- SMD Fuse ID - 1 Update
- SMD Fuse ID - 1 Update
- Technics SU-610, one channel down? - 1 Update
- Sony STR-KS360 Display Dim - 7 Updates
- CEN-TECH 10/2/50A 12v Manual Charger Burned out - 5 Updates
- can't figure correct resistance for teflon coated copper wire - 7 Updates
| KenW <ken1943@invalid.net>: Oct 31 10:33AM -0600 On Sat, 31 Oct 2020 12:26:25 -0400, ABLE1 <somewhere@nowhere.net> wrote: >I am prepared for the best and worst. >Thank you very much in advance. >Les Because they are cheap and can be wave soldered and last but not least screw the buyer. KenW |
| ABLE1 <somewhere@nowhere.net>: Oct 31 12:26PM -0400 Hello, I have a circuit board that has a blown Fuse. The Fuse is a very small SMD device that is mounted to the board. The device is a color green if that matters with a capital "B" on the surface. This is just a curiosity question for my own edification and maybe for the benefit others. Is there some chart that would be available to give the ability to ID the value of this fuse and its parameters?? Then my other comment has a different tone. Personally I think fuses of this design are a PITA. Yes, it is smaller and makes for a "clean look" but when one might have been blown by a possible spike on the line voltage in order to save the rest of the board then the WHOLE board need to be replaced. So then what is the point other than making more money. If it seems that I might sound a bit frazzed, that would be correct. I just don't understand the designing of this technology type especially at a input voltage of 120VAC. I am sure I will be enlightened to the whys and wherefores. I am prepared for the best and worst. Thank you very much in advance. Les |
| T i m <news@spaced.me.uk>: Oct 31 01:51PM Hi all, Chatting to a mate the other day and in passing mentioned his old Technics SU-610 amp, seems to have lost one channel and might I be able to fix it (I've just fixed a car battery charger for him). ;-) He said if he turns the balance fully to that channel and the volume fully up, he can just hear something from that speaker. I've suggested he try some tests ... actioning all the switches, swapping the input leads over L/R, trying a different input, checking the speaker connections / swapping the speakers, trying the headphone socket etc and to let me know the outcome. If it proves to be faulty and it comes to me, I've picked up one of those PC USB scopes (It was bought by my mate for his PC shop but mainly used by me there ... and he's not used it since he retired) and so I just need a signal source (any simple sine wave generator kits out there?), the schematic (got) and I'm good to go. The schematic looks pretty simple (even for me <g>) but I'm guessing it's likely to be the main hybrid amp module, an SVI3102B and I see they are still available for not a lot of money (new / used). Along with the basic tone generator question, does anyone know this model and is aware of any 'typical' fault causes / weaknesses / mods please? Cheers, T i m |
| Pat <forums@greensdomain.com>: Oct 30 01:38PM -0400 Hello, I am have a Sony STR-KS360 5.1 AV receiver I purchased 10 or 11 years ago. It still works well except the display is very dim. It can only be seen if the room is completely dark. The left 10% of the display is a little brighter than the right 90%, but even the brighter part is very dim. A few years back, I did some Google'ing and found I wasn't the only one having this issue. If I recall correctly, someone suggested a bad electrolytic as being the likely cause, but I was busy at the time and dropped it. Now, I'm retired and have some time to investigate. Anyone know which cap is the likely culprit? I can't find the old post I had read a few years ago. (My only available test equipment is a Fluke 87, but I can solder small components). The receiver has a "dim display" function, but it is set to off. The display gets even dimmer when I turn it on. Thanks, Pat |
| "Peter W." <peterwieck33@gmail.com>: Oct 30 11:06AM -0700 You will need to find the schematic, and from that trace the display driver power-supply. That should give you what you need. Alternately, you could shotgun all the electrolytics around the display board and hope to get lucky. HiFi Engine (free) should have the manual, so I would suggest the first expedient rather than the second. Peter Wieck Melrose Park, PA |
| Andy Burns <usenet@andyburns.uk>: Oct 30 06:20PM Pat wrote: > I am have a Sony STR-KS360 5.1 AV receiver I purchased 10 or 11 years > ago. It still works well except the display is very dim. The PCB for the display board is marked "FL700 FLUORESCENT INDICATOR TUBE" which to me implies a vacuum fluorescent display, I find these tend to have a maybe 5 year "half-life" of brightness? Attempting to "rejuvenate" the display might be kill or cure <https://www.eevblog.com/forum/chat/vacuum-fluorescent-display-rejuvenation> |
| dplatt@coop.radagast.org (Dave Platt): Oct 30 01:38PM -0700 In article <3siopfdkuju36jr5gcdi542rsgn6v4snh6@4ax.com>, >a Fluke 87, but I can solder small components). The receiver has a >"dim display" function, but it is set to off. The display gets even >dimmer when I turn it on. Unfortunately, this may turn out to be unrepairable in practice. This receiver uses a VFD (a vacuum fluorescent display). These are, in their essence, small specialized vacuum tubes, with a filament, a bunch of control grids, and a bunch of anodes coated with fluorescent material. These tubes wear out with time and use - the filament ages (its ability to emit electrons decreases) and the anodes age (the fluorescent material emits less and less light when struck by electrons). Eventually they go dark. The problem is worse for products which leave the VFD powered up (filament heated and drive voltage applied) even when the product is "turned off" - to show a clock, or an "Off" indication, or something like that. The VFD tubes were usually custom-made for one specific product, or for a product family. Finding an off-the-shelf replacement is probably not going to be possible. It's doubtful that Sony would even sell you a replacement VFD tube if they have one - their "smallest field serviceable spare part" is probably the whole display-panel PC board (which might still be available). Now, it's possible that the problem could be capacitor-related, I suppose. This receiver derives the high voltage for the tubes using a DC-to-DC converter (oscillator plus transformers and rectifiers and filter caps). There are a couple of electrolytic filter caps on the display board (C703 and C706) as part of this circuit - if one of them has "gone leaky" it might be dragging down the voltage supply to the tube and its driver IC and compromise the brightness. Checking and replacing these caps _might_ help, but I don't think the chances are very good. HiFiEngine.com has the service manual (free registration required). |
| abrsvc <dansabrservices@yahoo.com>: Oct 30 02:40PM -0700 On Friday, 30 October 2020 16:39:13 UTC-4, Dave Platt wrote: > Checking and replacing these caps _might_ help, but I don't think the > chances are very good. > HiFiEngine.com has the service manual (free registration required). Resolder all of the pins on the display as well. These can crystalize and increase resistance. I have successfully recovered a few this way. Also check the power supply for proper voltage levels. Here too it may be a simple fix. I would expect the display to last longer than this. |
| Pat <forums@greensdomain.com>: Oct 31 09:20AM -0400 On Fri, 30 Oct 2020 13:38:19 -0400, Pat <forums@greensdomain.com> wrote: >dimmer when I turn it on. >Thanks, >Pat Thank you to all who responded. I registered at HiFiEngine.com and downloaded the service manual. What a great resource. I'll open it up soon and see what I can find. Andy, the link you provided returns a 404 error, but I assume your statement of, "Attempting to rejuvenate the display might be kill or cure." summarizes it. I'll let you know what I find. Thanks, Pat |
| Andy Burns <usenet@andyburns.uk>: Oct 31 01:29PM Pat wrote: > Andy, the link you provided returns a 404 error Ah sorry, stick a trailing slash on the URL, I didn't copy it in full |
| "Peter W." <peterwieck33@gmail.com>: Oct 30 11:07AM -0700 Boo |
| Edward Hernandez <dtgamer99@gmail.com>: Oct 30 10:11PM > BOO! "Language is impossible," says Derrida; however, according to Parry, it is not so much language that is impossible, but rather the economy, and subsequent fatal flaw, of language. It could be said that any number of theories concerning materialist cultural theory exist. Debord's critique of the subpatriarchial paradigm of expression holds that truth is unattainable, given that culture is equal to reality. In a sense, Foucault uses the term 'Foucaultist power relations' to denote the role of the observer as poet. Baudrillard promotes the use of the subpatriarchial paradigm of expression to attack and analyse society. Modernism states that class has intrinsic meaning. However, the genre, and some would say the meaninglessness, of modernism prevalent in Erotica emerges again in Sex, although in a more self-referential sense. The subject is interpolated into a capitalist paradigm of discourse that includes language as a whole. A number of narratives concerning materialist cultural theory may be found. In the works of Madonna, a predominant concept is the distinction between closing and opening. The subject is contextualised into a that includes sexuality as a whole. If the subpatriarchial paradigm of expression holds, we have to choose between materialist cultural theory and dialectic Marxism. "Culture is part of the dialectic of consciousness," says Lyotard. Thus, Hamburger holds that we have to choose between materialist cultural theory and modernism. The primary theme of Long's critique of Sontagist camp is the rubicon of preconceptualist sexual identity. If one examines constructive nihilism, one is faced with a choice: either accept the subpatriarchial paradigm of expression or conclude that academe is capable of intention, but only if the premise of modernism is valid. The subpatriarchial paradigm of expression implies that society, perhaps ironically, has significance. Therefore, Bataille uses the term 'materialist cultural theory' to denote a textual totality. Marx suggests the use of the subcultural paradigm of reality to attack hierarchy. Many theories concerning modernism exist. The without/within distinction depicted in Material Girl is also evident in Erotica. Derrida's essay on the subpatriarchial paradigm of expression states that concensus comes from the collective unconscious, given that narrativity is distinct from art. But Lacan uses the term 'materialist cultural theory' to denote not discourse per se, but postdiscourse. Thus, the main theme of Hamburger's model of modernism is the common ground between sexual identity and class. Werther suggests that we have to choose between cultural deconstruction and the subpatriarchial paradigm of expression. In a sense, the subject is interpolated into a that includes truth as a paradox. Debord promotes the use of materialist cultural theory to deconstruct hierarchy. Several narratives concerning not, in fact, narrative, but neonarrative exist. However, Baudrillard uses the term 'modernism' to denote the failure, and eventually the collapse, of subdialectic sexual identity. It could be said that if the subpatriarchial paradigm of expression holds, the works of Joyce are reminiscent of Lynch. The premise of materialist cultural theory suggests that the raison d'etre of the poet is social comment. |
| Fox's Mercantile <jdangus@att.net>: Oct 30 05:20PM -0500 On 10/30/20 5:11 PM, Edward Hernandez wrote: > "Language is impossible," says Derrida; More cut and paste from a clown that has no comprehension of what they're copying and pasting. -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com |
| Jesse A. Minix <JesseAMinix@dayrep.com.invalid>: Oct 31 03:31AM > started with "Harbor Freight". Purchase a charger from a legitimate > source made by a legitimate manufacturer, rated for the intended > purpose and you will be fine." This is fine advice. It clearly was not the advice you felt you were entitled to receive, but it was still useful advice. |
| Fox's Mercantile <jdangus@att.net>: Oct 31 02:00AM -0500 On 10/30/20 10:31 PM, Jesse A. Minix wrote: > This is fine advice. It clearly was not the advice you felt you were > entitled to receive, but it was still useful advice. That's what we've been trying to get across to him all along. -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com |
| Ralph Mowery <rmowery28146@earthlink.net>: Oct 30 01:21PM -0400 In article <593b6d9c-02ba-4ec4-b3fd-8a69353caa17n@googlegroups.com>, peterwieck33@gmail.com says... > Hmmmm... If it is sufficiently important to know the precise and accurate resistance of a given (and very short) length of wire, then that method will not work very well. I have never, ever come across a factory-sealed spool of electrical wire that is within even 1% of the nominal length, with the tendency to run a bit long rather than short. And even shop-cut lengths tend to have a bit added for waste and crimps. > And here is another issue: I keep a pretty good Fluke meter which gives a resolution of +/-0.5% in ohms in ranges above 32 ohms, and +/- 2% at the lowest range. Which may not be good enough in this application. > Again, if it is sufficiently important, then the correct instrumentation and the calibration and set-up of same is critical. For most at home the best way for very low resistance is to have an ampmeter and voltmeter and varitable power supply. Put as much current as you can through the wire and measure the voltage across it and ohm law the resistance. |
| Runner <runners@aolnospam.com>: Oct 30 01:30PM -0400 On 10/30/20 1:21 PM, Ralph Mowery wrote: > ampmeter and voltmeter and varitable power supply. Put as much current > as you can through the wire and measure the voltage across it and ohm > law the resistance. This is what I ended up doing, although I decided to just power the entire 60 foot spool instead of the single one foot piece. I found that, at 12 V, 7 A was used, so that's where I started. That was too much power, at least IMO, for the electric blanket I was making, so I kept checking current and voltage until a more reasonable 55 W was reached. This meant using 20 feet of the wire and powering at 5 V (11 A). I'm under the blanket now and it's toasty. Not hot, but warm. I will be continuing to check connections for excess heating, but I repurposed the original Sunbeam connections and those are more than adequate and saved me a lot of time. The only source of moderate heating outside the blanket is the power wires to the blanket. Since I used the Sunbeam wires, their gauge is a bit thin. If it becomes an issue, I will upgrade to a thicker cable. The Teflon wire is hot glued to the old blanket. I wasn't sure if this would work as I feared glue melting, but so far so good after some hours. At 84 watts though, it might have been a different story. Originally, I was going to go with the full wire spool and the 84 watt version, but I wasn't sure how I was going to vary the output. All I have on hand was a PWM 8 A 12 V lamp dimmer, used for dimming LED arrays, but it burned out almost instantly. I wasn't surprised of course, but thought I'd give it a try. Any ideas as to how to vary the power welcome. |
| "Peter W." <peterwieck33@gmail.com>: Oct 30 10:30AM -0700 Yep. All within the accuracy range of the instruments. Which compound, not cancel, when multiple instruments are involved. Peter Wieck Melrose Park, PA |
| legg <legg@nospam.magma.ca>: Oct 30 04:08PM -0400 On Thu, 29 Oct 2020 21:55:51 -0400, Runner <runners@aolnospam.com> wrote: >the resistance of a one foot piece, but both of my meters read >differently. How can I get a reliable reading? I am using DVMs. >Thanks in advance. Run an amp through it and measure the voltage drop - same principle as many older micro-ohmeters. Helps if you have a fairly precise amp. Get to use all your meter ranges and sockets, in the process. Lots of room for mistakes, though. RL |
| Tim R <timothy42b@aol.com>: Oct 30 01:05PM -0700 On Friday, October 30, 2020 at 1:30:43 PM UTC-4, Runner wrote: > I'm under the blanket now and it's toasty. Not hot, but warm. I will > The Teflon wire is hot glued to the old blanket. I wasn't sure if this > would work as I feared glue melting, but so far so good after some Dude! I just..........I mean it boggles the mind. You made your own electric blanket with hot glue and duct tape, and you're trusting your life to it? I hope you live alone. I'm pretty sure you made your own smoke alarms but still. #darwinawards |
| Runner <runners@aolnospam.com>: Oct 30 05:16PM -0400 On 10/30/20 4:05 PM, Tim R wrote: >> The Teflon wire is hot glued to the old blanket. I wasn't sure if this >> would work as I feared glue melting, but so far so good after some > Dude! I just..........I mean it boggles the mind. You made your own electric blanket with hot glue and duct tape, and you're trusting your life to it? Not duck tape, hot glue only. Well, if you can demonstrate to me a name brand that lasts more than part of one season, I would buy it. I've bought several Sunbeams and all were returned/ exchanged because they don't last. I also went with Biddleford and same thing. Bought blankets today are junk and I am on limited income to keep shelling out for them. > I hope you live alone. I'm pretty sure you made your own smoke alarms but still. I didn't mention the power supply, but it has overload protection along with current sense, which is adjustable. If the blanket suddenly starts drawing more than it should, the power goes off. There are also fast blow fuses on both lines. |
| Jeff Liebermann <jeffl@cruzio.com>: Oct 30 09:17PM -0700 On Fri, 30 Oct 2020 13:30:37 -0400, Runner <runners@aolnospam.com> wrote: >This is what I ended up doing, although I decided to just power the >entire 60 foot spool instead of the single one foot piece. I found >that, at 12 V, 7 A was used, so that's where I started. You did that through a 1 ft length of wire? P = E * I = 12v * 7A = 84 watts In a 1 ft length of wire, that should have gotten the wire red hot (depending on wire gauge and contract resistance). >making, so I kept checking current and voltage until a more reasonable >55 W was reached. This meant using 20 feet of the wire and powering at >5 V (11 A). I have a small complaint. If you expect usable answers, it's really helpful if you would describe: 1. What problem are you trying to solve? 2. What do you have to work with? 3. What have you done so far and what went wrong? My initial reply assumed that you were doing some kind of measurement. I replied accordingly with the instruments required. My answer would have been very different if you had supplied the details and numbers. >blanket is the power wires to the blanket. Since I used the Sunbeam >wires, their gauge is a bit thin. If it becomes an issue, I will >upgrade to a thicker cable. Hint: Real electric blankets use nichrome or some form of resistance heating wire. See list at step 6. "DIY Heating Pad - (small Electrical Blanket)" <https://www.instructables.com/DIY-Heating-pad-small-electrical-blanket/> Any clues as to the source and tupe of "teflon insulated wire" you're using? If its copper wire, be advised that soft copper wire work hardens fairly easily. Just bend it a few times and it will break. >The Teflon wire is hot glued to the old blanket. The wire is not made of teflon. It's probably copper, nichrome, or something similar. The insulation is Teflon. Make sure you're using high temp (195C gun) glue. Low temp (130C gun) will work, but methinks high temp is a better choice. >I wasn't sure if this >would work as I feared glue melting, but so far so good after some >hours. The standard high temp hot melt glue melts at about 200C. That's quite a bit warmer than the 25C to 55C range of a typical electric blanket. >At 84 watts though, it might have been a different story. Queen size electric blankets typically draw about 60 watts or 100 watts for a twin size. >Originally, I was going to go with the full wire spool and the 84 watt >version, but I wasn't sure how I was going to vary the output. A light dimmer should work. If you try to use a linear regulator, you'll end up dissipating quite a bit of heat in the regulator. The switching regulator in the light dimmer is far more efficient. >All I >have on hand was a PWM 8 A 12 V lamp dimmer, used for dimming LED >arrays, but it burned out almost instantly. It should have worked. However, when the wire is cold, the resistance is rather low and the inrush current is rather high. When it gets warm, the resistance increases, and the operating current is reduces. My guess(tm) is that the initial inrush current exeeded the 8A rating. >I wasn't surprised of >course, but thought I'd give it a try. Learn by Destroying(tm). Ok, what have you learned? >Any ideas as to how to vary the power welcome. Nope. I can't do much without detailed specs on the wire. - 25C resistance/ft - 60C resistance/ft - Type of wire used. - Length of wire used. - Estimated blanket insulation value. - Thermostat system used. - Power source. 12V, 117VAC, or variable power supply? - Over-temperature protection (thermal fuse)? A Google search might help: <https://www.google.com/search?q=electric+blanket+controller> The commercial controllers usually have the power control and temperature regulating devices included. If one of the controllers from your failed blankets is still available, it might be worth testing and trying. Or, roll your own: <https://www.qsl.net/ve3lny/blanketcontroller.html> Note that the design is for a 117VAC blanket, not 12V. Be careful and have a fire extinguisher handy. -- 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 |
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