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Old 30th Sep 2018, 10:54 am   #25
David G4EBT
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Join Date: Feb 2003
Location: Cottingham, East Yorkshire, UK.
Posts: 5,766
Default Re: FM to AM converter - variation on a theme!

Quote:
Originally Posted by ms660 View Post
Might be worth de-coupling for RF as well as per the original article schematic (Guy Fernando)
Thanks for your advice Lawrence.

I've amended the layout to reinstate what was 'C1' on the original Guy Fernando converter - 100nF, and have repositioned the 100µF cap on the layout so that it conforms to the circuit. I've renamed the 100µF cap 'C8'. I also stated in my earlier post that the PCB masks were flipped, but in fact they weren't. In any event, I've updated the masks to incorporate the addition of C1 and repositioning of the tracks.

Pic 1 is the updated circuit reinstating what was 'C1' on Guy's circuit.
Pic 2 is the updated component overlay.
Pic 3 is the updated PCB artwork, which is also now correctly 'flipped'.

I'm intending to mount the PCB on spacers using the same mounting screws and positions as does the FM module, and I won't know the actual dimensions for sure until the module arrives, (from a UK supplier) Hence, (assuming that there aren't still any errors!) though the track layout will stay the same, the actual length of the PCB will depend on the position of the mounting holes. The holes shown on th board are therefore just an indication - they're not accurately positioned.

Hope that's of interest.
Attached Thumbnails
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Name:	FM AM Converter MK2 Circuit with FM & MP3 Module.jpg
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Name:	FM AM Converter with Add on FM Modue_edited-3.jpg
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Name:	FM Converter Digital Module version PCB Masks neg and pos_edited-1.jpg
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ID:	170089  
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