[time-nuts] Anyone heard of a Rubidium Standard called a Varian X-4700A?
Hi all, A number of years ago when I lived in Denver, I knew George Kamas of whom worked in the (then NBS) Time and frequency Labs. He was able to purchase a lot of the equipment that they disposed of and I wound up with one piece that I only had running for a short time. It is a Varian X-4700A serial #4. I was told by George (and I have no way to know I f this was true) , that this unit was modified by NBS from the original Varian dividers and such, and was at one time used as the actual unit to steer the transmitters at WWVB as they has the cesium bank to get the actual frequency and time, but they wanted they best they could get for short term stability to drive the transmitter frequency for comparison purposes. This would have been steered by the bank of cesium clocks and synced to USNO I am sure, but this unit runs on 24VDC, is a monster as far as size, and I am not sure if it still works, but it did at one time when I fired it up. I have pictures if anyone would like to see what I am talking about. I suspect that Varian will have nothing to do with any questions asked, and NIST will have tossed any records regarding such equipment, but has anyone else any info that can shed some light on this beast? Thanks, Jerry ___ 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.
Re: [time-nuts] SDR Radio Opinion- Next Question
Have you ever looked at the unit put out by Ariel Rocholl called the RF Explorer? (link - http://micro.arocholl.com/) I bought one of these units and although they do not have everything ( I would love to have different demods on it), it has been an impressive unit, and inexpensive. I believe as Ariel gets more people interested in the handheld spectrum analyzer concept,he will be building better units with more capabilities. He has the spurs and birdies and other noise makers in any of these type of units, but he knows where they are and have taken them out ( mostly) in firmware. I bought one of the wideband units and even though the standalone units does not look very impressive, the Windows software make it into a very nice inexpensive and quite accurate handheld spectrum analyzer. I am not associated with Ariel, but he is approachable if you wish to talk to him ( I believe he is in Spain). I got mine from China at Seedstudio and other than one minor battery issue that they resolved I am very happy with it. Let me know if there is anything I could let you know if the online data does not tell you enough. Thanks, Jerry Chafee J. Forster j...@quikus.com wrote: OK. Thanks everybody. Can you please reccomend a make/model? I'd like something like: 75 to 1300 MHz USB Ability to function as a crude SA. Not crawling w/ birdies or aliasing issues. Will run on Win XP. Demod selecttable for all modes at all frequencies. In a package, rather than a loose PCB. $150 Prefer: SMA rather than RCA or F Receiver and SW from same vendor. Suggestions, please. Thanks, -John === ___ 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.
