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sjoerd kaper <sjoerdkaper@gmail.com>: Nov 28 06:53AM -0800 Hallo,   Zit met een probleem. De Husqvarna automower 330x heeft ergens een kabelbreuk in zijn grensdraad. Het basisstation heeft een controle lampje wat blauw knippert, en de automower zelf meldt dat hij geen verbinding kan krijgen.   Nu is er op internet een filmpje te vinden, waarin een kabel detector gebruikt word. Hier word een kleine spanningsbron aangebracht(sender) en met een 2e apparaatje(reciever) loop je langs de grensdraad, totdat je signaal wegvalt. Zo ziet het erg eenvoudig uit om de kabelbreuk op te zoeken.   https://youtu.be/l1t8XXI_BI4   Heb een soortgelijk apparaatje aangeschaft. Zoals in deze video te zien is, probeer ik ook met de rode klem een grensdraad te koppelen, en met de zwarte klem vast te maken aan de aarde.(de aarde is een ijzeren pen die in de grond zit, heb ook geprobeerd met een schroevendraaier). Met de reciever krijg ik alleen pieptoon dichtbij de basisstation/sender, echter verder opzoek naar de grensdraad valt het geluid vrij meteen weg, en is er niet meer te horen.   Wie kan me helpen door te zeggen wat ik verkeerd doe?   Zie hieronder mijn filmpje   https://youtu.be/8RW5lmA5mCA   dank alvast! Sjoerd

John-Del <ohger1s@aol.com>: Nov 28 04:27AM -0800 On Thursday, November 26, 2015 at 8:15:09 PM UTC-5, jasper smith wrote: > Radio Shack has a home made clock kit. > https://www.radioshack.com/collections/maker-s-t-e-m   > It doesn't require bashing off the case of a store bought clock and putting it into a case, and calling it home made.   Heheh... If little Mo made the theremin kit, Obama would have thought the aliens were landing....

gregz <zekor@comcast.net>: Nov 28 07:48AM > megaphones both with and without this rubber ring on the > edge of the flared horn. Cannot seem to find it nowadays.   > Anyone?   It would only affect top frequency by diffraction. With a good flaring of the mouth, might not do anything with the sharp edge. These things don't have very good highs to begin with.   Greg

thekmanrocks@gmail.com: Nov 28 03:55AM -0800 GS wrote: "- show quoted text - It would only affect top frequency by diffraction. With a good flaring of the mouth, might not do anything with the sharp edge. These things don't have very good highs to begin with.   Greg "   ^^ The BEST explanation by far!! And that diagram I glimpsed a long time ago alluded to this. Thanks.

Micky <NONONOmisc07@bigfoot.com>: Nov 28 12:47AM -0500 On Thu, 19 Nov 2015 04:25:32 -0500, Micky <NONONOmisc07@bigfoot.com> wrote:   >15 inches, if 1/8 wavelengths are useful, is longer than the wire, i'm >pretty sure. (Someday I may find the wire on the floor in the corner >and I'll measure it. )   BTW, a friend just gave me another radio, second hand, that indeed does have a wire about 34 inches coming out the back, so some makers care about this. I think that's what it shows, even if it's not 30.   He bought it at a Goodwill store to dock his iphone or ipad but he says it doesnt' work. I don't have one to test with, but it also doesn't get many radio stations. It's also missing its AM antenna and the only source I have for a plug is maybe my auto burglar alarm from the previous car, which I'm saving for the next car. For the record it's an Imode model IP200A but I don't really plan to fix it   I posted mostly to say that its antenna was 34 inches, not just 15.

Leonardo Capossio <capossio.leonardo@gmail.com>: Nov 27 01:13PM -0800 > Is the heat sink hot when the unit shuts down? > Use your hand, if you can't keep your hand on the > Heat sink, its too hot.   It is hot...which makes me wonder. I will make more checks when I get the chance.

Leonardo Capossio <capossio.leonardo@gmail.com>: Nov 27 01:45PM -0800 El viernes, 27 de noviembre de 2015, 3:05:29 (UTC-3), Phil Allison escribió:   > It is a PTC "positive temp coefficient" thermistor (aka posistor) with a steep rise in resistance at 100C. The mute circuit in the Fender trips when the PTC device reaches 800 ohms and is rising steeply - so operates with a snap action.   > FYI: "PTC100" is not a part number, but a code used on the schem referring to the parts list.   > ... Phil   That explains a LOT. Thanks.

Phil Allison <pallison49@gmail.com>: Nov 27 07:43PM -0800 Leonardo Capossio wrote:     > That explains a LOT. Thanks.   ** BTW, the NTC10-15 shown in series with the AC power is used as an anti-surge device. It is mounted on the PCB, not inside the transformer.   At room temp it's a 10ohm resistor, falling to 0.2ohms at 5 amps current.   At switch-on it simply adds 10 ohms to the wiring on the primary side, limiting inrush surge currents so the fuse does not blow regularly.     .... Phil

bud-- <null@void.com>: Nov 27 11:20AM -0600 > last areas in the US where one may still get actual 2-phase power. 2-phase, 4-wire > power was developed primarily for heavy motor use in that era when the battle of AC > vs. DC was not yet settled and 3-phase power was barely a gleam in Tesla's Eye.   All multiphase came from Tesla. And AC was widely thought to be useless until Tesla. Tesla had patents for both 2-phase and 3-phase. Tesla patents also covered essentially all possible AC induction motor designs.   It is common to use 480/277V 3-phase wye as the power distribution in large buildings. Transformers from 480/277V to 208/120V are located throughout the building in electrical rooms. Transformers have 3-cores for the 3 phases. Small transformers may be simpler, with 2 cores T-connected (Scott). These cores run at true 2-phase. The disadvantage is the power factor on the cores is screwed up and they have to be derated.   > hot-to-Hot at a nominal 240V and hot-to ground at 120V. Single-phase as only 1/3 of the > total capacity is realized. All this is done in the single-phase transformer at the > sub-station, not the distribution transformer at the pole (vault) in the neighborhood.   For the houses in my area (and probably all of Minneapolis), a single 8kv L-N distribution leg is tapped off from the 13.8kv 3-phase wye distribution. Something like 4 blocks are fed from each tap. A pole mounted transformer feeds 240/120V to something like a block.

M Philbrook <jamie_ka1lpa@charter.net>: Nov 27 03:08PM -0500 In article <zICdnZ-PgMW5i8vLnZ2dnUU7-W2dnZ2d@earthlink.com>, rmowery28146@earthlink.net says...   > I hope that damn 2 phase 220 house wire does not start up again. There is a > true 2 phase and then then there is the split phase 240 that is common in > most of the houses in the US that some try to claim is 2 phase.   Show me the phase difference between your "TRUE" 2 phase and the "FALSE" 2 phase that you seem to know so much about.   I really want to know because I would like to see if you really understand what the term "PHASE" actually means?   Have a bad day..   Jamie

Jon Elson <elson@pico-systems.com>: Nov 27 02:23PM -0600 M Philbrook wrote:   > "FALSE" 2 phase that you seem to know so much about.   > I really want to know because I would like to see if you really > understand what the term "PHASE" actually means? There REALLY WERE, honestly, 2-phase systems in use quite some time ago. They had a 90 degree phase angle between the two phases. They could be delivered in a 3-wire system, looked just like split-phase 120/240, but were apparently commonly set up with 4 wires. The motors were wired with 2 windings in quadrature, and would start without any starting devices (switches, capacitors, etc.) just like a 3-phase motor. It was quickly figured out that 3-phase was slightly better (less torque ripple, for instance) and the 3-phase system took over.   Google "2 phase utility power" and they have an article on it.   Of course, standard residential power in the US is NOT 2-phase, but single- phase.   Jon

"Ralph Mowery" <rmowery28146@earthlink.net>: Nov 27 03:41PM -0500 "M Philbrook" <jamie_ka1lpa@charter.net> wrote in message news:MPG.30c28254915d4f7a989dc9@news.eternal-september.org... > "FALSE" 2 phase that you seem to know so much about.   > I really want to know because I would like to see if you really > understand what the term "PHASE" actually means?   I don't intend to get suckered into a long thread about the difference. All I am going to say is that by definition the 2 phase power is seperated by 90 deg instead of the 180 deg that the more common split phase is as some try to make it .   An easy way to tell is to hook a simple 2 wire iduction motor across the lines. If it starts, it is 2 phase, if not single phase. The single phase motor needs some means of starting such as a capacitor start circuit. That was one of the reasons 2 phase power was used.

"Ralph Mowery" <rmowery28146@earthlink.net>: Nov 27 03:43PM -0500 "Ralph Mowery" <rmowery28146@earthlink.net> wrote in message news:RfednfFowc14IMXLnZ2dnUU7-SOdnZ2d@earthlink.com... > lines. If it starts, it is 2 phase, if not single phase. The single > phase motor needs some means of starting such as a capacitor start > circuit. That was one of the reasons 2 phase power was used.   I ment to say 3 wires , not 2.

M Philbrook <jamie_ka1lpa@charter.net>: Nov 27 04:06PM -0500 In article <RfednfFowc14IMXLnZ2dnUU7-SOdnZ2d@earthlink.com>, rmowery28146@earthlink.net says... > lines. If it starts, it is 2 phase, if not single phase. The single phase > motor needs some means of starting such as a capacitor start circuit. That > was one of the reasons 2 phase power was used.       I thought so.   Jamie

bud-- <null@void.com>: Nov 27 11:58AM -0600 > This lamp was used by Zenith and more than a few other manufacturers in the 1950s/1960s as an indicator lamp (on/off) at about the time that radio manufacturers started to become concerned about user-servicing and hot-chassis radios - something that never really bothered them in the past. The worked on the theory that a neon lamp was far less likely to burn out than the old standby #44 or #47, so that loose fingers were less likely to get nipped. ASIDE: Audio devices held on to incandescent lamps (With specific reference to the 47) well into the 80s, before shifting - very slowly - to LEDs or Fluorescent lamps. But, they had transformers on board to isolate the chassis.   > It is designed to operate at ~120V AC. It _CAN_ operate at ~120V DC, but only one post will light. It will trip (glow) at about 90V +/-.   > Unless there is a voltage dropper in the circuit, it will fail quickly at 220 or 240 V - that is voltages outside of Japan and the Americas. As supplied, it has a 100K resistor in series with the lamp. For conversion to 220V, I have heard values of up to an *additional* 220K in series. Try there and work back if you wish to operate at 220V.   It will fail immediately without a series resistor. As others have said, there is no resistor built into the lamp.   From a 1965 Allied Radio catalog, Chicago Miniature lamp: NE-51 is clear glass tubular, single contact bayonet base. Voltage across the lamp is 65V when operating at the rated 1/25 watt.   A higher voltage is necessary to ionize the neon (which is why a relaxation oscillator works). The voltage is somewhat constant with varying current. At 1/25 watt and 65 volts the current would be 0.6 mA and the series resistor for 120V supply would be 91k (minimum).   There is also a NE-51H that runs at a blinding 1/7 watt (2 mA).

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