different variations depending on packaging style, temperature ranges, etc.

What you're looking for is the TL072CP.

TL072CP Texas Instruments | Mouser

TL072CP Texas Instruments Operational Amplifiers - Op Amps JFET Input Low Noise datasheet, inventory, & pricing.

www.mouser.com

The fourth IC you are referring to is a microcontroller for the relay, this is not part of the signal path.

 

[Robert]

LT1054 CP or IP are both perfectly fine.

You can also use the even less expensive TC1044SCPA if you put a small blob of solder across the jumper pads on the back of the PCB.
(see the build docs for info)

 

[lifted diodes]

Great. I sincerely appreciate the help. I have searched the forums before posting so as not to be repetitive. But one more thing to finish sourcing my components: ideal lead spacing for non-electrolytic caps looks to be about 5mm if my scaling is correct...and looks like about 2mm for electros? is that a safe assumption? Trying to use all film caps so spacing is kind of important. Only value I couldn't find in 5mm film is 390pf but there's no schematic up for it yet though so I can't be sure if it's in the audio path. Ceramic should be ok at such a low value though no?

 

[Jovi Bon Kenobi]

Ceramic is fine for those values under 1nf. I like using MLCC's with a C0G/NP0 dielectric even better. Like THESE. For convenience they are already at 5mm spacing so no unbending the kinks.