Hi Lady Heather is a very Trimble specific program. It's not going to by a lot of help with a non-trimble based design.
LH (as I've mentioned before) really does not calculate a proper ADEV. Not because it's broke, but because it can't without a very stable "third oscillator" to compare to. Bob On Oct 12, 2013, at 3:22 PM, Don Lewis <[email protected]> wrote: > > I just completed my second scratch GPSDO and would like to share a few of > its details and ask a question or two at the end) > > > > I think the point of the below is that it did not cost very much, either > time or money. It was very easily designed and built. I think the > GPS-locked 10MHz output frequency is pretty good .but need to better > understand how to use (Lady Heather?) to calculate ADEVs. > > > > > > I started with a couple of HP part-donor units that came my way from eBay. > (TRULY part units -like they were missing entire pwbs and cables and such > ...no way to easily rebuild ...but that is another story...) > > > > 1. I first built up my own discrete power supplies, needing +5VDC; > +16VAC, and -18VDC using transformer wall warts (no switchers). I used the > some of the large blue filter caps from the donor HP units to help DC > filtering. > > 2. I took an older HP10811 oscillator and its controller-board from a > donor unit and fed the 10MHz output to an oscillator card I had from a donor > 3585A spec analyzer (A21). > > 3. I wrapped the 10811 oscillator in several layers of cork I had around > the house; and attached a small digital thermometer sensor to the outside of > the oscillator, prior to wrapping. It seems to maintain a constant 100F > with little effort or regard to room temperature. > > 4. The standalone 3585A, A21 board takes the 10MHz from the 10811 > oscillator and locks it to its own, discrete, on-board 90MHz oscillator on > the A21 board. Then it nicely divides this 90MHz down several times > (frequencies the 3585A spec analyzer originally needed). > > 5. I get outputs from the A21 board: 90MHz, 10MHz, and100KHz. (lots of > ECL on this little A21 board) > > 6. I then added my own simple divide by 10 to take the 100 KHz to 10 KHz. > > 7. I used an (eBay) NAVMAN-Motorola GPS unit that has a 10 KHz output to > feed an XO; this XO feeds a few RC discretes that develop the analog EFC > back to the HP10811 oscillator. (Adjusting the 10811 oscillator to such an > initial frequency that allows the lock EFC voltage to be positive is > necessary. > > 8. Letting all this run overnight is showing the HP1011, 10MHz oscillator > locked to GPS that has a TI of 100ns with all zeros to the right of the > decimal point, . out to decimal places eight & nine on my good 5370B TIC, > .(decimal places eight and nine fluctuating around +- 20) > > > > Btw .I use my first GPSDO (similar, with NAVMAN/Motorola, but no fancy A21 > board .etc) .as the 10 MHz external reference to the 5370B TIC. > > > > Question, please, how do I get this GPSDO (input) into Lady Heather? I do > have an RS232 interface into my computer for the NAVMAN, and can monitor the > GPS with a simple GPS monitor program.but this is not the locked, > disciplined frequency from the 10MHz HP10811. > > > > With my setup .how does one compute the ADEVs? > > > > -Don Lewis > > Austin, TX (Hyde Park) > > > > > > > > > > > > _______________________________________________ > 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.
