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I've started to work in this way. If you're interested in my eagle file, I can post them. 4 encoders support. : SID Oscillators, LFO and Filter switches and LEDs : ludo

Hi Thorsten, Yes, don't hesitate to use any pictures you want. ludo

The next would be a mibibox CV and also a mixer based on the PGA... Don't laugh Ixox, just take that as a source of inspiration. Thank you all ! ludo

Now it's time to play ! Thanks to every one who supports my effort and specialy Thorsten for its very nice projects. All the pictures are available on my flickr page, here Am I midibox addicted ? Cheers, ludo

Yesterday night, the box came alive : ludo

Ground is 0V in the DC part of the circuit. I think you will link them. ludo

If you link the ground, you can see that a part of both rectifiers are redundant. This results in a bad rectification that injects a lot of noise. ludo

This design of rectifier is not good at all. The fact is that the half of the bridge is parallelized by joining the both ground. This induces an incorrect signal and generate a lot of buzz. The best design is too put the 7805 after the 7815. But this requires a big voltage drop in the the 7805. Don't forget to mount a heat sink. Ludo

The white mark is not fine with encoder. In Germany, Banzai effect sell those knobs at 2.10 euro. The Boss are sold at 0,60. ludo

You're right, I meant knob. ludo

If you refer to Moog style button, I agree. However I never succeed to find some without a white mark. Morever 20mm diameter maybe too much. ludo

That's a part of the challenge to know if an idea is good or not until the end. I think I will order some black caps... My initial idea was to have something like EMS VCS3. I admit the result is far away to what I expected. But Fisher Price are nice toys. I've ordered this button at a french online component shop, GoTronic. Button are 0,95 euro and caps 0,15. These button are available from 15mm diameter to 45mm. The catalog page is here (only in french). ludo

Hi Folks, I'm beginning the assembly of the front panel. I couldn't resist to post some pics. The complete set is available on my flickr page. Cheers, ludo

Hi all, Today, I've received the front panel from Schaeffer. thefRont, the connector were bought from Radiospares. Ludo

Wow, that's amazing. I've receive a speakjet from HVW Technologies. I intend to use a little AZERTY keyboard and integrate it in a box. Do you thinkk that is something easily achievable in terms of software ? On the hardware side, I know it's not so complex. I aim to write the sentences to be spelled. Cheers, ludo

Some new photos on my flickr set. I've rearrange the inside of the box and mounted the PSU. It's better but not yet complete. And a teaser of the front panel. Cheers, ludo

I'm also designing a board to host 4 PGA2311. I will post the PCB as soon as tested and validated. But I'm facing to the audio routing system (with TL072). If you have some source of schematics... ludo

Hi, I'm also working on a mixer based on 4 PGA2311 and one Core. Do you know if a preamp part is needed is I want to send the same signal to several PGA input ? Regards, ludo

Yep. The voltage oscillated at less than 10 mV. And the sound seems to have not too much buzz. I never have a c64 PSU, so I can't compare. Yes, that's complicated. It's an adjustable regulator LM317 fixed at 4,2V with the pot. It's the best system I found to power up the LCD backlight. It needs 460 mA, that's quite amazing, and a serial resistor of 5 ohms at 3 Watt is not the prefered solution because the pots allow to low the luminosity. ludo

The Doc's hand schematic is the one I used. Thanks Doc ! ludo

Hi, It should. The diodes are on a 2/10" (5,08 mm) grid. You're right. ludo

Attention à ne pas s'en tenir au premier qui est faut. Il faut cascader les 78xx. ludo

After spending a long time on this PSU, I found the cascaded 78xx solution is the best in term of noise. My initial design produced a lot of buzz. Thanks for your help, ludo

There is a dedicated script that allow BMP import. Look at File > Script. ludo

Thanks for your suggestion. However with your design, the 7812 is overload. The 4.2V used for the backlight consume 450mA and main 5V for logic and LED has a similar need. Moreover, I've read somewhere that cascading 78xx may produce a lot of noise. As 7812 provide current for SID module, this not, in my opinion, acceptable. My major concern is about the rectifiers. Two diodes are parallized and I feel that's not a 'clean' design. But it works even if they come hot. As I've said in my previous post, 12VAC if perfect to provide 12VDC. The rectifier drops the voltage to 17V (1,42 x 12, rectified current rules) and the voldate drop down of a 7812 rectifier is about 2V. ludo