GGG PT-80 board convert to SHecho??

[El Heisenberg]

Hey...


You can't get a PCB for the SHecho anymore, but you can just get the kit for the PT-80 delay.

But you could easily use the PT-80 board and build a SHecho by wiring the SHecho part on another board. It's only 2 or 4 or 5 connections really. The SHecho would use less components too if you don't count an extra IC. 



http://www.generalguitargadgets.com/diagrams/pt80schem.pdf?phpMyAdmin=78482479fd7e7fc3768044a841b3e85a

http://www.generalguitargadgets.com/pdf/ggg_shecho.pdf






My question, besides "am I missing something and this is gunna be hard?" is, is this even worth doing? SHecho has longer delay time right? But does it sound crappier? I dunno why they only sell PT-80 kits and boards at Generalguitargadgets.com and not SHecho boards.  Unless it really wasn't that great a project??



Should I do it?

[El Heisenberg]

Also, the PT-80 kit from GGG comes with the charge pump set up, so I'd be running the SHecho at 12v! Why not? High current draw but I've got 1000ma at my disposal.



But small bear does not seem to sell the SA571.... Which means I have to buy the PT-80 kit from GGG. And then I can't make a PT-80 with the princeton chip after making the SHecho.


HellOOOo out there!!!

[El Heisenberg]

Eh couldn't wait for advice. Ordered all parts. But no spare SA571.


Anything else I can do with that princeton chip?? That is if this all works out. Which it should..

[anchovie]

Perhaps you need more patience - half the world may well be asleep right now! Small Bear sells the V571D, which is a substitute for the NE571/SA571.

Connecting the pins of the HT8955 to the 41256 RAM is not fun on vero or perf! If you're going to make a board for these, you may as well etch the whole SH-Echo board from the artwork in the PDF.

[El Heisenberg]

Not fun or very hard? I've built huge stuff on perf. I know it ain't fun, but I've never etched a board and I'm really concerned about drilling holes in the PCB so I've never tried. I mean, would you just use a hand drill?? And that's AFTER i've learned how to etch a board. Don't wanna try a big board with tons of traces for a circuit that uses parts I can't get locally and that are expensive when I don't know how to. I'd have to start with like an LPB-1 or something and I don't want an LPB-1.


I've built Boss OC-2 and Mobius Trip looper entirely on Perf. This should be no prob. It's just the two ICs and a very few resisters and capacitors. And then I got a PCB to work with so even easier.




About the SA571, I JUST NOW noticed they sold em, AFTER I'd already placed my order GRAAH! Pateince is right...

[El Heisenberg]

Speakin of patience, I got all hyped up over thisproject. I spent 150 bucks just now. and I wanna build my pedals NOOOOOWWW!!!! Oh WHEN will they invent INSTANS delivery?!

[anchovie]

You'll notice that the pin placement in the schematic bears little resemblence to how the chips actually look. The "fun" part will be connecting them up when they're sitting together on a board! The one I did on perf uses a lot of jumper wires and as a result looks like a miniature old-style telephone switchboard.

[El Heisenberg]

This looks relatively easy to me. The mobius trip and Boss OC-2 were really tough. I can handle a buncha jumpers I think.


But I got to thinkin, why not just have both in the same box??

You could switch the delay portions with a DPDT switch eh??? But that'd be harder to implement on the board...Lemme see.... and the delay time pot is 50k for PT-80 and 500k for SHecho.

[El Heisenberg]

well if anybody cares I got it to work alright and it was really easy. Just a 3PDT switch. I left 2 caps and two resistors off the PCB which gave me plenty of room. I was going to use two stomp switches, and I'm glad I didn't. The only difference that I can tell between the two is the delay time. You gotta struggle to hear how much better the PT-80 delay sounds compared to the SHecho.

Just found the Slackers Echo Base now too. Kickin myself for not building that instead. Though this pedal does sound really nice. I don't regret doing what I did. The SHechos longer delay time is cool. I do wish I'd ordered 5 more PT2399 chips tho...

[El Heisenberg]

I need to learn how to do graphics and stuff. I'm just holding two cans of spray paint at once and hoping it turns out. Then using either white-out pen, sharpies and label makers.