2nd Chance PI

[württemberger]

Hi Dan,

thanks for your great Projekt.
I have a question about the "Switchboard" (Switch 5). Which Pin´s are connected, if the Button is pressed ?

[dantech]

This is in fact common project with AndyF. He was developing project a few years ago. Above v121 (and at the 2nd ChancePI) is developed by me
But we have to keep in mind that AndyF did huge work



"Straight from a head"

S1 - left/signal mask -
S2 - right/signal mask +
S3 - up/volume -
S4 - down/volume+
S5 - OK/filter reset
S6 - Menu/escape

Personally I use keyboard PCB layout (keyboard_pcb.lay6 file)

http://chomikuj.pl/dantech/2nd+Chanc...579348996.lay6

That PCB is fully verified with schematic (keyboard_schematic.jpg)

http://chomikuj.pl/dantech/2nd+Chanc...5579303636.jpg

You have to compare both ones

[württemberger]

Thanks !

[ripsdevala]

Is there any subtitute for irf9640, the last part.

[kt315]

Is there any subtitute for irf9640, the last part.

substitute is in my BOM file for Barracuda. look it in bara thread.

[ripsdevala]

Yes, i see 9640 have a better result than the others, i will try this 9640 to cuda also.

[ripsdevala]

All parts complete, let me know if there any mistake, im not sure about wrong choke placement from post behind.

Any voltage measurement?
What is the value of C9?
Programing directly from B1 B2 and B3?

[dantech]

B1,B2,B3 comes from "buttons". This is keyboard connector.
You have to programm in the external socket or solder additional wires under the PCB

C9/C18 is the pair of 100n / 100uF in the positive power rail of NE5534. I do not remember which one is C9.

At the beginning you have to run the circuit without atmega, MCP3201, LT1054 and NE5534.
Then you have to check power consumption (several miliAmps), +5V, +12V, -12V, Uref =4,6.
Next you can place ICs in the sockets. Should start at once

By the way you cabn use ADS7816 instead of MCP3201 also.

[ripsdevala]

This c9

according to the scheme, c9 should not exist, on the pcb layout its connect to pin5 LT1054.

[dantech]

Right, I was looking onto another schematic version

[ripsdevala]

Coil industance, resistance?
Or just following the pic, 24 (12+12) top bottom, and outer 18 (9+9) top bottom. I have 0.6mm wire

[dantech]

Follow the picture. I prefer 0,8 mm wire. Then we have 1 ohm and 350uH

I think that 0,6 mm can be also used but resistance will be higher eg. 1,7 ohm, inductance should be circa 380uH. So the coil can be little bit slower (2-3 us)

[dantech]

Any problem, any progress?

[CDI]

Hi dantech, did u ever tried bigger coil than this in your description? If so, which result u got? I'm not interested for small gold, so i can use bigger coil.

[dantech]

I did not try bigger coil but in theory it should work well.
Every process parameter can be customized in the menu in the very wide range so I do not see technical problems to use "frame coil". Of course you have to wind it by thick wire. to keep low resistance as possible and to keep inductance 300-400uH. The coil should be simply fast because pulse width is 120us and the coil should be able to saturate in this time
I saw the poeple has made frame coils for classic ChancePI