grahamdocman
pfm Member
I’m about to rebuild / replace my NAC42.5 with: Neils MMB, populated with his NJ 729 and 323 cards, and build his Mini PhonoMB with 323 cards (for my Vinyl collection) – I’ll then run the outputs from this through Neil’s MMB
Apologies in advance: I’m not in any way an electronics expert, I can follow a circuit diagram, pictures and schematics to populate a board, but if asked to identify e.g. "the input or feedback caps", "back or front end "or I wouldn’t know where to begin, so please feel free to make your answers as basic and simple as possible.
Once I’ve completed uptodate BOMs from all the information I’ve been able to pull together on PFM (and from your help) for Neil’s MMB, Mini PhonoMB, 729, 321 and 323 cards, I‘ll post all the BOM details for all the boards in the reference section.
Once I’ve completed my builds (hopefully successfully), I'll post photos and details of my build progress as a separate DIY thread for anyone else to follow.
Before I place my Mouser etc. order I need some help on a few components, otherwise it looks like my project to will be a non-starter.
I’m intending to use a 32V supply for each motherboard
MMB and Phono MB questions I need help with:
1) 2SK117 – seem unobtainable – but I can’t seem to find an equivalent – recommendations please
2) If the raw MMB supply is 32V, will I need a higher wattage rated resistor e.g. 2 or 3w for this position (rather than the 1/4W resistors elsewhere on the board ?
323, 321 and 729 board questions – common to all:
3) The BC550 – the closest I can find are these – with BCU ‘specification’ https://www.mouser.co.uk/ProductDetail/512-BC550CBU
4) The BC560 - unobtainable – I have read that these are the current equivalent BC557C https://www.mouser.co.uk/ProductDetail/637-BC557CBK
Have I got it right or is there a better alternative ?
Please feel free to reference your advice to the question 'numbers' above for clarity.
That’s it, if you can help me resolve the above, I’ll place the orders and I’ll be ready to go ahead.
Thanks in anticipation of your help and patience.
Apologies in advance: I’m not in any way an electronics expert, I can follow a circuit diagram, pictures and schematics to populate a board, but if asked to identify e.g. "the input or feedback caps", "back or front end "or I wouldn’t know where to begin, so please feel free to make your answers as basic and simple as possible.
Once I’ve completed uptodate BOMs from all the information I’ve been able to pull together on PFM (and from your help) for Neil’s MMB, Mini PhonoMB, 729, 321 and 323 cards, I‘ll post all the BOM details for all the boards in the reference section.
Once I’ve completed my builds (hopefully successfully), I'll post photos and details of my build progress as a separate DIY thread for anyone else to follow.
Before I place my Mouser etc. order I need some help on a few components, otherwise it looks like my project to will be a non-starter.
I’m intending to use a 32V supply for each motherboard
MMB and Phono MB questions I need help with:
1) 2SK117 – seem unobtainable – but I can’t seem to find an equivalent – recommendations please
2) If the raw MMB supply is 32V, will I need a higher wattage rated resistor e.g. 2 or 3w for this position (rather than the 1/4W resistors elsewhere on the board ?
323, 321 and 729 board questions – common to all:
3) The BC550 – the closest I can find are these – with BCU ‘specification’ https://www.mouser.co.uk/ProductDetail/512-BC550CBU
4) The BC560 - unobtainable – I have read that these are the current equivalent BC557C https://www.mouser.co.uk/ProductDetail/637-BC557CBK
Have I got it right or is there a better alternative ?
Please feel free to reference your advice to the question 'numbers' above for clarity.
That’s it, if you can help me resolve the above, I’ll place the orders and I’ll be ready to go ahead.
Thanks in anticipation of your help and patience.
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