Andrew,
I was just testing my amp boards discrete one no issue. The Balanced board C1 polarity is labeled wrong, and on my unbalanced output my 1K sine wave is clipped on the bottom no matter what level. It is same for left and right channel, any suggestions ?
Thanks
Bill
I was just testing my amp boards discrete one no issue. The Balanced board C1 polarity is labeled wrong, and on my unbalanced output my 1K sine wave is clipped on the bottom no matter what level. It is same for left and right channel, any suggestions ?
Thanks
Bill
Bill, let me look a bit later today for you. I’m about to go out for a few hours. Can you check the supply voltage right aft he opamp pins (4 and 8 on the 1642 and 4 and 7 on the 1641).
Bill,
can you check the load on your unbalanced outputs? The balanced outputs are derived from the unbalanced outputs, so if you are seeing a serious clip issue on the unbal output, it must also be present on the bal outputs. Check that D5 and D4 are the right way around. Check that C1 has not gone short - did you replace it or just turn it around? If it was reverse biased, it probably went short. I'll look at the PCB when I get back later today.
can you check the load on your unbalanced outputs? The balanced outputs are derived from the unbalanced outputs, so if you are seeing a serious clip issue on the unbal output, it must also be present on the bal outputs. Check that D5 and D4 are the right way around. Check that C1 has not gone short - did you replace it or just turn it around? If it was reverse biased, it probably went short. I'll look at the PCB when I get back later today.
D4 and D5 are 1N44007 devices across the supply to ensure that if its reversed, the board is protyected.
Hi @Bonsai et al.,
Each time I do a diy project, I try to redo PCBs in KiCad as part of my learning experience and also to double check BOMs and things like that. Until now, I learnt a lot from the X-Altra ones. For example, I would never have thought to use SMD pads as through holes ones to link the two layers. One more time thank you for that!
I hope you don't mind if I I ask a few questions concerning the layouts?
In the RIAA board:
- the GND link between R27,R36,37,38 is done using a copper zone, is there any difference in drawing this zone as you did versus a big square?
The way you did it (at least the way I mimic the way you dit it😉:
Versus this alternative?
- Still in the RIAA board, what is the purpose of the big copper zone connecting two of the mounting hole but which does not seem to be connected to anything else (at least as far as I can see and as far I could test)?
- In the PSU board, there is a copper zone to take care of the -18V connections from flash pads to C8,C11 but you seem to use a separate track to reach R26, why not linking from C11 to R26 or using only one big copper zone to connect them all? Is it something related to "separating" "functional/logical" parts of the circuit (sorry if unclear) to prevent "noise pollution" or something?
Thanks, and feel free not to answer if it's not the right place or you don't have time or whatever your reasons are, I definitely won't take it bad.
Raph
Each time I do a diy project, I try to redo PCBs in KiCad as part of my learning experience and also to double check BOMs and things like that. Until now, I learnt a lot from the X-Altra ones. For example, I would never have thought to use SMD pads as through holes ones to link the two layers. One more time thank you for that!
I hope you don't mind if I I ask a few questions concerning the layouts?
In the RIAA board:
- the GND link between R27,R36,37,38 is done using a copper zone, is there any difference in drawing this zone as you did versus a big square?
The way you did it (at least the way I mimic the way you dit it😉:
Versus this alternative?
- Still in the RIAA board, what is the purpose of the big copper zone connecting two of the mounting hole but which does not seem to be connected to anything else (at least as far as I can see and as far I could test)?
- In the PSU board, there is a copper zone to take care of the -18V connections from flash pads to C8,C11 but you seem to use a separate track to reach R26, why not linking from C11 to R26 or using only one big copper zone to connect them all? Is it something related to "separating" "functional/logical" parts of the circuit (sorry if unclear) to prevent "noise pollution" or something?
Thanks, and feel free not to answer if it's not the right place or you don't have time or whatever your reasons are, I definitely won't take it bad.
Raph
Hi Raph,
laying a PCB out, once you follow the basic rules, becomes very much a matter of personal taste.
1. Ground link between resistors - either way will work ok although the first one you show will probably be easier to solder because the thermal mass of the square is a bit smaller.
2. If I have spare space around the board as in the second question, I often fill this with copper because when the boards are made, there is less copper to etch off. I ground it most times, but its not really necessary. I the example you showed, the spare area was over and around the mounting holes so I just grounded it. Note that grounded area is NOT connected to anywhere on the PCB 0V other than through the single ground connection to the chassis via the mounting screws and the standoffs. I could just as well be left floating.
3. In the 3rd example, I didn't want the potentially noisy digital ground to interfere with the +-18V analog PSU ground currents - so it's a star ground connection in effect on the PCB. Same for the +12V relay supply. The digital supply currents are very low, so it is unlikely to have caused a problem in practice.
laying a PCB out, once you follow the basic rules, becomes very much a matter of personal taste.
1. Ground link between resistors - either way will work ok although the first one you show will probably be easier to solder because the thermal mass of the square is a bit smaller.
2. If I have spare space around the board as in the second question, I often fill this with copper because when the boards are made, there is less copper to etch off. I ground it most times, but its not really necessary. I the example you showed, the spare area was over and around the mounting holes so I just grounded it. Note that grounded area is NOT connected to anywhere on the PCB 0V other than through the single ground connection to the chassis via the mounting screws and the standoffs. I could just as well be left floating.
3. In the 3rd example, I didn't want the potentially noisy digital ground to interfere with the +-18V analog PSU ground currents - so it's a star ground connection in effect on the PCB. Same for the +12V relay supply. The digital supply currents are very low, so it is unlikely to have caused a problem in practice.
I'm just busy writing up the module inter-wiring. As per usual this will be pictorial and on slides. 🙂
It will take a few more days - hopefully I can get it down by Wednesday/Thursday
It will take a few more days - hopefully I can get it down by Wednesday/Thursday
I have updated the presentation with the wiring up and final assembly here
https://hifisonix.com/wordpress/wp-...reamplifier-Main-Presentation-Nov-17-2022.pdf
The added slides are pages 56 to 75.
As always, any issues, please let me know.
https://hifisonix.com/wordpress/wp-...reamplifier-Main-Presentation-Nov-17-2022.pdf
The added slides are pages 56 to 75.
As always, any issues, please let me know.
I ordered the parts for the remote control board. the semiconductors I ordered from RS I was not able to buy in single units, I would be willing to mail the ones I don’t need for my build to other builders after I receive them.
Bill
Bill
For the remote board they are all on order. The rest of my boards are built, I won’t have a phono board in mine, and at some point I will build another power supply board.
Bill
Bill
So I received my case from mod shop and I really should have taken some pictures of the unpacking. This is the second case I have purchased from them, Not only do they provide a quality product a cut above, the care and actual engineering of the packing is very impressive. I like to say thank you to Gianluca for offering the diyaudio community his services.
Bill
Bill
Thank you Bill, it's always good to hear this kind of feedback from our customers 🙂 Much appreciated!
@Bonsai
Do you mind sharing the FPE file for the drilling baseplate on your webpage? That way we can use the dimensions for those of us that want to use just your linestage boards (and other sub boards) in our personal diy creations since the pcb's are available for purchase separately.
Thanks,
Anand.
Do you mind sharing the FPE file for the drilling baseplate on your webpage? That way we can use the dimensions for those of us that want to use just your linestage boards (and other sub boards) in our personal diy creations since the pcb's are available for purchase separately.
Thanks,
Anand.
Anand, the base plate drilling has already been up on the webpage as a PDF file for a month or two. Do you want the hole dimensions for the modules separately?
🙂
🙂
Anand, the base plate drilling has already been up on the webpage as a PDF file for a month or two. Do you want the hole dimensions for the modules separately?
🙂
Exactly! I want to see if the hole spacings and dimensions of some of the modules can fit within one of my existing diy designs. If you want you can mark up the PDF file or just upload your FPE file to share, whatever is easiest.
Thanks,
Anand.
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