I built two circuits as similarly as possible 1) quad ua741 and dual NE5532. FFT on my Rigol scope showing peaks at 1k and 15k as set/expected (2 channels from Seesil generator are mixed with 1k signal at 80% of 15k signal amplitude) with this I believe I created a tool to do AM with my cheap Seesil generator and can also mix two audio signals.

That said, I have no clue what I am doing. I based my testing procedure off an Elenco radio kit.

So I guess I actually have two questions or areas where I am trying to understand better:

1. What makes one op-amp better than another? I am talking about the IC itself, I believe. Why is NE5532 better than ua741, I see and hear the difference, now why?

2. What should I be testing and/or what data should I be collecting to better understand and characterized?

Thank you for your time and consideration. I am 100% self-taught savage from the wilderness and stumbled into your camp, but we are not so different, I promise, just had to walk down different road in life. Thanks again.

Hobbyist/DIY guy in a garage. I use Linux. I have briefly tested Eagle and a couple circuit design apps but didn't like anything about any of them, did not spend sufficient time with them either, though. Eagle is going away? Any recommended apps for designing pcb and/or services? I am also open to more artisinal methods. What direction should I point my momentum? Not afraid to try things out but also not wanting to waste time. I have been breadboarding for a minute, learned to solder, benn making some pcb gadgets and think I am ready. Thank you. (Pic is audio mixer with two NE5532 and LM386)

1. System76 Meerkat is my workstation with pop-os, I have 2. a Beelink s13 that I have installed and configured fedora server headless with podman for a development lab, and for 3. My vision was a NAS Samba plus Jellyfin and Homeassistant device. NAS supports 2 ssd plugged directly into usb which host backup for Meerkat and s13.

For 3., I have tried unsuccessfully with a raspberry pi 5, not saying I have any skill whatsoever but I spent a significant amount of time and got so fucking close but it was not a sustainable system that I created in the end I moved on next to a GMK G3 plus which, out of the box, and immediately could not sustain connection to the ssd via usb, I methodically tested all the usb ports with both ssd devices and concluded that there was no fucking way this unit will sustain a connection to these usb ssd for any amount of time. So I am not using that device.

I have ordered and waiting to receive Beelink s12 and going to try that next for my 3. vision.

All that said, I am in the struggle and if anyone had kind words or advice, yes please.

Also, please shoot me straight: am I retarded? Is this a recipe for failure? Is it unreasonable to run those services on s12? Is it foolish to think I can sustain two ssd via usb and backup via Samba with s12?

S13 and s12 are ethernet connected to router, Meerkat is wireless connected.

I genuinely appreciate any attention here, thank you for your time.

*Also wanted to add, earlier I got one of the refurbished servers, Lenovo I believe, off Amazon. It was advertised with 1 TB ssd. When it arrived, there was no ssd and the ribbon cable appeared damaged. Just adding that for the record here as well.