Hi There are a variety of VCXO's and TCVCXO's on the Mouser site. Prices seem to range from $3 to $10 for the reasonable candidates.
http://www.mouser.com/ProductDetail/Fox/FOX924B-10000/?qs=sGAEpiMZZMsBj6bBr9Q9afDupvxlfd2QBmF8W0236Ww%3d Is one of the many. It runs at 10 MHz, CMOS output, and actually *is* in stock. Price is $6.41 for a single piece. I'm sure that a bit more digging could get that down a bit. The auction sites also have similar parts. Bob On Mar 28, 2013, at 9:01 PM, paul swed <paulsw...@gmail.com> wrote: > OK it has been a while and I have promised to share results. In the next > few days I will put whats on paper into a schematic and share. I won't > dwell on all of the stuff from October to now. But several front end rcvrs, > and several analog Costas loops were built using MC1496s and another using > AD633 multipliers. Various other glue. > Nothing to rave about. > > What I will detail is what I have done with quite common parts. But what it > isn't is a kit or absolute or anything else. It can be made better. Don't > doubt that for a second. > So what I do have are 4 pretty simple and reasonable parts of the solution. > It really does work even on the east coast. Though MSF can really cause > issues ocasionally. One key part the costas loop is a design I stumbled > across from 1971 designers casebook electronics magazine ca herbst. Was > cleaning out old papers. The article left a lot of detail out. But the > principle is solid. It was surprising at how well it worked the first time. > So what I will share with the Time-nuts are the following schematics. > > A 60 KHz TRF receiver. Takes a 1uv signal and increases it to 2-4 V PP with > AGC and soft limiter. It includes a 60 Khz xtal filter to set the passband > and a tuned stage or 2. There are quite a few possibilities on the > internet. Tried a few. This is my version. But others would work just as > well. > > Digital costas loop using nothing more the a 74hc86 quad exclusive or. > Resistors and caps to integrate. > > The 12 Mhz VCO. Why 12? Thats the crystals I have. Boy can this area use > some help. > > The divider. Cmos 12 Mhz to 0 and 90 degrees at 60 Khz. This is straight > out of any digital application manual. No magic at all. > > When combined this creates a complete WWVB costas loop solution that > delivers a 60 Khz output locked to wwvb without the phase modulation. A > byproduct is the digital data from the new signal. Not used. Not even to > drive a led. > > A path could be added that literally inverts or not the original AM signal > so that spectracom 8170s and Truetime DC60s would work and recover time > correctly. That is a piece O cake. > > So I will get this into a schematic to share over the next day or two. > By the way on performance the system handles sun rise and sets and keeps > ticking. Using a fluke 207 driven by a Rb ref to watch for failures. This > is recorded on a 4 channel chart recorder program on a laptop. I have used > the system to drive 2 X HP VLF 117s and they track as w > Lots of areas that might be improved AGC control and time constants. Adding > a opamp to the 0 degree phase VCO control voltage and also adjusting Time > constants. Though the 12 Mhz oscillator is really standard parts just could > not find something reasonable and off the shelf. Digikey or Mouser stuff. > something with 4 pins and a few $. By the way the control voltage is > .5V/.1Hz. > > Regards > Paul > WB8TSL > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
