UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - FM to AM converter

David G4EBT · 27th Sep 2018, 11:24 am

What a great idea Derek!

As you say, those little units are so cheap - even from a UK supplier, only £7.00 or so with free P&P. I might have a go at one, if only out of interest. Taking into account the component value changes that you made, and modifications to the circuit, I've attached a sketch which I think incorporates all of the changes that you made if I've understood correctly.

Presumably, for convenience, both the modulator section and the FM unit could be powered from an internal PP3 battery rather than a 'wall wart' unless the current consumption of the FM unit is too high to make that realistic?

I notice that the remote control will switch the FM unit itself on an off, but I imagine that the only way to switch both the modulator and FM unit jointly, would be by an on-off switch on the modulator to cut the power supply to both units?

Incidentally, what's the length and height of the FM unit please Derek?

27th Sep 2018, 11:24 am	#6
David G4EBT Dekatron Join Date: Feb 2003 Location: Cottingham, East Yorkshire, UK. Posts: 5,763	Re: FM to AM converter - variation on a theme! What a great idea Derek! As you say, those little units are so cheap - even from a UK supplier, only £7.00 or so with free P&P. I might have a go at one, if only out of interest. Taking into account the component value changes that you made, and modifications to the circuit, I've attached a sketch which I think incorporates all of the changes that you made if I've understood correctly. Presumably, for convenience, both the modulator section and the FM unit could be powered from an internal PP3 battery rather than a 'wall wart' unless the current consumption of the FM unit is too high to make that realistic? I notice that the remote control will switch the FM unit itself on an off, but I imagine that the only way to switch both the modulator and FM unit jointly, would be by an on-off switch on the modulator to cut the power supply to both units? Incidentally, what's the length and height of the FM unit please Derek? Attached Thumbnails __________________ David. BVWS Member. G-QRP Club member 1339. Last edited by David G4EBT; 27th Sep 2018 at 11:40 am.