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mike <ham789@netzero.net>: Feb 10 01:04AM -0800 I've got another laptop needing a nVidia chip reflow. I'm refining the technique. What's the recommended air temperature? I have heat guns with open loop variable power input. And some with thermal feedback to control the air temperature.   I'm using thermocouples on top and bottom of the board and manually controlling heaters while watching temperatures. None of the heat sources are currently set up for computer control.   I'd like to try fixed heater positions and control the heater power for better repeatability.   First thing that comes to mind is to have the air temperature track the board temperature with the difference set to get the proper temperature ramp at the chip. Then there's the relationship between air flow rate and air temperature.   That should minimize overheating. This has the potential to bloom into a local microcontroller and a computer interface and graphs and and and...   Or, am I worrying too much and should just use fixed temperature air.   What temperature air?

N_Cook <diverse@tcp.co.uk>: Feb 10 03:48PM On 10/02/2015 09:04, mike wrote:   > Or, am I worrying too much and should just use fixed temperature > air.   > What temperature air?   Can you make up a very small TC and push it into the ball grid of a scrapper and monitor with different settings of heat /airflow/ hotplate-temp ?

N_Cook <diverse@tcp.co.uk>: Feb 10 03:51PM On 10/02/2015 15:48, N_Cook wrote:   > Can you make up a very small TC and push it into the ball grid of a > scrapper and monitor with different settings of heat /airflow/ > hotplate-temp ?   totally OT, bloody thunderbird, where did the italicised "airflow" come from in my previous

rev.11d.meow@gmail.com: Feb 10 08:17AM -0800 On Tuesday, February 10, 2015 at 1:04:36 AM UTC-8, mike wrote:   > Or, am I worrying too much and should just use fixed temperature > air.   > What temperature air?     This might help.   http://www.instructables.com/id/Toaster-Oven-Reflow-Soldering-BGA/

Sjouke Burry <burrynulnulfour@ppllaanneett.nnll>: Feb 09 11:27PM +0100 On 09.02.15 13:41, N_Cook wrote: > LF353, to something low noise or some other known cause. When trying it > out, the hiss peaked for a while, then dropped back, not returning on > twizzling. Not tried heating/cooling yet   Get a scope and check for oscillation. Your symptoms describe just what you heard/saw.

N_Cook <diverse@tcp.co.uk>: Feb 10 03:47PM On 09/02/2015 22:27, Sjouke Burry wrote: >> twizzling. Not tried heating/cooling yet   > Get a scope and check for oscillation. > Your symptoms describe just what you heard/saw.   Nasty short bursts of high power did not show any spurious ringing or unwanted oscillation of the Hi-amp anyway. Crude visual pk-pk of noise on scope was about 80mV on 8R load on hi-amp output with shorted input and main volume at max and Hi-Master volume at max, other controls at mid. Warming U1 ic,localised, to about 80-100 deg C made the noise level jump to about 200mV . Squirting freezer spray could make a minimum of 50mV but would then jump up and down abruptly between about 80 and 150mV, between discrete levels, which is probably what was most intrusive in use proper, the hiss varying in level. Localised heating of the other ICs nothing observable on scope. So out with U1. What did we use before freezer spray?, I suppose alcohol on a cotton ball and blowing breath through a straw.

Jeroni Paul <JERONI.PAUL@terra.es>: Feb 09 12:49PM -0800 In SD the stream has a 4:3 16:9 indicator that should be used instead of adding side bars into the picture. This has two advantages: first the full available resolution is used for useful video content and second the decoder makes the best fit in whatever screen size the video is being played with the possibility to be configured.   It is common nowadays to see 4:3 programs broadcast in 16:9 with side blackbars, I hate it, it makes an inefficient use of the available resources and looks really ugly in a 4:3 display.

anonymous@myhome.com: Feb 09 04:39PM -0600 On Mon, 2 Feb 2015 05:52:02 -0800 (PST), Tim R <timothy42b@aol.com> wrote:     >It's not clear to me if that circuit shows before the amplifier or after.   >If not, is there a better way to do this? Or better just not to do it at all?   >thanks,   Why not just go to Goodwill or on Craigslist and buy another speaker. Even if it dont match, it seems you just want louder sound anyhow, and you could still get an RCA adaptor to bridge the inputs so both speakers are getting both channels! Bridging outputs is dangerous for the amp. If your TV signal is coming from a headphone jack, it will probably need a dropping resistor ir it will overload the preamp on the amplifier.

rev.11d.meow@gmail.com: Feb 09 06:15PM -0800 On Monday, February 9, 2015 at 12:49:21 PM UTC-8, Jeroni Paul wrote: > In SD the stream has a 4:3 16:9 indicator that should be used instead of adding side bars into the picture. This has two advantages: first the full available resolution is used for useful video content and second the decoder makes the best fit in whatever screen size the video is being played with the possibility to be configured.   > It is common nowadays to see 4:3 programs broadcast in 16:9 with side blackbars, I hate it, it makes an inefficient use of the available resources and looks really ugly in a 4:3 display.       4:3 stretched to fill 16:9 makes everyone look fat.   "Black Bars are stealing my screen real estate," is the absolute funniest Luddite response to technology today.

rev.11d.meow@gmail.com: Feb 09 06:29PM -0800 On Wednesday, February 4, 2015 at 11:58:44 AM UTC-8, Jeroni Paul wrote: > to all this. Mixing the two channels with a Y cord may produce a faint > or no sound if wide stereo techniques are applied in the broadcast. > I find that using only the left channel is safer.     How do you Broadcast "Wide Stereo" AND "Mono Capable" at the same time?     I'm pretty sure "Wide Stereo" is something that happens in the Receiver, not the Transmitter.   My mileage may vary...

vjp2.at@at.BioStrategist.dot.dot.com: Feb 09 07:07PM WHat is it called when you sometimes prematurely hangup and the phone system automatically calls you back and tries to reconnect you with the number you called?   I've had a bizarre behavior with dialup modem where somehow a call from outside manages to derail my dialup and ring my phone. Perhaps is it some aggrssive robocalling technique, but I suspect it was bad weather distrubing my connection and then trying to call me back?   I still haven't observed this carefully enough to figure out what happens.         - = - Vasos Panagiotopoulos, Columbia'81+, Reagan, Mozart, Pindus, BioStrategist http://www.panix.com/~vjp2/vasos.htm ---{Nothing herein constitutes advice. Everything fully disclaimed.}--- [Homeland Security means private firearms not lazy obstructive guards] [Urb sprawl confounds terror] [Phooey on GUI: Windows for subprime Bimbos]

jurb6006@gmail.com: Feb 09 11:35AM -0800 Not sure exactly what you're asking here.   I do know this, when on a dialup with call waiting, ass *70, before the number it dials. Yes, include the comma. Sometimes you don't need the coma, sometimes you do. All it does is tells the MODEM to pause. That gives the system time to issues the second dial tone. Sometimes it doesn't matter, but if you are still on dialup for all I know you could be in East Jabbaba somewhere with a 100 year old phone system. I see DSL in the US ffor like twenty bucks a month. Actually if you can get it without the phone service you couldd just geet a ?Magicjack for the phone hich is something like twenty bucks a year.   Oh, old phone systems, if, on the really off change you have call waiting but not tone dialing it is 1170 instead of *70, though 1170 should also work on tome dialing.   Now to stop the telemarketer you need what's called "sit tones.wav" which are the tones you hear when you dial a nuber not in service. Record that on your answering machine before you outgoing message. Then the computer at most telemarker's should pull your number from the list.

rev.11d.meow@gmail.com: Feb 09 06:11PM -0800 > I do know this, when on a dialup with call waiting, ass *70, before the number it dials. Yes, include the comma. Sometimes you don't need the coma, sometimes you do. All it does is tells the MODEM to pause. That gives the system time to issues the second dial tone. Sometimes it doesn't matter, but if you are still on dialup for all I know you could be in East Jabbaba somewhere with a 100 year old phone system. I see DSL in the US ffor like twenty bucks a month. Actually if you can get it without the phone service you couldd just geet a ?Magicjack for the phone hich is something like twenty bucks a year.   > Oh, old phone systems, if, on the really off change you have call waiting but not tone dialing it is 1170 instead of *70, though 1170 should also work on tome dialing.   > Now to stop the telemarketer you need what's called "sit tones.wav" which are the tones you hear when you dial a nuber not in service. Record that on your answering machine before you outgoing message. Then the computer at most telemarker's should pull your number from the list.       *70 doesn't tell the modem anything. It tells the telco switch to disable Call Waiting for the one call. It is the Call Waiting tone that is derailing your modem's call, sometimes not.

N_Cook <diverse@tcp.co.uk>: Feb 09 08:12PM And a second query answered   Is there any long term degradation problems with LC. If you have a TV display or an instrumental 7 segment display , it requires a certain amount of voltage for a certain amount of contrast. If the voltage step stays the same , 20 years time, will it produce the same contrast?   You do get a degradation. Known as image sticking . Its not actually LC fault . We like to think that we've only put molecules in there that we want , but we process them in a factory , transpported , stored them and we introduce impurities. Some of these impurities are going to be charged within the LC. I apply a voltage so a positive voltage over here and negative over there that attacts charged material to either side. Bits of rubbish here and bits of rubbish there . Generally if you turn it off it will all relax back intio the system and no problem except for something called charge-screening?. However you have a polymer on the surface and you can get a chemical interaction wiht the rubbish and stay s locked in when turned off, that contributes to inmage-sticking. So switched off there is still an electric field . Especially in the early days , if I displayed a still picture and leave it on for just 3 or 4 hours then the image will stay there even when turned off.

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