[time-nuts] Re: Time-nuts at WSTS conference
On Thu, 12 May 2022 12:01:48 -0600, you wrote: >I've found that corridor discussions have included redefinition of >SI-second, quantum computers, optical clocks, security on PTP clocks, >time-scale algorithms, uncertainty of different measures. Oh, and I just >won a bottle of scotsh whiskey. Excellent, Magnus! I remember a tech seminar years ago, where the instructor avowed that 80% of the education took place during the coffee breaks! -- Gary Woods O- K2AHC -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe send an email to time-nuts-le...@lists.febo.com
Re: [time-nuts] x86 CPU Timekeeping and clock generation
On Wed, 6 Jan 2021 12:06:35 -0800, you wrote: >14.31818 MHz is 4x the NTSC colorburst frequency (~3.58 MHz). It is also >3x the original PC CPU clock frequency (~4.77 MHz). And many years ago, when Never Twice the Same Color was new, a radio ham in Manhatten wass working 80-meter CW* running a kilowatt nor far from a poorly-shielded video encoder and caused coast-to-coast TVI! Fortunately there were enough Techs who could read his callsign in the interference... *3580? -- Gary Woods O- K2AHC Public keys at home.earthlink.net/~garygarlic, or get 0x1D64A93D via keyserver fingerprint = E2 6F 50 93 7B C7 F3 CA 1F 8B 3C C0 B0 28 68 -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] HP-5372A and HP-5372A operation with no CRT display.
On Mon, 6 Jul 2020 10:42:48 -0400, you wrote: >Certainly not as exciting as bring Cesium Beam standards back to life, but I >do like to keep the old boat anchors glowing, even if they only have a single >vacuum tube. HI . As the instructor at an RCA seminar said, "I like those glass NPN devices with the light inside so you can tell they're on." -- Gary Woods O- K2AHC Public keys at home.earthlink.net/~garygarlic, or get 0x1D64A93D via keyserver fingerprint = E2 6F 50 93 7B C7 F3 CA 1F 8B 3C C0 B0 28 68 -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] low power divide by 5
On Thu, 2 Jul 2020 19:23:03 +0200, you wrote: >Makes me think one could use the input signal edge to synchronize a 2N6027 >based programmable unijunction oscillator, thus effecting a divide by 5. >Unlikely the 6027 would be fast enough for 50 MHz, but maybe a 2 transistor >equivalent using RF transistors? Output would be nowhere near the 40%-60% >range, though. Might just have to build one for fun. And _that_ makes me think of an early Navy airborne Loran set that used step counters to make the time base. Adjustments were through holes in the side of the case, because some poor soul would have to tweak them now and again. -- Gary Woods O- K2AHC Public keys at home.earthlink.net/~garygarlic, or get 0x1D64A93D via keyserver fingerprint = E2 6F 50 93 7B C7 F3 CA 1F 8B 3C C0 B0 28 68 -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Alfred Loomis - an early time nut
On Wed, 13 May 2020 09:23:45 -0600, you wrote: >Given all his accomplishments, he must have been a >"Renaissance Time_Nut"! My favorite quote from a bio of Loomis; he was shown the super secret British magnetron, and an engineer was trying to explain how it made high-power microwaves. Loomis listened and said, "Oh, it's a whistle!" (I dealt with it's megawatt descendent in the APS-20 radar). -- Gary Woods O- K2AHC Public keys at home.earthlink.net/~garygarlic, or get 0x1D64A93D via keyserver fingerprint = E2 6F 50 93 7B C7 F3 CA 1F 8B 3C C0 B0 28 68 -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Help with BG7TBL 2015-07-08 GPSDO>Fixed!
On Sun, 9 Feb 2020 18:10:36 -0600, you wrote: >I'm just curious - what piece of kit >is the MAX3232 installed in? I'm trying to figure out is it is the DCE or >the DTE end. It's a Chinese BG7TBL GPSDO, using UBlox gps module and oscilloquartz OCXO. DCE, with 9-pin serial connector and no handshake. Now talks to either the UBlox monitor program or Lady Heather. Internal stuff like DAC correction voltage not accessible but as I said, plenty good enough for what I need. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Help with BG7TBL 2015-07-08 GPSDO>Fixed!
Once I found the datasheet for the RS-232 interface, I found the TX data was checking in but not out, and the circuitry that makes -V in the MAX3232 wasn't working. Replaced it * and all is well; Lady Heather is giving me nice maps of satellites passing by, and 2nsec excursions on a graph. So now my ancient Davis counter has a really really good timebase and I can tweak my ham rig to within a fraction of a cycle of right. Hardly a "time nuts" level of accuracy, but good enough! Thanks, all! *Lengthy digresssion involving my Navy vocabulary omitted. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Help with BG7TBL 2015-07-08 GPSDO
On Sat, 01 Feb 2020 15:53:45 -0700, you wrote: >Are they both "real" RS-232, both 5v ttl rs232, or hopelessly mixed? Computer port and GPSDO both "real" RS-232. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Help with BG7TBL 2015-07-08 GPSDO
On Sat, 1 Feb 2020 12:24:24 -0600, you wrote: >Hmmm. I do not have any of that equipment, but I do know the RS232 >interface pretty well. It may be that you need to cross over the >connections with RX and TX. Do you have a null modem type device handy? The GPSDO says it only needs send and receive data; no handshake. I've got a break-out adapter in the line passing only those and ground. Reversing t/r doesn't help. Gonna scope the interface chip's ins/outs, but right now the cellar hamshack/shop/man cave is just too (*^&*%* cold! ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
[time-nuts] Help with BG7TBL 2015-07-08 GPSDO
I can't seem to get Lady Heather to talk to it, though I don't get the "no radio" message when the DB9 cable is plugged into the unit. Contains: Ublox LEA-ST-0-002 receiver Oscilloquartz OCXO 8863-XS oscillator The RS-232 interface is a MAX3232 chip. I can see data sent when LH starts up on an RS-232 tester in the line; next step perhaps to scope transmit data in/out on the MAX3232. Does this box send anything on power up? Any known "gotchas" with it? Antenna seems good; no warning LED when it's connected, and after warmup Sys Lock LED is on solid. I'm mostly using the 10mHz output to clock an ancient kit-built Davis counter for Ham radio stuff, so not anywhere near the levels of time-nuttery I see here. TIA, ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Spark timer.
On Fri, 22 Nov 2019 12:54:32 -0500, you wrote: >I picked up a CENCO Oscillating Spark Timer at the MIT flea market. >I would have liked to get an old tuning fork frequency standard but >this old mechanical oscillator peaked my interest and at $5 I could >not resist taking it home. I remember using one of these to time "frictionless" pucks colliding on a sheet of waxed paper in freshman physics lab in beautiful Troy, NY. I thought at the time "hey, an electric Vibroplex!" It pulsed a Model T spark coil, IIRC. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] VHF-UHF Frequency Calibrator
On Fri, 4 Jan 2019 14:49:39 -0800, you wrote: >The 12AT7 dual triode tube used as the oscillator has the crystal connected >between the two cathodes, a configuration I >haven't seen before. Sounds like a Butler oscillator; very popular with Navy avionics back in the day of those glass NPN devices with the light inside. --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] MEMS oscillators
On Thu, 1 Nov 2018 08:54:27 +1100, you wrote: >"An Eidophor was a television projector used to create theater-sized >images. The name Eidophor is derived from the Greek word-roots eido >and phor meaning 'image' and 'bearer' (carrier). Its basic technology >was the use of electrostatic charges to deform an oil surface." GE had a projector that wrote diffraction patterns on an oil film with an electron beam and could do color! The projection tube had a palladium diaphragm that let hydrogen from the breakdown of the oil diffuse out. I was trained on its care and feeding, but never went on one of the few conferences they booked. Any LCD projector can, of course outperform that refrigerator-sized box by a LOT. --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
[time-nuts] OT: problems with Scientific American customer "service"
Anybody else have problems with these folks? Replies direct to me at garygar...@earthlink.net I figured this would be a likely place to ask. -- Gary Woods O- K2AHC Public keys at home.earthlink.net/~garygarlic, or get 0x1D64A93D via keyserver fingerprint = E2 6F 50 93 7B C7 F3 CA 1F 8B 3C C0 B0 28 68 --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
