The two IC pinouts are drawn wrong. Pin 2 is inverting input not pin 3.
If it is wired like your schematic, where is the feedback loop on the ICs?
If it is wired like your schematic, where is the feedback loop on the ICs?
Thanks, my fault.
I will change it.No, i only make my own boards. But i will publish gerber files so you can order/make your own pcb's.
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Today i designed the preamp PCB to test the prototype.
You can devide the PCB in two. Between preamp and powersupply.
Tubesockets can be mount on bottom or top side.
Changed schematic with better anode supply for tubes.
Ronny
You can devide the PCB in two. Between preamp and powersupply.
Tubesockets can be mount on bottom or top side.
Changed schematic with better anode supply for tubes.
Ronny
Attachments
Thanks , it is good that i not have ordered 100 PCB's.😉
I connect the heaters in serie to the 12v as in the phonodude design.
I will change the pcb design and schematic.
I connect the heaters in serie to the 12v as in the phonodude design.
I will change the pcb design and schematic.
I like my bendix 2c51 tubes best with 6v dc or 6,5v ac supply. Did some heater supply testing 20 years ago.
Also look how brite they glow on 6v dc.
Also look how brite they glow on 6v dc.
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Today i had time to complete the soundpart. Tested it with my thorens TD160 mk2 modded and a ortofon 2m blue mm cartridge. One thing i noticed direcly, background is death quit. Like a battery operated preamp. Riaa frequency respond is within +/- 0,5db. First soundimpression without impedance tuning, tight, dynamic and big sound stage. Very promising. Hopely i can compleet the comfort part in the next view weeks.
The transformer which is custommade works great.
The transformer which is custommade works great.
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This afternoon while listen to Eva Cassidy and Ray Charles i designed the comfort part. See picture below.
After rolling some opamps and tubes i prefer the AD847 and Bendix 2C51 combination for the sound part.
The phonopreamp is ideal for rolling opamps and tubes.
Next i build the comfort part and program the software for the Arduino Mega.
After rolling some opamps and tubes i prefer the AD847 and Bendix 2C51 combination for the sound part.
The phonopreamp is ideal for rolling opamps and tubes.
Next i build the comfort part and program the software for the Arduino Mega.
Attachments
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Hello Ronny,
when i have completed this build. I publish schematic as build, designspark pcb files for pcb ordering, pcb pdf for diy and source code for arduino mega.
Ronny(Koifarm)
when i have completed this build. I publish schematic as build, designspark pcb files for pcb ordering, pcb pdf for diy and source code for arduino mega.
Ronny(Koifarm)
I have build the comfort PCB. Still listening every day to the sound part. Next i test the comfort PCB just with manual control after that i need to program the arduino software. I have a arduino mega 256 with colourtouchscreen.
The housing i also need to make myself from 25mm mdf. I think i still needs 1 or 2 months to complete this project.
I shall try to publish some photos.
My time for this project is some what limited because I have at the moment 6 other projects with higher priority.
The housing i also need to make myself from 25mm mdf. I think i still needs 1 or 2 months to complete this project.
I shall try to publish some photos.
My time for this project is some what limited because I have at the moment 6 other projects with higher priority.