Zvex SHO

[Nacho5]

Hi! I'm from argentine. I'm building this proyect and i have some questions.



C2, doesn't show where go the positive?
Reading this post http://www.diystompboxes.com/smfforum/index.php?topic=82566.0 says that it's better if put a zener diode, where?

I want to put this proyect in a 1590a enclosure

Thanks!

[Mustachio]

- or ground is on the bottom next to the G . If  you follow it over you see it connects to ground on the board after resistor 4.

Hope that helps

[davent]

On the layout, for C2 you can see it has one square pad and one round pad. The square pad should always represent the +ve connection or pin one on an IC etc...

For the zener, it replaces the two D1&2 and is there to protect the MOSFET. The schematic Rick based the layout on is an early version of the SHO. ZVEX published the schematic for the later version with Zener here. http://www.zvex.com/module_instructions.pdf
It also adds some power supply filtering so it will play nice with both batteries and an external power supply.

The circuit is ideally suited to a 1590A build, small parts count and only one pot.

dave

[LucifersTrip]

C2, doesn't show where go the positive?

it's always cool to check out a schematic for details
http://analogguru.an.ohost.de/193/schematics/Zvex_SHO.gif
http://www.antonine-education.co.uk/Salters/TRA/Sensing_files/image003.gif

[Nacho5]

Last questions. I don't have 5.1k resistor, Can i use 5.6 or 4.7k? Potentiometer are 1-2-3 looking at the image?

Thanks.

[PRR]

> doesn't show where go the positive?

It does.

That layout creator draws capacitors with more-grey on the side with the "-" stripe.

Yes, this is VERY hard to see with the circuit traces underneath.

And as Dave said, in this case the pads are drawn round and square.

> don't have 5.1k resistor, Can i use 5.6 or 4.7k?

Most audio work is + or - 10%, even 20%. (Like if you are hired for a 20 minute set. Play for 18 or 22 minutes, you probaby get paid.) Yes, use the nearest reasonable value.

[LucifersTrip]

Last questions. I don't have 5.1k resistor, Can i use 5.6 or 4.7k? Potentiometer are 1-2-3 looking at the image?

Thanks.

since you already have a 100K...if you're really worried, put the 100K in parallel with the 5.6K = 5.3K

[davent]

Here's a reverse parallel calculator that comes in really handy. Plug in your target resistance and the acceptable percentage of tolerance and it gives you a chart with all acceptable resistor pairs that will give you the results you seek.

http://www.sengpielaudio.com/calculator-parallel.htm

dave