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1
General Chat / Re: Apple & Customs STOLE Louis Rossmann batteries
« Last post by zucca on Today at 12:12:03 am »
It is my laptop, I paid and now it's 100% mine. I just want to fix my stuff.
If I found someone who can sell me replacement parts for my laptop, why I can't buy from him?

If they are bad parts, bad for me not for Apple.
If they are good parts, good for me not for Apple.

If after Louis doing the job the laptop will have or has some problem I will knock Louis's doors not Apple one.

We have enough problem in this life, why are we making our life even more complicated?

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Show us your code for the keypad MCP23008's initialisation and AN1081 based key interrupt, key scanning and key release detection.  There's probably something hinky in the initialisation, or how you are reconfiguring the MCP23008 after the key interrupt.

Also, how is the MCP23008 INT pin connected to the Arduino, and what have you doen with the MCP23008's reset pin?
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In theory you could get some of that hair thin steel wire and weave it trough the thing in more unconscious spots. But i think unless your bare skin touches it it wouldn't help since the material would still charge up.

I guess one thing you can try is getting a air humidifier. High air humidity tends to stop static because it causes most materials to leak charge.
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Microcontrollers & FPGAs / Re: Alternatives to Newlib-Nano?
« Last post by technix on Today at 12:03:48 am »
Speaking as a compiler vendor who has multi-thousands of users since 1994 for MCU from HC11, HC08, CPU12, ARM V7, Propeller, MSP430, Cortex... we have always used a single core printf-format function and use function pointers to either write using putc, or stuff the output to a buffer, depending on whether it is printf or sprintf (and the variants).

Indeed, for the smaller MCUs, it's a worse sin to have multiple similar code functions than printf being slow as customers can easily understand that printf can be and will be slow, due to its features.
I had the misfortune of having to work with some folks that really loves to use printf, and they need a fast implementation of printf with a limited memory space.
5
Hey there,

If under the same lighting conditions (No shadows on solar cells), one possibility is that the switching buck converter makes the solar efficiency down. My suggestion is to have a solar controller to make it suitable for your e-load.

This Hovall solar phone charger is good for all USB devices and laptops.
https://www.hovall.com/product/solar-phone-charger/

Paul
6
Ok, dumb thread time. We have an annoying situation and I'm looking for creative solutions:

We have a rather nice sofa, but it has the really nasty habit of building up electrostatic charge on anything that gets in contact with. Doesn't matter what you wear, even cotton. The charge build-up is actually quite significant. Sometimes the discharge voltage feels pretty similar to a piezzoelectric igniter spark zapping you. I've seen arcs 5 mm long. It's the worst ESD I've seen for any furniture for a long time. The upholstery fabric is like one of those micro fibre things... looks nice... doesn't play nice. Wooden floor. Couch is in the centre of the living room.

My GF and I accidentally shock each other routinely in various ways... I tell you what, it turns the cliche "electric kiss" into a literal experience. I can deal with the shocks fine, after years of fooling around with step-up transformers, but the experience can bring her to tears. I'm also concerned about touching equipment, like laptops, or hifi equipment. They are all grounded, but I fear ESD damage if I happen to touch a port pin, or an audio input for a preamp.

Antistatic sprays work for a week, but it's back to square one after that. Re-upholstering is out of the question, as the couch is relatively new. The large cushion covers could be replaced, but then it won't match the sofa material, so I try to avoid that. Anyone know of a good conductive lining/material I could put inside the covers? What else could I do? Crazy ideas welcome.

7
Repair / The Sears Silvertone Twin Twelve 1484 Major Restoration Project
« Last post by jcrubin on Yesterday at 11:56:32 pm »
Chris called me up from Cornerstone music with an amplifier in such disrepair that he was giving it to me for free.  I have a sneaking suspicion he took hard to see pictures in the text messages for fear I might not show up to pick up the amp.  What I saw was horrible.   I have a good feeling that this was out in the weather for a while or at best in a wet basement for a great many years exposed to the elements.   I have decided that regardless of all of this, the Silvertone would be my yearly Shango66 resurrection challenge, along with full restoration.

     There will be as much electronics work as body work and vice versa.  This thing is absolutely horrible. I feel disgusted to touch it.  layers of crap are coating this thing.

     Tubes falling out.   Wires cut, chewed up by rats, the inside just covered in god knows what.  Oh boy.  So ill just remove the tubes and get this amp out of the cabinet.   Surprisingly the underside of the amp looks really nice except for the caps that seems to have formed a film upon them. 

     After blowing out the cabinet, chassis cleaning starts, and that means scrubbing, because its disgusting.   and aluminum does clean up ok.   The challenge comes in starting to pull the rust out of the front face.  Its a cheap chrome plating on metal with silkscreen.  I need to go deep enough to remove the rust, but I also need to grain it to cover the imperfections.   All of which needs to be balanced to not remove any paint.   The metal work went really slow.

     Slowly work is being done on the amp cabinet to pill the dirt out of the grain as well, I keep going back and forth between the two as I start comprehensive polishing of the chassis.  The electrolytic cap will not be used anymore so it will be left in place and shined.   The reverb tank will have to be removed and restored separately.

     After the final cleaning of the chassis its brought outside for the final blowout also allowing for bench decontamination.  This begins the next phase, starting with the replacement of the fuse holder for the amp.  Following this, the Power transformer is removed from the chassis, remembering where everything was connected to.  Also the covers of the power transformers, exposing more places to clean.

    I tool this time to check out the works cheapest reverb tank. and shine up the aluminum for it, i put it to the side so I could make a test for it later.   What I really want to do it test that power transformer with the impedance bridge.

     Testing showed that I almost made it out of testing without issue, sure enough we have a serious problem with this power transformer, an open!!! and its the filament voltages.

Tune in for PART 2


8
Im not convinced the USA has loads of engineers in all sectors…when I worked on the electric drives for UKs latest electric military  ships (by Alstom Marine and offshore, called “Converteam” in UK)…..we had a  large ,  dry land test facility set up by the French in Lutterworth , Leicestershire.  It was needed because it was the most high power density electric drive in the world.   I  know that  the Americans came over and exactly duplicated the  whole thing, and built an exact replica in the States…..so it sounds to me like the USA is a bit short of electric drive engineers
If there's a working system, without serious flaws, and the world needs only a handful of them, you copy the working solution. The only sane reasons for not copying are that you are blocked from copying, or you have such a bizarre oversupply of engineers, that you can't lay off, that you might as well put them to use building a solution from scratch.

This is why the British auto industry, & to a large extent, their Electronics industry "went down the gurgler".

For instance, Joseph Lucas ("the Prince of  Darkness") could see that Bosch made better, more reliable auto electrical systems than they did, (or maybe they didn't---the illusion of "British & best" cast a long shadow),  but didn't do the most obvious thing---- get some Bosch bits, tear them down, & find out what they were doing to make them more reliable.

Another case, in the design of TV transmitters, PYE made a very ambitious 25kW UHF transmitter, of which we had two.
These delighted in killing their HT rectifiers.
The rectifiers were  tiny units which must have been adequate "on paper", but in practice, on the other side of the world, they were not.

When we started using up the spares, we frantically ordered more, but PYE were extremely "laid back" in their attitude to delivery times.----- several weeks to a month!
We got out of trouble by borrowing from other stations with the same transmitters.
NEC used massive rectifiers that usually outlasted the transmitters.

Another delight was the antenna changeover switch which enabled one transmitter to maintain the service if the other died ( they normally used both).
We spent an inordinate amount of time repairing these, (& became very familiar with the smell of burnt Teflon).
Ultimately, they were replaced with much superior switches made by Andrews.
Again, a possibly good product ruined by poor design in key points.

I mentioned long delivery times for parts.
Later, when I worked at a Commercial TV Studio, I was the unlucky sod who looked after Picture Monitors, as well as being the Transmitter person
Not the Brits this time, but the same sort of story.

We had some Tektronix 650series monitors, & they were one of that companies' rare failures.
The less said the better.

We also had some oldish Bosch monitors, which were reasonable, but "too smart for their own good",
having hinges to fold out the PCBs for service, which also served as the inter board connections.
A bit prone to failure.

As well, we had Sony monitors---- reliable, easy to work on, full documentation provided, parts available from Sony Aust, usually by next airfreight, or if they didn't have it, the day after from Singapore, who also held a large stock.

Then there were the Barcos !
"So-so" reliability, poor UI, hard to work on, very poor documentation.
If you looked at the PCBs, they were a thing of beauty, everything lined up straight as a die---lovely!
Compared to a Sony, the latter looked like crap- capacitor & resistors leaning at odd angles, ribbon cables higgledy piggledy everywhere.

The thing is, the Sony would still be going 20 years down the track, when the Barco  had succumbed to age & infirmity.
They did what mattered right!

And parts!
If a Barco failed  & you needed non-generic parts, you wouldn't expect to see them for 2 or3 months.
It seems to me that European firms wait until they can fill up a container before shipping it by sea.
(No airfreight for them).

PS:- I'm now expecting hate mail from ex Joseph Lucas, PYE, & Barco employees. ;D
Could you point out which part of that was intended as a response to what I wrote? I'm genuinely puzzled.
9
Buy/Sell/Wanted / Re: FS:SignalHound BB60C Spectrum Analyzer brand new open box
« Last post by nrxnrx on Yesterday at 11:52:18 pm »
Why did Jack03 get banned from this forum? I am currently in a transaction with him (awaiting receipt of shipment of Signal Hound BB60C).
Thank you

https://www.facebook.com/AatonDigital/posts/2077777375830303 :
Quote
Take care...
Some people offer through Facebook or Internet some CantarX3 or CantarMini new and available for sale at a good price. They indicate a serial number for the products. They ask for a deposit of 2 to 4000 Euros and payment at shipping. Take especially care about seven.cosmic(at)yandex.com or Benedetto Andreotti.
We are not related to such offers Please always contact us to check, the offers are fake - it is a fraud.

..I assume. I saw this in another of Jack03's threads (now gone, it seems).
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The test boards are to arrive Wednesday, afternoon. That's just 12 days, to have it produced, by Seeed and delivered, by DHL.

I have also been working on a Two-MOSFET design. What are everyone's thoughts on it? Particularly, the board layout...

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