- radio time code clock error - 4 Updates
- Electric meter conversion to wireless, I doubt this could be safe - 5 Updates
- CRT Television Hum - 12 Updates
| Jeff Liebermann <jeffl@cruzio.com>: Jul 07 11:37AM -0700 On Sat, 04 Jul 2015 13:10:22 -0400, Phil Hobbs >the sky. ;) >Cheers >Phil Hobbs Does the NIST use a sundial for a primary time standard? I realize that budget cuts have necessitated economy measures, this seems a bit extreme. >(We just had a leap second.) Yep. That felt good. I got one second of extra sleep. -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
| Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Jul 07 03:08PM -0400 On 07/07/2015 02:37 PM, Jeff Liebermann wrote: >> Second best. They adjust those ones to match that yellow thing up >> in the sky. ;) Cheers Phil Hobbs > Does the NIST use a sundial for a primary time standard? In a way, they do. Civil time is adjusted to match mean solar time. > seems a bit extreme. >> (We just had a leap second.) > Yep. That felt good. I got one second of extra sleep. I was awake, advancing science. ;) Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net |
| N_Cook <diverse@tcp.co.uk>: Jul 08 09:22AM +0100 On 07/07/2015 19:37, Jeff Liebermann wrote: > extreme. >> (We just had a leap second.) > Yep. That felt good. I got one second of extra sleep. The new generation of atomic clocks, accurate to 1 second in 15 billion years,supposedly - how do they know , without a more accurate clock than that to check it against? |
| Jeff Liebermann <jeffl@cruzio.com>: Jul 08 08:38AM -0700 >The new generation of atomic clocks, accurate to 1 second in 15 billion >years,supposedly - how do they know , without a more accurate clock than >that to check it against? Possibly by consensus. Just make reference measurements on as many inaccurate sources as possible, average them together, and by the magic of statistics, the average will be more accurate than any individual measurement. That's because given a sufficiently large supply of erroneous data, the errors tend to be in opposite directions and cancel each other. For example, you could average the noon sight reading from a huge number of sundials or sextants, and the average will give you NIST grade accuracy. If this is a problem for you, just buy one of these: <https://www.kickstarter.com/projects/846511652/the-worlds-first-true-atomic-wristwatch-the-cesium/description> and you won't have to worry about the sundials and sextants that the NIST probably secretly uses for calibration. You'll have a personal time standard that you can trust. Or, just build your own: <http://www.leapsecond.com/pages/atomic-bill/> Once you have an accurate clock, all you need to do is decide which time standard you want to use (LT, GPS, UTC, GMT, GMAT, GAST, SAT, TAI, Loran, MST, UT, TDT, TBT, TGC/TBC, etc. This might help you decide how to set your cesium wrist watch: <http://www.ucolick.org/~sla/leapsecs/timescales.html> Note that some of these are NOT astronomically based, do not include leap seconds, were established for political reasons, and don't agree with other standards. For example, the current differences between UTC, GPS, and TAI at: <http://www.leapsecond.com/java/gpsclock.htm> Also, please note that all of these standards were created and are managed by various committees, and we all know how ineffective a committee can be at getting things right. Perhaps you should just get a wrist sundial: <https://www.google.com/search?q=wrist+sundial&tbm=isch> One can't trust the time gods to get it right: <http://802.11junk.com/jeffl/crud/GPS-vs-UTC.jpg> -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
| Jon Elson <jmelson@wustl.edu>: Jul 07 03:46PM -0500 > modification, to increase the distance squared I've considered moving the > meters to a utility pole which is on my property about 75 feet from the > house. this would probably have to be at my expense I suspect. Do you have a cell phone? It emits enough power to be received 20 miles away, and transmits bursts 20+ times a second when you are talking. The electronic meters send messages to a concentrator that is no more than about 2 blocks away, every few minutes. Generally, the concentrators send the data to a central site directly, through a second antenna on it. There are 50 KW radio stations in almost every town, and TV stations (now all in the UHF band) running 100KW - 500KW output. It seems ridiculous to complain about these meters, when people are using cell phones, bluetooth, and all manner of other devices that radiate far more energy. Jon |
| Chris Jones <lugnut808@spam.yahoo.com>: Jul 08 10:56AM +1000 > need something to jump up and down about my grand children sleep in > the room adjacent to the meters and I think that I understand a > little bit more about this, and it concerns me. You could get a roll of aluminium foil and wallpaper the wall between the meters and the bedroom. https://www.youtube.com/watch?v=urglg3WimHA Depending on how careful you are with the joins you could achieve a very low field strength. This is probably counterproductive as it may attenuate cellphone signals and thereby cause the cellphones that the children are using to ramp up the transmitters to maximum power right on their heads. |
| Jeff Liebermann <jeffl@cruzio.com>: Jul 07 10:07PM -0700 On Wed, 08 Jul 2015 10:56:58 +1000, Chris Jones >You could get a roll of aluminium foil and wallpaper the wall between >the meters and the bedroom. There's a good chance that you may already have the foil in place. Some construction uses foil backed fiberglass insulation. In the roof, there's foil backed foam board and glass wool. >attenuate cellphone signals and thereby cause the cellphones that the >children are using to ramp up the transmitters to maximum power right on >their heads. Nope, that doesn't work. Aluminum foil reflects RF and sends it in some other direction. Put foil in the walls and you could just as easily increase the RF field strength as decrease it. For example, the corners of a room make a nice 90 degree corner reflector antenna. Instead what you need is an RF absorber, not a reflector. Carbon foam is good. A wet towel will also work. Anything that absorbs RF. -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
| "Shaun" <stereobuff07@gmail.com>: Jul 08 12:50AM -0500 wrote in message news:ce3b21ad-0c73-4be7-98f1-22485d8fc6ba@googlegroups.com... We received a notice from the power company that they intend to replace our two electric meters with the new wireless units. These meters emit short bursts of RF multiple times a day at a fairly substantial RF level. These transmissions are received by a "collector" which is apparently mounted on a utility pole on the street. This data is sent to a receiver and computer in a power company truck as it drives by and returned to their office where it's downloaded and bills are generated. Great for the power company but not for the meter readers. There are people all over the country up in arms over these things. Some have blocked installations and have been arrested for it. While it's true that many of them are non technical people who just need something to jump up and down about my grand children sleep in the room adjacent to the meters and I think that I understand a little bit more about this, and it concerns me. I asked the power company to provide me with more information and initially I was stonewalled until I contacted my state representative who then contacted them for me. Now they're kissing my ass with information but still telling me this is going to happen at some near point in the future. Has anyone else had to deal with this and can you comment on my safety concerns? If it's true that there is no recourse to them making this modification, to increase the distance squared I've considered moving the meters to a utility pole which is on my property about 75 feet from the house. this would probably have to be at my expense I suspect. The following is some information about these meters. Some of it I had requested and some extra which they threw in. I know that it's a lot to look at but if you can I'd really appreciate if you guys could please have a look at it and tell me what you think. I'm really concerned about this. Thanks very much. Lenny Q. I understand these units operate in RF - Radio Frequency. Are they emitting short or long range signals? A: The signal from the meter is transmitted in the range 902-928 MHz (mega-hertz). The reading capability is dependent on a number of variables and cannot be accurately assessed without site specific information, but typically the signal may be received by the meter reading equipment within 1/4 mile or so. 2) Q: Regarding the signal, is it a "Bubble-Up" unit where it is transmitting all the time or is it a "Wake-Up" unit where it transmits when it receives a signal? A: The meter transmits reading data every 30 seconds in a brief milliseconds burst. The manufacturer designed it that way to accommodate any reading schedule required by the utility. The meter is a one-way communication device. The meter would not know when the reading device was going to be in close proximity to the meter, therefore it needs to transmit frequently so that it may be read whenever the reading device is nearby. 3) Q: What frequency and wattage of transmit power is the unit operating at and at what antennae gain? Ex. Unit transmits at 900MHz with 1 watt of transmit power with antennae gain of 0. A: The signal from the meter is transmitted in the range 902-928 mhz (mega-hertz) The maximum power output for the endpoint devices is less than half a watt, while the maximum power output of the collection device is less than 1 watt. In comparison, the average light bulb is 60 watts. Frequency = 909 to 922 MHz Transmit Power = 147 mW (21.67dBm) Antenna Gain = 0 dB. 4) Q: What's the antennae gain at peak power and what wattage is the peak power? Ex. Antennae gain of 4.0 dBi for peak level power of 2.5 watts. A: The maximum power output for the endpoint devices is less than half a watt, while the maximum power output of the collection device is less than 1 watt. In comparison, the average light bulb is 60 watts. Frequency = 908 to 923.8 MHz Transmit Power = 250 mW (24dBm) Antenna Gain = 2.2 dB 5) Q: How many times in total - both average and maximum - is the unit scheduled to transmit during a 24-hr time frame? A: The meter transmits reading data every 30 seconds in a brief milliseconds burst - about 53 milliseconds referred to as the "duty cycle". The total RF transmission time in a 24 hour period is between 1.5 - 2.5 minutes depending on the type of meter and therefore data being transmitted. Signal levels are 1/10th of the "Maximum Permissible Exposure Levels" as defined by the FCC--lower than many everyday appliances and electronic devices around your home, and are only transmitted briefly and periodically rather than constantly. What's the "first hop" technology being used to send? Ex. Mobile Radio Frequencies? Mesh Radio Frequencies? Fixed Radio? A: This is not AMI, this is AMR. There isn't any 'first hop', the data is transmitted to a computer in a vehicle driving nearby and then the computer is returned to the utility at the end of the day and directly connected to the utility internal network and the meter readings are uploaded to utility internal systems. 6) Q: Is this unit considered to be a "Licensed" or "Unlicensed" transmitter by the FCC? A: The meters operate in the unlicensed 902-928 MHz frequency range and the devices are regulated by the FCC. Itron's products are stringently evaluated for RF safety and meet all Federal Communication Commission (FCC), Industry Canada (IC), and Institute of Electrical and Electronic Engineers (IEEE) standards. FCC OET Bulletin 65 supplement C Edition 01-01 (known as OET-65C) provides further guidance on determining compliance for portable and mobile devices. 7) Q: Because each unit needs power to run itself, what is the unit's power consumption rate per month? Ex. 2 kW hours? 1kW hours? Also, what would be the additional monthly cost of the power the unit needs to function (based on the # of kW hours it needs to function) as I know you guys just had a rate hike? · A: The power to the meter components is supplied on the line side of the meter. Therefore there is no cost difference associated with the running of the AMR meter to your previous meter. We are enhancing our technology to serve you better. Installing AMR meters allows us to continue to provide safe, timely, accurate meter reading but at a lower cost. Controlling costs is an important factor in determining Eversource rates. 8) Q: Does the unit have a battery? What is the battery's life (in years)? A: Yes there is a battery in the unit. The battery's life is the same as the life of the meter which is 20 to 25 years.. For more information pertaining to the AMR C1SR Meter please visit the ITRON website: https://itron.com/na/resourcesAndSupport/Pages/RF-Resource-Center-FAQs.aspx https://itron.com/na/resourcesAndSupport/Pages/RF-Resource-Center. Going wireless is easy; just open up the meter and cut all the wires out of it. Job Does...... But it won't work anymore and but it is wireless. ;-)) Shaun |
| captainvideo462009@gmail.com: Jul 08 06:33AM -0700 > For more information pertaining to the AMR C1SR Meter please visit the ITRON website: > https://itron.com/na/resourcesAndSupport/Pages/RF-Resource-Center-FAQs.aspx > https://itron.com/na/resourcesAndSupport/Pages/RF-Resource-Center. To answer your question Jon, yes I do use a cell phone, but rarely, my grandchildren are too young to have phones and no you won't find a bluetooth sticking out of my ear. It's also a matter of choice. I choose to use my cell phone and I've chosen not to use wireless or a bluetooth. What the power company is doing is taking away my choice and that's just wrong. Here in New Hampshire we have a motto. If you Google our license plates you'll see it. It reads: "Live free or die". That means something to all of us. I don't mean to get into a political debate here but really when you boil it all down regardless of power level, in a free country what right do these people have to irradiate me against my will? Lenny |
| "Snuffy \"Hub Cap\" McKinney" <Snuffy-Hub-Cap@Livebait-McKinney.com>: Jul 07 12:02PM -0700 I have a analog TV that is still working fine and no plans to replace it. Over time, it has developed an audio hum - I'm guessing it's 60 Hz. When the picture is dark, the hum is nearly gone. The brighter the picture, the louder it is. I'm guessing some kind of filter on the speaker connections would do it, maybe something as simple as connecting a capacitor circuit.... But, as I ain't the sharpest feller with audio electronics, I thought I better ask the genius pool here! First I thought was a power cord was near the antenna cable, but that doesn't seem to be the problem. The key word in all this is "cheap". Anything over $10 is way out of line. Snuffy |
| whit3rd <whit3rd@gmail.com>: Jul 07 12:59PM -0700 On Tuesday, July 7, 2015 at 12:02:29 PM UTC-7, Snuffy Hub Cap McKinney wrote: > I have a analog TV that is still working fine and no plans to replace it. Over time, it has developed an audio hum - I'm guessing it's 60 Hz. When the picture is dark, the hum is nearly gone. Probably the HV flyback power and the audio (sound amplifiers) power are taken from a common filter capacitor, which has developed high internal resistance. If you can replace or bypass (put an auxiliary capacitor in parallel with the weak one), that should fix it. The hum is caused by voltage droop when the screen is lit, modulated at 60 Hz because the screen blanks for a while during vertical retrace. |
| John-Del <ohger1s@aol.com>: Jul 07 02:55PM -0700 On Tuesday, July 7, 2015 at 3:02:29 PM UTC-4, Snuffy Hub Cap McKinney wrote: > First I thought was a power cord was near the antenna cable, but that doesn't seem to be the problem. > The key word in all this is "cheap". Anything over $10 is way out of line. > Snuffy Are you sure it's coming from the speaker? Deflection yokes are known to hum as the mastic snot that locates the convergence shunts dry up from age. |
| "Snuffy \"Hub Cap\" McKinney" <Snuffy-Hub-Cap@Livebait-McKinney.com>: Jul 07 04:06PM -0700 "John-Del" <ohger1s@aol.com> wrote in message news:5783f073-6dc8-472f-95f3-bf16a8335e9d@googlegroups.com... On Tuesday, July 7, 2015 at 3:02:29 PM UTC-4, Snuffy Hub Cap McKinney wrote: > First I thought was a power cord was near the antenna cable, but that doesn't seem to be the problem. > The key word in all this is "cheap". Anything over $10 is way out of line. > Snuffy - Are you sure it's coming from the speaker? Deflection yokes are known to hum as the mastic snot that locates the convergence shunts dry up from age. Yes, the hum goes up and down with the volume. |
| "Snuffy \"Hub Cap\" McKinney" <Snuffy-Hub-Cap@Livebait-McKinney.com>: Jul 07 04:11PM -0700 "whit3rd" <whit3rd@gmail.com> wrote in message news:654d72c9-dfbe-4bb0-b4ec-6a5dc9bd847a@googlegroups.com... > that should fix it. > The hum is caused by voltage droop when the screen is lit, modulated at 60 Hz > because the screen blanks for a while during vertical retrace. Thanks, whit3rd. I would give it a try but unfortunatley for me, I don't have a schematic and not up on TV circuits. Not related to this... but have been meaning to ask.... I would like to pick up radio stations AM & FM that have weak signals. Is there a home-brew antenna method I can use for this? Like the TV, if there's something relatively simple and low cost I'd like to try it. Not worth more than a few dollars. |
| dplatt@coop.radagast.org (Dave Platt): Jul 07 04:39PM -0700 In article <5783f073-6dc8-472f-95f3-bf16a8335e9d@googlegroups.com>, > Are you sure it's coming from the speaker? Deflection yokes are > known to hum as the mastic snot that locates the convergence shunts > dry up from age. The fact that the hum amplitude changes with brightness, does suggest to me that the original suggestion is correct. I've heard this sort of brightness-varying hum from older TVs in the past, and it was definitely coming from the speakers. TVs are tough places for capacitors due to the internal heat... so, a dried-up filter cap is a good suspect. A lot of "60 Hz" hum or buzz from televisions actually has a lot of harmonic content - it's a long way from being a pure sinewave. A simple high-pass or notch filter to take out the 60 Hz won't be very effective in getting rid of the nuisance. |
| Chris Jones <lugnut808@spam.yahoo.com>: Jul 08 11:05AM +1000 On 08/07/2015 05:02, Snuffy "Hub Cap" McKinney wrote: > The key word in all this is "cheap". Anything over $10 is way out of > line. > Snuffy If you are receiving an analog signal (either from a transmitter or from a digital converter box) then you may just need to re-check the tuning to get rid of the hum. For each channel, the video and sound signals are transmitted on nearby frequencies, and if the tuning is slightly off, the video signal can get into the sound receiver, causing a buzz that changes with the picture content. If re-tuning doesn't fix it, maybe you can borrow an ESR meter and check for any dried up capacitors that might be resulting in ripple on a power supply rail, though I think this is unlikely to affect the sound without also affecting the picture. Chris |
| Clifford Heath <no.spam@please.net>: Jul 08 02:54AM +1000 On 08/07/15 09:11, Snuffy "Hub Cap" McKinney wrote: >> The hum is caused by voltage droop when the screen is lit, modulated at 60 Hz >> because the screen blanks for a while during vertical retrace. > Thanks, whit3rd. I would give it a try but unfortunatley for me, I don't have a schematic and not up on TV circuits. My vote is with this response; it'll be the power supply filter capacitors. > Not related to this... but have been meaning to ask.... I would like to pick up radio stations AM & FM that have weak signals. Is there a home-brew antenna method I can use for this? Like the TV, if there's something relatively simple and low cost I'd like to try it. Not worth more than a few dollars. Different solutions for AM and FM. For AM, run a long wire to the highest point you can. For FM, height matters too, but you need an antenna that resonates in the right frequency range. So does the use of good quality coaxial cable. If you can get an old TV balun, hook the 300 ohm side to the inner ends of two 75cm dipole elements, and run the coax down from that. Orient the dipole broadside to where your transmitters are. Both are quite easy homebrew jobs. |
| "Tom Miller" <tmiller11147@verizon.net>: Jul 07 11:37PM -0400 "Dave Platt" <dplatt@coop.radagast.org> wrote in message news:0i4u6c-kfl.ln1@coop.radagast.org... > harmonic content - it's a long way from being a pure sinewave. A > simple high-pass or notch filter to take out the 60 Hz won't be very > effective in getting rid of the nuisance. Not only that but it is more likely 120 Hz hum. |
| N_Cook <diverse@tcp.co.uk>: Jul 08 09:17AM +0100 On 07/07/2015 20:02, Snuffy "Hub Cap" McKinney wrote: > First I thought was a power cord was near the antenna cable, but that doesn't seem to be the problem. > The key word in all this is "cheap". Anything over $10 is way out of line. > Snuffy I would go with loose frame-deflection yoke coil, wash over with traditional copal varnish and allow to dry. |
| John-Del <ohger1s@aol.com>: Jul 08 04:16AM -0700 On Wednesday, July 8, 2015 at 4:17:40 AM UTC-4, N_Cook wrote: > > Snuffy > I would go with loose frame-deflection yoke coil, wash over with > traditional copal varnish and allow to dry. Although a common problem, OP responded that the noise tracks with the volume, so that leaves out mechanical considerations. |
| "Mark Zacharias" <mark_zacharias@labolgcbs.net>: Jul 08 07:01AM -0500 "John-Del" <ohger1s@aol.com> wrote in message news:4ec26c55-28b1-474a-b1b5-bf12c40fecc6@googlegroups.com... On Wednesday, July 8, 2015 at 4:17:40 AM UTC-4, N_Cook wrote: > > Snuffy > I would go with loose frame-deflection yoke coil, wash over with > traditional copal varnish and allow to dry. AGC problems can cause video to bleed over into the audio circuits. Mark Z. |
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