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jurb6006@gmail.com: Feb 09 04:23AM -0800 I have a small Sony in the bedroom. When I watch, I usually do it with the closed captions on. i have no need for music on TV, plus you can hardly understand the dialog, and some shit is just plain old annoying.   It overscans. Part of the reason is a bad cap. If the circuit is what I thik it is, the cap filtering the B+ input to the flyback will increase horizontal scan if the ESR goes high, and it also has intermittent immediate shutdown at startup. And it needs the 220 volt capo as well because it has jailbars, but that doesn't affect the scanning.   I think I got the caps laying around somewhere and intend to fix it. But I am sure the little shit will still overscan. It cuts off part of the captions, which is the main problem. So I have a choice of two ways of reducing the horizontal size. I am just wondering which one is better.   One way is to reduce the regulated B+. This might be easier ssaid than done if it is not adjustable and uses one of those hybrid DM type modules to control the regulator. ButI would still do it with a staclk of Zeners and just let the DM module be the current source. The regulation wouldn't be as tight but it would be good enough. the drawbacks are that the drive to the horixzontal poutput will be decreased which may result in higher dissipation. Also the B+ to the vertical IS being scan derived will be reduced and the on time of the bottom transistor may be longer and increase the dissipation of the IC. Adjusting the vertical height will not fix this. It would have to be adjusted anyway though because the ramp amp is probably run off a sub-regulated supply. Otherwise I get that foldover at the top.   The other alternative is a bucking winding on the flyback. Usually on these I can get in between the core and coil of the flyback so I just need to wind some wire in there which would be in the same polarity as the yoke feed, but inserted in series with the yoke return line. The problem here is that it will decrease the high voltage and increase the deflection sensitivity which would be working against itself. Also the switching optimization might be compromised with a longer duration pulse there, plus that lengthens retrace time which also works against itself.   Just for shits and giggles which way you think would be better ? I'll get it done no matter, but I am just trolling for opinions. I got too much time on my hands I guess. I need some work.   So, if you got too much time on your hands and know how these ^%&*##$s work, type it up.

tabbypurr@gmail.com: Feb 09 04:54AM -0800 > I just need to wind some wire in there which would be in the same polarity as the yoke feed, but inserted in series with the yoke return line. The problem here is that it will decrease the high voltage and increase the deflection sensitivity which would be working against itself. Also the switching optimization might be compromised with a longer duration pulse there, plus that lengthens retrace time which also works against itself.   > Just for shits and giggles which way you think would be better ? I'll get it done no matter, but I am just trolling for opinions. I got too much time on my hands I guess. I need some work.   > So, if you got too much time on your hands and know how these ^%&*##$s work, type it up.   Reducing B+ reduces EHT too, which is derived from B+, so picture size doesn't change. But you get less brightness. Best option is make it work as it should.   Don't increase B+ on failing tubes, it increases xray output.     NT

John-Del <ohger1s@gmail.com>: Feb 09 04:56AM -0800 > I just need to wind some wire in there which would be in the same polarity as the yoke feed, but inserted in series with the yoke return line. The problem here is that it will decrease the high voltage and increase the deflection sensitivity which would be working against itself. Also the switching optimization might be compromised with a longer duration pulse there, plus that lengthens retrace time which also works against itself.   > Just for shits and giggles which way you think would be better ? I'll get it done no matter, but I am just trolling for opinions. I got too much time on my hands I guess. I need some work.   > So, if you got too much time on your hands and know how these ^%&*##$s work, type it up.     I wouldn't play with the B+, but maybe add a bit more capacitance across the HOT. You'd lose a little HV admittedly, but on smallish CRTs that doesn't seem to be a problem IMO.

tabbypurr@gmail.com: Feb 09 06:37AM -0800 On Friday, 9 February 2018 12:56:15 UTC, John-Del wrote:   > > Just for shits and giggles which way you think would be better ? I'll get it done no matter, but I am just trolling for opinions. I got too much time on my hands I guess. I need some work.   > > So, if you got too much time on your hands and know how these ^%&*##$s work, type it up.   > I wouldn't play with the B+, but maybe add a bit more capacitance across the HOT. You'd lose a little HV admittedly, but on smallish CRTs that doesn't seem to be a problem IMO.   I'm not clear on the details of what you're suggesting, but anything that reduces horiz scan power also reduces EHT, and vertical scan too if that runs on a LOPT derived rail.     NT

John-Del <ohger1s@gmail.com>: Feb 09 08:31AM -0800 > > I wouldn't play with the B+, but maybe add a bit more capacitance across the HOT. You'd lose a little HV admittedly, but on smallish CRTs that doesn't seem to be a problem IMO.   > I'm not clear on the details of what you're suggesting, but anything that reduces horiz scan power also reduces EHT, and vertical scan too if that runs on a LOPT derived rail.   > NT   I'm assuming he's trying to reduce horizontal overscan as vertical overscan is always adjustable and he knows that. Any modification to horiz width that causes vertical height changes can be adjusted out. By adding capacitance to the Horizontal Output Transistor (I believe you call it Line Output), the horizontal width will be affected. The HV (EHT?) will change a bit but it shouldn't be enough to cause issues.

micky <NONONOmisc07@bigfoot.com>: Feb 09 02:35AM -0500 I have a flashdrive (thumb drive) that I use to play MP3 files with music or podcasts, in the car, either by plugging straight into the car radio, or with a $15 gizmo that plugs into the cigarette lighter and broadasts in FM to the radio.   1) If I turn off the radio or gizmo or unplug the flashdrive, it starts up again either (where I left off or iirc much more likely) at the start of the song or segment I was playing when I stopped the previous time.   Where is this information stored, in the radio or the gizmo (whichever the flashdrive is plugged into)? Or in the flashdrive itself?   How is it stored? If in the flashdrive, in an identifiable file?   I could learn part of this by testing, but I'm running out of time, and I'm sure you'll have a little more to say about the topic anyhow. If it's stored in the flashdrive, I can have it keep position in more than one flashdrive, putting music on one, science podcasts on another, and history podcasts on the third.   2) There are one or two vacant FM radio frequencies, present on the radio but not used, at least in the USA. Either was a good choice for my gizmo (since my own car radio isn't new enough to play directly) but it seemed that the very low frequncy, 87.7 or 9, led to a great lack of fidelity in the sound. Was this my imagination, since 88.1 works just fine. It seems like 2 or 4 tenths of a megahertz wouldn't make much difference. (At the high end, I think 107.9 is often in use and I don't think radios go higher than that. And googling told me that the only unused ones are at the bottom.)   3) While I'm asking, my 2005 Toyota radio has a GPS on the screen, but EVERY time I turn it on, I have to touch something to agree to the legal disclaimer that show. Every time. And I don't really need GPS anyhow.   Are there newer after-market radios that either a) show GPS but don't expect me to do this every time, or b) use the screen for something else altogether, not counting controlling the radio or a rear-view camera or watching movies**???. I can't imagine what else there is, but I've known for a while that I don't have much imagination.   **I'll neve watch a movie in the car (certainly not while I'm driving), the rear-view camera is on only when I'm in reverse, and I'm sure there will be a way to control the radio. I'd rather have mechanical buttons but it's 2-din and I'd even more want to have some new-fangled gizmo.   Thanks a lot.

Andy Burns <usenet@andyburns.uk>: Feb 09 09:08AM micky wrote:   > of the song or segment I was playing when I stopped the previous time.   > Where is this information stored, in the radio or the gizmo (whichever > the flashdrive is plugged into)? Or in the flashdrive itself?   I would expect the MP3 playing gizmo stores the current track/position internally.

jurb6006@gmail.com: Feb 09 02:36AM -0800 >"I would expect the MP3 playing gizmo stores the current track/position internally. "     I would agree but I've seen CD players do it and we know of course storing that info on a CD is impossible. Well actually just too much trouble. It would have to be a CDRW and it would be a burner. Fat chance of that.   But I think it works out well if it is stored on the stick itself. That way if you change cars and take your stick of music with you the next car will just resume where you left off.   We don't want to give people other things to do while they're driving, they already have to shave, text their girl, eat breakfast and perhaps look at a spreadsheet or something for the meeting at work. Women got it even worse because they have to do their hair, nails and makeup on top of all that other shit.

jurb6006@gmail.com: Feb 09 02:39AM -0800 Wait, did you mean the stick as the gizmo or the player in the car as the gizmo ? I assumed the stick as the gizmo so take my statement accordingly.   Sometimes you have to explain that highly technical jargon.

Andy Burns <usenet@andyburns.uk>: Feb 09 03:17PM > Wait, did you mean the stick as the gizmo or the player in the car as > the gizmo ? I assumed the stick as the gizmo so take my statement > accordingly. From previous descriptions (here or elsewhere) the gizmo is a 3rd party device, the USB memory stick loaded with MP3s is plugged into the gizmo, gizmo is plugged into the car's cigar lighter and the gizmo acts like an iTrip broadcasting FM which the car's radio receives.   I suppose the gizmo could store the position on the stick rather than internally, but AFAIK there's no standard for this. My car has a built-in SD card reader rather than needing a gizmo, I don't think it ever writes to the SD card.

micky <NONONOmisc07@bigfoot.com>: Feb 09 02:00AM -0500 Increasing gauge numbers denote decreasing wire diameters, which is similar to many other non-metric gauging systems such as British Standard Wire Gauge (SWG), but unlike IEC 60228, the metric wire-size standard used in most parts of the world.     This gauge system originated in the number of drawing operations used to produce a given gauge of wire. Very fine wire (for example, 30 gauge) required more passes through the drawing dies than 0 gauge wire did. Manufacturers of wire formerly had proprietary wire gauge systems; the development of standardized wire gauges rationalized selection of wire for a particular purpose. -- Wikip   Did all know this?

thumper300zx@gmail.com: Feb 08 07:38PM -0800 > Click the Choose File button and choose any random file on your computer. I picked a small txt file. Now click the Upload button. Don't worry about what file you choose. The operation will fail, but you will have jolted the receiver out of update mode.   > You're done. BCO Update message should disappear, and life is good again!   > I hope this helps!   There is another problem, however -- if you use this method, you will permanently disable USB and from what I understand, also AirPlay (I don't have any Apple Products, so I don't really know).

Jeff Liebermann <jeffl@cruzio.com>: Feb 08 09:17AM -0800 > He has a hot air rework tool and he said I might be able to reflow >the chip. Is this something that a rank amateur can likely do? >Eric   We all have to start learning somewhere. My domain is LearnByDestroying.com which should offer a clue as to how I start learning. If you've never worked on a laptop before, your problem will not be the hot air reflow, but rather the disassembly and reassembly. Spare screws, mangled flat ribbon connectors, and broken plastic are common. I suggest you use a digital camera to record the disassembly to help with the reassembly. You might be lucky and NOT need to remove the motherboard from the case, but that's not typical. Before you blow dry your machine, you might look inside, around the lower left corner, and see if any connectors have come loose. Also, find an air compressor and blow out the dust, especially around the fan.   There are YouTube videos showing how to use a hot air gun to reflow a BGA. <https://www.youtube.com/results?search_query=hot+air+bga+reflow> Make sure you build a heat shield out of aluminum foil to prevent melting nearby plastic parts. Practice on scrap PCB's before attempting to fix the unspecified model Asus laptop. It's quite difficult to tell if the low temperature solder balls have reflowed. I'm undecided if liquid flux does anything useful.   Good luck.   -- 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

etpm@whidbey.com: Feb 08 05:37PM -0800 On Thu, 08 Feb 2018 09:17:52 -0800, Jeff Liebermann <jeffl@cruzio.com> wrote:   >difficult to tell if the low temperature solder balls have reflowed. >I'm undecided if liquid flux does anything useful.   >Good luck. Thanks for the advice Jeff. And the link. I did take this machine apart once about 5 years ago to replace the hard drive. That all went fine. Your "unspecified model ASUS" remark made me laugh because when I was typing out the original message I realized I didn't have the model number on hand and knew at the time that I really should have included it with my post. I always seem to get caught. Thanks Again, Eric

jurb6006@gmail.com: Feb 08 03:50PM -0800 This is the same scope as in the "Cheap And Easy 6.3 Volts thread.   It has mucho problems in the vertical. I found a couple of shorted transistors and wondered at first why ? The thing WAS working fine but then IT WAS ARCING ! No wonder.   So I am muddling my way through the stages running down some clipping and what was an offset in channel 2. There is a blocking oscillator that feeds a multivibrator for the channel switching. The oscillator isn't running. It was alwayts stuck in channel one. The transistor, Q260 was dead shorted all the way around. How the arc got there is, well Ithink it should have blown more shit, and it might have.   Upon the replacement of Q260 it now switches channels, in alternate. The switching is totally erratic and I haven't investigated the pulse coming from the horizontal plugin yet. (it is a 3A1, and the print is not available online) But it does something, which is more than it did before. It still doesn't oscillate so therefore it won't do chop mode. Apparently the shorted Q260 was shorting out the pulse form the horizontal but now it is passing, somewhat. The channel switching is not instigated by the horizontal pulse, it is random. It is not even frequency dependent. And of course in chop it doesn't switch at all.   There is a little transformer in that oscillator circuit, could the arcing have shorted it out ? that might explain things. the pulse is compressed, and no oscillation, that symptom is about what would happen if the transformer has a shorted winding. The other problem is finding things. Not only am I half blind, I got used to circuit boards and it is now harder for me to follow point to point wiring.   And both channels are clipping before the signal hits Q134 and Q144 as evidenced by the fact that the trace is very large at the 10 mV setting due to sections 5F and 5R of SW110, the vertical gain switch.   I have checked the power supply. All regulated voltages are tight but the unregulated voltages are low due to low line voltage. It comes up when I shut off the electric heater that is on the same extension but that has no effect on the scope, it acts the same.   There is a 3A1 on eBay for $ 10 but it is marked for parts only. I wonder how many of these scopes got the arcing transformer blues.   The first time with the original power transformer there was nothing hooked up to the vertical input. This time there was and that is probably what sent that arc through the system. Ten bucks isn't bad, but if I get the same problems, plus pay $ 19.71 in shipping it is not worth it. This is supposed to be fun, I have other scopes to use, much simpler and a bit more bandwidth. I like to play around with the dual time base. Pick some complex waveforms to pieces n shit.   I got some wrong voltages that don't really make sense, but that is typical of when things arc. I'll list them later when I put it back up. I had to set it aside for ow, but any good ideas and I'll put it back up.   In the meantime if anyone has any ideas I am all ears.

tabbypurr@gmail.com: Feb 08 03:46PM -0800 On Wednesday, 7 February 2018 17:29:49 UTC, Jeff Liebermann wrote:   > <http://store.caig.com/s.nl/it.A/id.2847/.f> > "Shields Against Noise and RFI" > Ummm... right.   What? If you sprayed it in your ear it would shield you against noise. And when were you last hassled by Robert Fred or Ian? See it does shield you from R,F&I.     NT

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