Help, trying to build Amiga Open Source Sampler

[amifan]

So I decided to try the route of building the Open Source Sampler, I got as far as having the boards built, got 4 spare if anyone is interested in one got the two main chips but figuring out the rest has been a bit frustrating. Each time I look for the other parts in the list they look quite different to the parts used in other builds of the sampler.

1x Maxim ADC0820CCN+ *Got it
1x Microchip MCP6002-I/P *Got it
1x DB25 plug connector
2x RCA receptacles
1x 330ohm resistor
5x 1kohm resistors
1x 10kohm exponential potentimeter
1x 47uf capacitor
2x 10uf capacitors
2x 0.1uf capacitors

I had a look on eBay and they seem cheaper than Aliexpress but the parts never seem to be exactly what I need.

[Jope]

Instead of buying the absolute cheapest parts from around the world, could I suggest going to tme.eu, mouser, farnell or some other electronics wholesaler where you could pick everything into one shopping cart in one go?

Everything you listed as not yet having is a commodity part that everyone should stock.

[levo-ace]

Some details would be nice . A link to the website or pictures of what you have to go by would help .

[amifan]

@Jope, thanks I will check out them out.
@levo-ace, here is the link to the GitHub page: https://github.com/echolevel/open-amiga-sampler

[pandy71]

Buy RPi Pico and use it as very good sampler - you can also have proper DSP in same module. Really don't get why people not taking common uC with embedded ADC - probably cheaper than dumb ADC and as a bonus everything can be properly buffered and processed.

[fxgogo]

That sounds interesting pandy71. Is there a project out there using the Pico?

[pandy71]

Originally Posted by fxgogo

That sounds interesting pandy71. Is there a project out there using the Pico?

Not aware of any ready to use Amiga dedicated sampler projects but there is plenty similar projects for audio processing with help of the embedded ADC (not the best one but better than mentioned 8 bit ADC0820), smart Amiga sampler - i bet even Arduino based cheap ADC will be in overall better due relaxed analog requirements.
Some jitter from Amiga software sampling can be removed if FIFO implemented on uC software... Many possibilities for way lower price (Mouser ADC0820CCN cost over 11E).

[levo-ace]

Are you going to do the SMD or the through hole version .

[amifan]

I am doing the through hole version, I don't`t have the dexterity for doing a SMD version.

[Stedy]

Originally Posted by amifan

I am doing the through hole version, I don't`t have the dexterity for doing a SMD version.

Do you have a few 'hobby electronics' suppliers in your region?

I just searched for a DB25 connector on Mouse and they have 179 parts in stock! Normally I would just purchase a 25 way plug with solder cups, specifying this with Mouser/Digikey takes a bit more work.

A few other hints for components:
1) The 47uF electrolytic capacitors should be 10-16V rated, to fit the PCB footprint.
2) The 10K potentiometer should be a logarithmic scale for audio . A regular 20 or 24mm size part should fit. It will be marked as 'Single Log B' or similar. An 'A' marked part is linear, 'B' is logarithmic.
3) The resistors are all standard 1/4 carbon or Metal film. You may see them as 0207 size in some places.
4) The 0.1uF capacitors could be Y5V (eww) or X7R (nice) dielectric, typically rated 25V to 50V ceramic.

Hope this helps a bit without being too specific.

[amifan]

Thank you this is very helpful, I was at a bit of a loss to which specific parts were needed. I am thinking of maybe going to an electronics shop in Tokyo and bring the list, it might be a bit easier than ordering everything online.

[berke]

Originally Posted by amifan

Thank you this is very helpful, I was at a bit of a loss to which specific parts were needed. I am thinking of maybe going to an electronics shop in Tokyo and bring the list, it might be a bit easier than ordering everything online.

They still have electronics shops in Tokyo? Good old times.


I remember seeing a locally-made parallel port sound sampler at the computer shop when I was just a kid with an A500. This was in Turkey in the late 80's. I noticed (or maybe someone else pointed out) that they had sanded the top of the IC's so that people couldn't read the parts number, go to the "electronics neighbourhood", which was full of little shops selling components, buy the parts and clone their precious two-IC design.


I guess it was a similar design to yours?



Later my mom bought me a GVP sampler, one that came in a transparent acrylic case. IIRC it had pretty a good analog front-end with adjustable filters or gains. I made a phone interface and then an ARexx-controlled voice mail box with DTMF decoding that I would call from the school payphone.



Anyway, saw your Github files, good work!