first BFOs

[Piotr]

Can anyone direct me to the info about earliest BFOs?

Article, patent number, whatever. Even word of mouth.

According to the Roberts' article it was Daniel Chilson who first patented BFO (Chilson bridge?). Maybe someone know the relevant patent number?

Or maybe someone know Roy Roberts' email?

Thanks,

Piotr

[Carl]

Re: first BFOs

I don't have many of the earliest patents, and have no idea when the BFO was first developed. Roy might know, but I don't think he has direct email -- I used to write him via snail mail. However, he is a member of CAMDTH, and they have a web site, link below.

- Carl



CAMDTH