Hi I’ve built maybe a dozen of these over the years. I have never used a board for any of them. They all go down on a piece of scrap copper clad and point to point / dead bug wire up. You get a good ground and leaded parts are easier to work with anyway.
Bob > On Mar 24, 2016, at 9:04 AM, jimlux <[email protected]> wrote: > > More like $40 in parts, without a board, etc. > The RPD-1 is $20.70 > LT1678/LT1679 is a nice low noise opamp that does rail to rail and is about $5 > etc > > > > On 3/24/16 4:42 AM, Bob Camp wrote: >> Hi >> >> Pretty simple: >> >> Double balanced mixer, RPD-1 is one option, there are others. >> >> Fairly simple L/C lowpass between the mixer and an op-amp. >> >> 20 db positive (non-inverting) op-amp amplifier string after the mixer >> >> Output of the string goes to the sound card. Use a good (dual / quad) audio >> op amp >> >> Quadrature amp picks off the output of the first op amp stage, switch and >> resistors to set gain, pot to set op point. >> >> ==== >> >> So what you have is an old style quadrature phase noise amp and “PLL”. More >> or less a very junior version >> of the 3048 test box. Like any setup of this sort, you check two similar >> oscillators. They run in quadrature and >> you do a few “measure this with switch in position A” sort of things to set >> things up each time. >> >> Nothing exotic. >> >> Bob >> >>>> >>> >>> Any documentation on this $40 phase noise test set? >>> >>> Rick N6RK >> > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
