EEVblog #893 - Mailbag

[EEVblog]

More Mailbag Monday



SPOILERS:
Infinity PV organic printed solar cells:
http://www.infinitypv.com/
Panasonic 840 JE-840U calculator teardown
LED controller car computer thingo teardown
Old school parallel port software protection dongle teardown
World's first logic IC! The Fairchild µL900 series, as used in the Apollo guidance computer.
Dave is taken to task about his religious rant in a previous video. Can he destroy Dave with a logical argument?
Expert witness court case letter.
Cheap ebay soldering iron of death teardown
Cheap BEC brand voltage regulator for model airplanes, is it any good? Will it meet it's claims?
Silego GreenPAK Dual-Supply Programmable Mixed Signal Matrix
http://www.silego.com.cn/web/uploads/Products/product_442/SLG46532_DS_r100_03222016.pdf

[Carl_Smith]

Back in the late 1990's my employer at the time used PCAD Master Designer (for DOS) for circuit board layout.  It used the Rainbow Sentinel parallel dongle for license control.  It has two connectors because you were supposed to be able to plug your parallel port printer into the dongle and it wouldn't interfere with normal printer operation.  But we had issues with that.

PCAD eventually came out with a Windows version around 2000 or so which lasted a few years until they were bought by Altium and everyone was supposed to migrate to Altium, but the company I worked for went under before they got that far.

[nwvlab]

Glad to see Dave having the same organic PV modules on which we are performing reliability tests

[SeanB]

Got the older version of that dongle. Has a small ATMEL 8 pin micro on it, and an A9323MAV 20 pin which I assume is either a bus switch or a buffer, plus a few odd support components. Was used to verify that a certain logging program was legitimate. too bad that it was not used by the supplier according to the OEM terms.......

With the LH0033 you really want to look for the older Nat Semi databooks, which had a lot more appropriate name for them. I think the appnote as well had the naming.  Still have a few around, they were surplus parts........

[rolycat]

Dave,

Mattia's analogy is undoubtedly flawed, but so is your logic.

The fact that many religions are mutually incompatible has no bearing on whether one of them could be correct. I would agree that it is more probable that none of them is correct, based on other evidence (or lack of evidence), but that is an entirely separate argument.

In your rant you claim (of religions)

...at best only one of them is true but because they contradict each other and that alone is in effect evidence that they are actually all made up.

This is simply wrong.

Let me attempt a simpler analogy. Suppose that rumours are circulating about a buried chest somewhere on an uncharted island. One group believes it contains a heap of gold, another that it contains a set of flawless jewels. Is the fact that they contradict each other alone evidence that the chest is really empty (or doesn't exist)?

[LazyJack]

That BEC. The output voltage is fixed. Don't calculate the power by multiplying the input voltage with the output current.

[iamdarkyoshi]

That BEC. The output voltage is fixed. Don't calculate the power by multiplying the input voltage with the output current.

I commented on that in the youtube/google- comments

[EEVblog]

Glad to see Dave having the same organic PV modules on which we are performing reliability tests

Are they any good?
What's your app?

[EEVblog]

Dave, Mattia's analogy is undoubtedly flawed, but so is your logic.
The fact that many religions are mutually incompatible has no bearing on whether one of them could be correct. I would agree that it is more probable that none of them is correct, based on other evidence (or lack of evidence), but that is an entirely separate argument.

That was entirely my argument.

Let me attempt a simpler analogy. Suppose that rumours are circulating about a buried chest somewhere on an uncharted island. One group believes it contains a heap of gold, another that it contains a set of flawless jewels. Is the fact that they contradict each other alone evidence that the chest is really empty (or doesn't exist)?

It makes the story more likely to be made up.

[Jr460]

Sorry but that "micro circuit" is not what was used in the Apollo AGC.

First two versions of AGC existed the block I and the block II.  The block II was a lot more that just made with different chips, they made some changes to the hardware as they found out things they needed/missed in the early specs.  The block I did fly, just not on any maned missions.

The first problem with that package that was sent in was both the block I and block II machines were made with 3 input NOR gates, not 2 input gates.  We look at it now and think that was stupid, but in fact it was a great idea for the time.  One part.  Fairchild could ramp up production, tweak the process and get the MTBF way down.  Check some of the documents on the net, there are graphs and charts of failure rates of the 3 input NOR gates.

The block I chips were also a single gate per package, thus it took 4100 chips in a TO style case.

The block II on the other hand went to flat pack dual 3 input NOR gate, and took 2800 of those.

A few other things that need to be corrected, it was not 16bit machine, it was 15bit, but memory had a 16th parity bit.

Memory layout was strange because the code and variable store kept growing and you only had so many bits in the the instruction for addresses.  They had to do banking and add registers that controlled banks.  Even that wasn't enough and they added a bit in one output channel for a "super bank".

The other odd thing about the machine was it's math, it was one's compliment rather than two's.  This made for a few odd things like a positive and negative zero.  Fine for most stuff but not when the hardware bumps up or down counter in memory each time a gyro sends a pulse.  It think I saw some paper from one of designers that looking back the ones's compliment was a poor design choice.

[EEVblog]

That BEC. The output voltage is fixed. Don't calculate the power by multiplying the input voltage with the output current.

Yes, I know, completely wrong. Can't edit the video now, can only do a new one.

[Someone]

Casual racism, not funny.

[bitseeker]

Using a good ol' manual typewriter:

When the keyboard has no key for the digit '1', you're supposed to use lowercase 'L' in lieu of the digit, not capital 'I'.

e.g., for the number 15

    l5 rather than I5

(Yep, I had a portable manual typewriter back in the day.)

[Smokey]

NMB is a really good fan company.  Just saying.

[Fungus]

I used those dongles back in the day.

The way they worked was that you sent it a number and it encrypted it using an on-board key then sent it back. The idea was to send it several different random numbers and make sure all the responses were correct.

This means the response was different every time so you can't just sniff the bus and make something to fake it. You need the on-board key.

PS: Re "expert witness" request letters. Why not write back and say your fees are $80,000 (or whatever)? You never know. 

[daqq]

Regarding the dongles: USB software protection dongles still exist. They aren't exactly common (fortunately) but they do exist.

[Fungus]

Let me attempt a simpler analogy. Suppose that rumours are circulating about a buried chest somewhere on an uncharted island. One group believes it contains a heap of gold, another that it contains a set of flawless jewels. Is the fact that they contradict each other alone evidence that the chest is really empty (or doesn't exist)?

Such a big discrepancy means the original source was unreliable, ie. both of them are less likely to be true as a result of that discrepancy.

(and if there was another version that claimed it was full of pearls it makes all three less likely to be correct).

[elgonzo]

What kind of logic are we talking about here right now? Something like predicate logic or (modal) probabilty logic; or perhaps just wishy-washy human logic? 

It's pretty clear that Mattia's argument is based on predicate logic, whereas Dave's argument is rooted in probability logic.
(Imo, applying predicate logic is not really useful when dealing with questions/problems where uncertainties/probabilities are involved...)

[rrinker]

 About those dongles - DOS software was often stupidly simple in how it checked those dongles. Back in the day, I had to go to a class to learn CadKey, a 3D CAD program (before AutoCAD had integrated 3D - this was better than the equivalent AutoCAD at the time) in order to support our drafting department. It used one of those parallel port dongles for protection. I had a copy of the software on my home computer, and by running it through a debugger I was able to see when it made the DOS call to the parallel port. The routine did some simple checksum testing to validate it was plugged in, but rather than much with that, I was able to get the program to run by simply bypassing the call to the "verify dongle" routine. Yes, that stupidly simple.
 The few times those more modern USB ones show up, it's usually a problem because people are using application and/or desktop virtualization and those keys just don't work with the most common content delivery systems.

[bitseeker]

@rrinker: Yep, I remember those days. Just nop the call(s) and you were home free.

[German_EE]

I have been an expert witness a couple of times and it proved to be a useful source of income. The first case was appearing on behalf of a microwave oven manufacturer where the owner had done something stupid (that wasn't listed in the manual) and then sued the manufacturer. They lost because the judge and jury decided to use some common sense. The second case was appearing on behalf of my ex employer where somebody had been involved in an elevator accident.

In both cases I was paid for every minute that I spent working on the cases including time doing research, plus, after the first case ended, there was a retainer just in case the matter went to appeal. The secret is to work out how much you were paid in your last job per hour, double that rate, and look the lawyers straight in the eye when they ask you how much you will charge.

[bitseeker]

They lost because the judge and jury decided to use some common sense.

That's refreshing. Common sense just isn't so common in real life.

The secret is to work out how much you were paid in your last job per hour, double that rate, and look the lawyers straight in the eye when they ask you how much you will charge.

That's reasonable. As an independent, you have to factor in costs that your employer would otherwise cover (supplies, utilities, insurance, taxes, etc.).

[VinzC]

And for the reference

Toto, I've a feeling we're not in Kansas anymore

• , around 1981
• , 1939

I honestly thought it was a reference to the former — I have that album, it's absolutely fan-frickin'-tastic! — until I looked up on the internet and found the excerpt from Wizard of Oz . I'd bet Dave would love to tear down the enormous Serge Synthesizer shown in the leaflet.

[EEVblog]

Casual racism, not funny.

What are you talking about?
Are you saying I said something racist?

[Someone]

Casual racism, not funny.

What are you talking about?
Are you saying I said something racist?

New Zealand is a country and race too, but you don't see the problem there. Australian courts have found such "jokes" to constitute defamation of individuals:
http://www.abc.net.au/mediawatch/transcripts/s3960474.htm
So its walking a fine line. Try making such jokes about any other nation or race.