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"pfjw@aol.com" <pfjw@aol.com>: Sep 27 11:41AM -0700 On Tuesday, September 26, 2017 at 7:16:44 PM UTC-4, Dave Platt wrote:   Actually, consider the additional i in Aluminium, and all those Us such as colour, behaviour an more, going on since the days of Shakespeare and before.   If you allow a cost of GBP 0.01/100 such extra letters, and for round figures consider that the average number of printed & written such letters is around two billion per year, that comes to GBP 200,000 per year. Since about 1590. Consider the miracle of compound interest - and what that would be worth today, not including all the additional years. What a waste!   That initial 200,000 would be worth GBP 807,434,220 +/- today. Boggles the mind.   http://www.angelfire.com/va3/timshenk/codes/meihem.html   Peter Wieck Melrose Park, PA

rickman <gnuarm@gmail.com>: Sep 27 03:39PM -0400 > If you allow a cost of GBP 0.01/100 such extra letters, and for round figures consider that the average number of printed & written such letters is around two billion per year, that comes to GBP 200,000 per year. Since about 1590. Consider the miracle of compound interest - and what that would be worth today, not including all the additional years. What a waste!   > That initial 200,000 would be worth GBP 807,434,220 +/- today. Boggles the mind.   > http://www.angelfire.com/va3/timshenk/codes/meihem.html   The question is what is the cost of conversion? Tell you what. If the UK converts from colour to color and aluminium to aluminum and a few incidental others, the US will convert fully to metric. I think both are equally likely unfortunately.   --   Rick C   Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998

"pfjw@aol.com" <pfjw@aol.com>: Sep 27 12:52PM -0700 On Wednesday, September 27, 2017 at 3:39:23 PM UTC-4, rickman wrote:   > converts from colour to color and aluminium to aluminum and a few incidental > others, the US will convert fully to metric. I think both are equally > likely unfortunately.   There is no cost to delete letters in future printings. There are massive costs associated with retooling. Emphasis on "Future". Engraved plates, and so forth may be left as-is. It would be new plates and so forth that would realize the savings.   Peter Wieck Melrose Park, PA

tabbypurr@gmail.com: Sep 27 01:17PM -0700 > There is no cost to delete letters in future printings. There are massive costs associated with retooling. Emphasis on "Future". Engraved plates, and so forth may be left as-is. It would be new plates and so forth that would realize the savings.   > Peter Wieck > Melrose Park, PA   the imagined savings were based on 1p per letter, which has nothing to do with reality.     NT

hankvc@blackhole.lostwells.org (Hank): Sep 28 06:27AM In article <hiljsctonehbkmnnivrp1mu59osrc2j29t@4ax.com>,   >BTW: The 6 volt feeding them comes from the filament center tap in the >35Z5 rectifier tube. How they get 6volts from that center tap evades me, >but that's how it is.....   This looks to be the schematic for the set. It's an AA6, with an RF amplifier ahead of the converter. http://www.nostalgiaair.org/pagesbymodel/076/M0015076.pdf   We used to use schematics of sets like these back in the 1950's and '60's as interview questions for EE and technician canditates. One very good one was "talk to me about the rectifier circuit."   Understanding the circuit starts with understanding basic electricity, particularly Kirchoff's current law and Thévenin's theorem. What you are calling a "center tap" between pins 2-3 of a 35Z5 is at the 21.5% point of the heater, not the center. According to the RCA data sheets, with 35 volts between pins 2 and 7, you'll see 7.5 volts across pins 2-3. Now add a #47 (6.3v 150 ma.) bulb across pins 2 and 3, and feed the plate from pin 3. RCA claims that the voltage across pins 2-3 (and the bulb), with a 60 ma. draw on the cathode is now 5.5 volts and between pins 2-7, 32 volts.   That, of course, doesn't "add up." Assuming RMS values, a 150 ma. heater plus 60 ma. of DC is only 210 ma. RMS, which should explain the lower voltage between pins 2-3. However, also consider that current flow in the plate circuit, with a 40 mike cap connected to the cathode is a pulse, not a full half sine wave, and that RCA measurements were made with a VTVM, which isn't a "true RMS instrument." Those pulses, and the low thermal inertia of the pilot lamp filament(s) explains why the bulb is at full brilliance when the set is warmed up and playing.   Another "trick" to the series circuit is that during warmup, the series filaments are a voltage divider that is essentially constant for any current passing through the heater string. These heaters have a steep positive temperature (heat/ohms) coefficient, so the startup current is more like 1.5 amps. If you are going to fuse the radio, you need to measure the resistance of the filament string cold, and work from there.   That's for starters.   Now, as to the rest of the set, take a look at the B+ circuit and voltages. The tube data sheets give 100 volts on both plate and screen as "typical operation" points for AA5 tubes. However, this set says 76 volts. Also note that "typical operation" specs an initial bias (-1 volt for 12SK7), while this set has the cathodes of the RF tubes grounded.   Yes, that schematic is a very good interview subject.   Don't get foxed by "Mazda." That was a GE trademark from around 1910 to denote "tungsten filament," and was licensed by other bulb manufacturers. GE dropped using it in 1945. If you need bulbs, a 1490 is a 1490, readily available today.   If you are going to play the radio without recapping, the critical caps are the coupling caps between stages, particularly the cap feeding the audio power amp. Also, check the value of the grid leak resistor(s). You should see zero volts DC at the grid of the 35L6.   The AA5 (and AA6) are, with the DC-3 airplane, and the GG-1 locomotive, standout classics of American design. They look "simple" but there's a lot of thinking that made them robust and reliable without being complicated.   Hank

"Michael A. Terrell" <mike.terrell@earthlink.net>: Sep 28 06:55AM -0400 rickman wrote: > was not too long before the paint started to peel. I don't know the > type of plastic. It was a food storage container with a seal ring > commonly available in stores. Just a data point for what it is worth.     If you are talking about 'Tupperware' type containers, that plastic is the lowest grade available. It won't hold paint, and common adhesives won't stick to it.   -- Never piss off an Engineer!   They don't get mad.   They don't get even.   They go for over unity! ;-)

tabbypurr@gmail.com: Sep 28 05:48AM -0700 On Thursday, 28 September 2017 11:55:48 UTC+1, Michael Terrell wrote:   > If you are talking about 'Tupperware' type containers, that plastic > is the lowest grade available. It won't hold paint, and common adhesives > won't stick to it.   They're food grade. Nothing sticks to polythene unless you torch it first or weld it.     NT

oldschool@tubes.com: Sep 28 11:44AM -0400 On Thu, 28 Sep 2017 06:27:49 -0000 (UTC), hankvc@blackhole.lostwells.org (Hank) wrote:   >lot of thinking that made them robust and reliable without being >complicated.   >Hank   Thanks for the detailed explanation. I had a suspicion that the "center tap" of the rectifier tube was not actually CENTER. The more I work on these old sets, the more I notice that they are all pretty much the same, particularly if it's the same brand. One website I looked at, said that the chassis is a number -xxxx-. (I forget the number, but it was a 4 digit number 10__). I guess that means this same chassis was used in other RCA radios, not just these 66X_ (1 thru 4) models. But considering the years they were made, that makes sense. They produced the chassis and made numerous cabinets to fit around them.   I have to say that I am highly impressed that this 70 year old radio still works, with it's old caps and all. I have considered recapping it, or at least the critical caps and the power supply filter caps. But then again, "if it works, dont fix it". Having it power up with no hum, was what impressed me most, since the electrolytics are usually bad.   Thanks for explaining that "Mazda". That had me puzzled. In all the years I have worked on this stuff, that is the first time I saw that word used. I should have suspected it was a trademark....   That schematic is clearer and better than the one I had, so that will help too.

Robin Ingenthron <ingenthron@gmail.com>: Sep 28 08:56AM -0700 Our company is manufacturing backlight signs for restaurants, and our current process involves keeping the original TV power board to light the backpane.   We think the TV powerboard is "overkill" to just run the lights and also has more value sold for another TV.   Does anyone have experience with Universal power boards like these ones (sold on Alibaba)?   http://www.finder.com.cn/Products/Details/LCDPower.htm   Finally, what's the best vocabulary word when the OLED crystal sheet is removed and you have only the frame and compact fluorescent / LEDs?   backpane? backlight? backpanels? backplanes?   fairtraderecycling.org Robin at WR3A dot org

N_Cook <diverse@tcp.co.uk>: Sep 28 03:56PM +0100 On 27/09/2017 08:11, N_Cook wrote: > (ie not 1000 minimum) available, even then pp3 ones are about 10 times > too big. > I was thinking of a 5V supercap might work as a replacement, if necessary   I now see 3cell 20mAh NiMH are easily available, but if there is a next time I'll first try 5.6V (small diode in the charging line as-is)zener over the motor and a 5V supercap of similar volume

rickman <gnuarm@gmail.com>: Sep 28 11:09AM -0400 N_Cook wrote on 9/26/2017 2:22 PM: > But presumably it may return , unbalanced charge/discharge across the cells. > How to do the isolated charging of one cell properly, the next time in the > way of monitoring voltages and charge currents ?   Stick to lights with one cell.   --   Rick C   Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998

Roy Tremblay <rmblayrrroy@nlnet.nl>: Sep 28 07:25AM > back of my house, either on the block wall where it can be a bit sheltered > or on the wooden barge board for the flat roof out in the weather.   > Preferably with POE to minimise the mechanical farting around.   Hi Rod Speed & Jeff Liebermann,   I just set up a spare Ubiquiti Rocket M2 radio & 28dBi dish antenna in station/bridge mode, which is what Rod Speed needs if he wants to use the radio at his neighbor's house, to pick up the weak signal from Rod's SOHO Wi-Fi router. We tested this configuration at about 200 feet and got perfectly acceptable signal strength.   I also set up a Ubiquiti Rocket M5 in Access Point mode, which is what Rod Speed is most likely to do, but this post is only about how easy it is to set up the Ubiquiti radios in station/bridge mode to *receive* signal from a SOHO router Wi-Fi access point.   I'm using the Ubiquiti Rocket M2 in station/bridge mode right now, connected to a desktop PC Ethernet port and then picking up the signal from my SOHO WiFi router, which is exactly what Rod's neighbor would be using if Rod opts to put a receiving dish and bucket router on the neighbor's property facing Rod's home.   Here is a photo of the radios that I'm playing with for this test. <https://s26.postimg.org/62350hckp/00aradio.jpg>   Here is a photo of the radios set up in AP mode (where Rod Speed would broadcast his signal to his neighbor) and set up in station/bridge mode (where his neighbor would receive the weak signal from Rod Speed's SOHO WiFi router). <https://s26.postimg.org/kzbm1hpt5/00bradio.jpg>   Up until today, I was using a Mikrotik RB411/R52n-M radio to pick up the weak signal from the SOHO WiFi router. <https://s26.postimg.org/vanyu5hih/00cradio.jpg>   But we just got a set of spare Rocket M2 radios to play with so that's why I tested this out for Rod Speed. <https://s26.postimg.org/w1gozxjvt/00dradio.jpg>   For Rod Speed to test out what the neighbor would need to simply pick up the weak signal 300 feet away from Rod Speed's SOHO Wi-Fi router, here's all the neighbor needs to do.   1. Power up a Windows 10 PC (that's what I tested this on). 2. Connect the Ubiquiti Rocket M2 radio to the POE power "POE" port. 3. Reset the Ubiquiti radio to factory defaults (if needed). 4. Set the Windows 10 PC to a static IP address of 192.168.1.x (where x is anything not used, and not 20). 5. Connect the POE power supply LAN port to the Windows PC Ethernet port. 6. Log into the Ubiquiti radio at http://192.168.1.20 using the default login of "ubnt" and the password of "ubnt". 7. The radio will force you to set the country code & language and it will force you to accept the EULA checkbox. 8. The radio will force you to change the password, where it will take anything other than "ubnt" (e.g., "Ubnt" works just fine). 9. Go to the NETWORK tab and hit the "Select" button and select the SSID broadcast from the SOHO Wi-Fi router & enter the type of security and passphrase for that access point. 10. Hit "change" and "apply" and that's it. You're done!   The Windows 10 PC is now connected to the SOHO Wi-Fi router weak signal, and the Windows 10 PC is therefore instantly on the Internet.   In practice, the user can test this out at home, and then move the radio 300 feet away from the SOHO Wi-Fi router where the radio should still work pretty far out to connect to the weak SOHO router Wi-Fi signal.   Once the user establishes this works at 100 feet, 200 feet, 300 feet, etc., they can just put a router on the end of the radio, and they can wired or wirelessly connect any device they want to that router (such as a barn cam).   Here are screenshots of the relevant screens in the setup, but again, it's very simple because there is only one change that is required which is to set the radio to pick up the correct SOHO router Wi-Fi access point SSID, security type, and passphrase.   radio_001.jpg <https://s26.postimg.org/54wprm12h/radio_001.jpg>   radio_002.jpg <https://s26.postimg.org/dbopj6r55/radio_002.jpg>   radio_003.jpg <https://s26.postimg.org/d1h6zucix/radio_003.jpg>   radio_004.jpg <https://s26.postimg.org/9j573gbmx/radio_004.jpg>   radio_005.jpg <https://s26.postimg.org/6dkld8t0p/radio_005.jpg>   radio_006.jpg <https://s26.postimg.org/aa2z6ckbt/radio_006.jpg>   radio_007.jpg <https://s26.postimg.org/csoo71621/radio_007.jpg>   radio_008.jpg <https://s26.postimg.org/brofhwp2h/radio_008.jpg>   radio_009.jpg <https://s26.postimg.org/6uauwsn3d/radio_009.jpg>

Roy Tremblay <rmblayrrroy@nlnet.nl>: Sep 28 08:09AM > I also set up a Ubiquiti Rocket M5 in Access Point mode, which is what Rod > Speed is most likely to do   Here are the screenshots of the setup to set this Ubiquiti Rocket M5 in the mode that Rod Speed wants.   In this setup, the radio will hang off his SOHO router by cat5 cable and POE, and then this access point will paint the next few miles with his Internet signal such that a neighbor only a few hundred feet away should be able to connect to this powerful access point with small devices. https://s26.postimg.org/kzbm1hpt5/00bradio.jpg   This happens to be a 5GHz 30 decibel rocket, but the procedure is exactly the same no matter what Ubiquiti radio Rod Speed chooses to make his access point that paints the neighbor's home (as per the calculations from Jeff).   ap_001 Security Certificate override at 192.168.1.20 (default) https://s26.postimg.org/xcpkferk9/ap_001.jpg   ap_002 Log in to 192.168.1.20 port 80 as ubnt/ubnt https://s26.postimg.org/rd1tbr6rt/ap_002.jpg   ap_003 Make sure AirMAX is not enabled https://s26.postimg.org/dkneg4g09/ap_003.jpg   ap_004 You should be in Access Point/Bridge mode https://s26.postimg.org/pnsq3or2h/ap_004.jpg   ap_005 Choose the SSID & security & channel & width you want for the AP https://s26.postimg.org/hwc054mx5/ap_005.jpg   ap_006 Choose any static IP address that you want for 192.168.1.whatever https://s26.postimg.org/4gozfoefd/ap_006.jpg   ap_007 There's nothing to change on the Advanced tab https://s26.postimg.org/69rw3zzm1/ap_007.jpg   ap_008 There's nothing to change on the Services tab https://s26.postimg.org/zdg408npl/ap_008.jpg   ap_009 There's nothing to change on the System tab https://s26.postimg.org/hood8mbyh/ap_009.jpg

Roy Tremblay <rmblayrrroy@nlnet.nl>: Sep 28 07:29AM > But until then, this is how to set up a Ubiquiti 2.4GHz radio to pick up > the SOHO router from 200 feet away from the house.   I simplified and documented the procedure better because I just set up a spare Ubiquiti Rocket M2 radio & 28dBi dish antenna in station/bridge mode, which is what Rod Speed needs if he wants to use the radio at his neighbor's house, to pick up the weak signal from Rod's SOHO Wi-Fi router. We tested this configuration at about 200 feet and got perfectly acceptable signal strength.   I also set up a Ubiquiti Rocket M5 in Access Point mode, which is what Rod Speed is most likely to do, but this post is only about how easy it is to set up the Ubiquiti radios in station/bridge mode to *receive* signal from a SOHO router Wi-Fi access point.   I'm using the Ubiquiti Rocket M2 in station/bridge mode right now, connected to a desktop PC Ethernet port and then picking up the signal from my SOHO WiFi router, which is exactly what Rod's neighbor would be using if Rod opts to put a receiving dish and bucket router on the neighbor's property facing Rod's home.   Here is a photo of the radios that I'm playing with for this test. <https://s26.postimg.org/62350hckp/00aradio.jpg>   Here is a photo of the radios set up in AP mode (where Rod Speed would broadcast his signal to his neighbor) and set up in station/bridge mode (where his neighbor would receive the weak signal from Rod Speed's SOHO WiFi router). <https://s26.postimg.org/kzbm1hpt5/00bradio.jpg>   Up until today, I was using a Mikrotik RB411/R52n-M radio to pick up the weak signal from the SOHO WiFi router. <https://s26.postimg.org/vanyu5hih/00cradio.jpg>   But we just got a set of spare Rocket M2 radios to play with so that's why I tested this out for Rod Speed. <https://s26.postimg.org/w1gozxjvt/00dradio.jpg>   For Rod Speed to test out what the neighbor would need to simply pick up the weak signal 300 feet away from Rod Speed's SOHO Wi-Fi router, here's all the neighbor needs to do.   1. Power up a Windows 10 PC (that's what I tested this on). 2. Connect the Ubiquiti Rocket M2 radio to the POE power "POE" port. 3. Reset the Ubiquiti radio to factory defaults (if needed) (just hold the reset switch, under power, until the lights all flash). 4. Set the Windows 10 PC to a static IP address of 192.168.1.x (where x is anything not used, and not 20). 5. Connect the POE power supply LAN port to the Windows PC Ethernet port. 6. Log into the Ubiquiti radio at http://192.168.1.20 using the default login of "ubnt" and the password of "ubnt". 7. The radio will force you to set the country code & language and it will force you to accept the EULA checkbox. 8. The radio will force you to change the password, where it will take anything other than "ubnt" (e.g., "Ubnt" works just fine). 9. Go to the NETWORK tab and hit the "Select" button and select the SSID broadcast from the SOHO Wi-Fi router & enter the type of security and passphrase for that access point. 10. Hit "change" and "apply" and that's it. You're done!   The Windows 10 PC is now connected to the SOHO Wi-Fi router weak signal, and the Windows 10 PC is therefore instantly on the Internet.   In practice, the user can test this out at home, and then move the radio 300 feet away from the SOHO Wi-Fi router where the radio should still work pretty far out to connect to the weak SOHO router Wi-Fi signal.   Once the user establishes this works at 100 feet, 200 feet, 300 feet, etc., they can just put a router on the end of the radio, and they can wired or wirelessly connect any device they want to that router (such as a barn cam).   Here are screenshots of the relevant screens in the setup, but again, it's very simple because there is only one change that is required which is to set the radio to pick up the correct SOHO router Wi-Fi access point SSID, security type, and passphrase.   radio_001.jpg <https://s26.postimg.org/54wprm12h/radio_001.jpg>   radio_002.jpg <https://s26.postimg.org/dbopj6r55/radio_002.jpg>   radio_003.jpg <https://s26.postimg.org/d1h6zucix/radio_003.jpg>   radio_004.jpg <https://s26.postimg.org/9j573gbmx/radio_004.jpg>   radio_005.jpg <https://s26.postimg.org/6dkld8t0p/radio_005.jpg>   radio_006.jpg <https://s26.postimg.org/aa2z6ckbt/radio_006.jpg>   radio_007.jpg <https://s26.postimg.org/csoo71621/radio_007.jpg>   radio_008.jpg <https://s26.postimg.org/brofhwp2h/radio_008.jpg>   radio_009.jpg <https://s26.postimg.org/6uauwsn3d/radio_009.jpg>

Roy Tremblay <rmblayrrroy@nlnet.nl>: Sep 28 08:08AM > I also set up a Ubiquiti Rocket M5 in Access Point mode, which is what Rod > Speed is most likely to do   Here are the screenshots of the setup to set this Ubiquiti Rocket M5 in the mode that Rod Speed wants.   In this setup, the radio will hang off his SOHO router by cat5 cable and POE, and then it will paint the next few miles with his Internet signal such that a neighbor only a few hundred feet away should be able to connect to this powerful access point with small devices. https://s26.postimg.org/kzbm1hpt5/00bradio.jpg   This happens to be a 5GHz 30 decibel rocket, but the procedure is exactly the same no matter what Ubiquiti radio Rod Speed chooses to make his access point that paints the neighbor's home (as per the calculations from Jeff).   ap_001 Security Certificate override at 192.168.1.20 (default) https://s26.postimg.org/xcpkferk9/ap_001.jpg   ap_002 Log in to 192.168.1.20 port 80 as ubnt/ubnt https://s26.postimg.org/rd1tbr6rt/ap_002.jpg   ap_003 Make sure AirMAX is not enabled https://s26.postimg.org/dkneg4g09/ap_003.jpg   ap_004 You should be in Access Point/Bridge mode https://s26.postimg.org/pnsq3or2h/ap_004.jpg   ap_005 Choose the SSID & security & channel & width you want for the AP https://s26.postimg.org/hwc054mx5/ap_005.jpg   ap_006 Choose any static IP address that you want for 192.168.1.whatever https://s26.postimg.org/4gozfoefd/ap_006.jpg   ap_007 There's nothing to change on the Advanced tab https://s26.postimg.org/69rw3zzm1/ap_007.jpg   ap_008 There's nothing to change on the Services tab https://s26.postimg.org/zdg408npl/ap_008.jpg   ap_009 There's nothing to change on the System tab https://s26.postimg.org/hood8mbyh/ap_009.jpg

mogulah@hotmail.com: Sep 27 11:41AM -0700 "While they have not put forward an alternative explanation for the explosion, outlandish theories in the past have included a massive volcanic eruption, a comet mainly composed of ice not solid space rock, a black hole colliding with Earth and even aliens shooting down a meteor from a UFO in order to save Earth."   Mystery Deepens Over World's Biggest Explosion In Russia Daily Mail - January 23, 2017 -- http://www.dailymail.co.uk/news/article-4147034/Mystery-deepens-world-s-biggest-explosion-Russia.html

N_Cook <diverse@tcp.co.uk>: Sep 27 08:32PM +0100 > Mystery Deepens Over World's Biggest Explosion In Russia > Daily Mail - January 23, 2017 > -- http://www.dailymail.co.uk/news/article-4147034/Mystery-deepens-world-s-biggest-explosion-Russia.html   What was so mysterious about the Chelyabinsk meteor ? https://en.wikipedia.org/wiki/Chelyabinsk_meteor   I suppose they did not have dashboard cams 100 years ago for a slightly larger meteor Earth-grazing air-burst event

Allodoxaphobia <knock_yourself_out@example.net>: Sep 28 02:01AM On Wed, 27 Sep 2017 20:32:07 +0100, N_Cook wrote: > https://en.wikipedia.org/wiki/Chelyabinsk_meteor   > I suppose they did not have dashboard cams 100 years ago for a slightly > larger meteor Earth-grazing air-burst event   And this has what all to do with sci.electronics.repair?????????

rickman <gnuarm@gmail.com>: Sep 27 10:30PM -0400 Allodoxaphobia wrote on 9/27/2017 10:01 PM:   >> I suppose they did not have dashboard cams 100 years ago for a slightly >> larger meteor Earth-grazing air-burst event   > And this has what all to do with sci.electronics.repair?????????   Don't you think aliens are going to want their equipment repaired????????   Oh, that should be in sci.electronics.repair.alien... Sorry, my bad.   --   Rick C   Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998

N_Cook <diverse@tcp.co.uk>: Sep 28 08:22AM +0100 On 28/09/2017 03:30, rickman wrote:   >> And this has what all to do with sci.electronics.repair?????????   > Don't you think aliens are going to want their equipment repaired????????   > Oh, that should be in sci.electronics.repair.alien... Sorry, my bad.   But the paranoid android got by , not repairing all the painful diodes down his left side.

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