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Comment Just got a several boxes of failed attempts... (Score 2) 298

Had a friend who is quite bright, but inexperienced with root cause elimination. 6 months ago, he went down the path of "building" his own home theatre/PC gaming rig. After several rounds of buying what the online rags suggested as the best bang for the buck, he had three collections of incompatible parts and not one working PC.

I'd done him a couple of favors in the past and he was emotionally defeated with the whole project. He ended up giving me the whole lot. The one thing all his platforms had in common was Gigabyte motherboards with a high density buzz words on the spec sheet and rave online reviews. I've not yet diagnosed all the problems, but I now have a heck of a HPC system after swagging the Gigabyte board for a ASRock that actually retails for 40% less. Turns out that dual bios feature of Gigabyte boards, is REALLY flaky.

At the end of the day, unless you are ready to learn troubleshooting skills related to the tasks, you probably ought to buy something you can box up and ship back if it doesn't work.

Comment Re:Many a young engineer.... (Score 1) 106

ALL the charge carriers are ions - atoms or molecular groups with an unequal electron and proton count, and thus a net charge - which may be either positive or negative (and you're usually working wit a mix of both).

Yes, you can argue that hole propagation is actually electron movement. But holes act like a coherent physical entity in SO many ways that it's easier to treat them as charge carriers in their own right, with their own properties, than to drill down to the electron hops that underlie them

For me the big tell is that they participate in the Hall Effect just as if they were a positive charge carrier being deflected by a magnetic field.

Thank you for the well thought out and logically coherent description of the underlying behaviors at play.

The "hole" flow as typically dumped on the unsuspecting student of semiconductors, really doesn't mesh well when mated to the metal conductors that source and sink the current flow to them. As mentioned previously, my mental model of semiconductors and the like is a fireman's water brigade, were either the majority of the line has buckets or empty hands.

For the line where there is but one set of empty hands (no bucket), the distant observer would see that "hole" flowing back to the source. For the bucket brigade line with one bucket in motion, the observer would see the flow as going to the sink/destination. In either case the motion of the water, (or the electron) is exactly the same - only the perception of the charge carriers change. The difference being whether or not the majority of carriers are "depleted" or not.

I'm keenly interested in finding more material to read up on the observed Hall effect measurements. Thanks again for your contribution to the discussion.

Comment Re:Many a young engineer.... (Score 1) 106

I didn't get hole flow/electron flow thing till I pictured it as a fireman's water bucket brigade operating in one of two modes and as observed from a 3rd party vantage point.

Imagine a single water well, and two fire brigades extending off in opposite directions. One bucket brigade has a bucket for every person on the line except one. The other has but a single bucket. They are both moving water from the well to their corresponding fires, but to the third party observer, he sees a bucket moving in the "right" direction (towards the fire), and in the other line, he sees a single "bucket hole" moving towards the well.

With few exceptions, most current flow tends to be electron flow. Following the bucket brigade analogy, "P" and "N" type doping determines if most "charge carriers" have buckets or empty hands...

Of course, I don't know for sure, but this model tends to work very well for me and well, I've never actually seen it in real life.

Comment Re:Many a young engineer.... (Score 1) 106

Reminds me of the negative vs positive logic arguments as DTL and RTL gave way to TTL (along with specialty, high speed ECL, which retained 'negative' logic).

While it is true that a "charge" migration can be instrumented and measured as being either positive or negative, the only physical thing that moves is an electron. Nothing else, and by the way - there is no "ether" that fills the void either.

This all reinforces my point that there is at least some benefit from learning how to troubleshooting a pentode based amplifier.

Comment Re:Many a young engineer.... (Score 1) 106

If there is no continuous electron flow, there is no continuous hole flow. From the first sub-nanosecond a circuit is completed, it is not a "conceptual" hole that moves, but an electron. There is an appearance of hole migration across molecules, but such an analogy could claim that the valley of a tidal wave is what wipes out coastal villages, when in fact, the valley is the artifact of the crest.

Perhaps you can point to the hole flow in an electron tube>

Comment Re:Bitcoin's move to the mainstream is being cut o (Score 1) 52

Today's payment market has three primary entities. Bank, processor, and issuer. Visa and MasterCard are only issuers and rely upon their network to coerce banks and processors to play along. AMEX is 'mostly' vertically integrated combining all three and therefore has had a higher relative value for marketing purposes (because they see and handle every part of every transaction)

Companies like Square have come in and are disrupting POS with their own network that aggregates and does bulk transactions with the issuer, but to this day nearly all consumer POS transactions are still controlled by a (very small) hand full of issuers and their networks. They have no net interest in migrating to any other form of payment or transaction, "Progress" is not in their best interest.

If this outfit can wedge themselves in and start building out a block-chain based network and eventually gain a foothold in the point-of-sale space (the last 1/4 mile in the consumer communications business), they have a chance to force a paradigm shift. A chance.

But like I said, in the long term, Bitcoin is dead at the starting gate for all but the early speculators. The ideal case, would only use the blockchain with a virtual issuer to ensure secure, very low cost transactions that are denominated in a real currency.

Comment Re:Commercially significant but 2nd fiddle to TTL (Score 4, Insightful) 60

Similar story on this end. I learned all kinds of electronics as teenager and then went off, first working on Air Force Radar for a number of years and then transitioning to software engineering as a civilian. A couple of years ago, I got my highly coveted treasure trove of TTL parts trays from my dad. Started playing around again on the same old breadboards, discovered SparkFun, EBay, and rediscovered Jameco.

Seems nobody personally knows much of anything about the 4004 anymore, but Don Lancaster's TTL cookbook is just as applicable today as it was 30 years ago.

Comment Commercially significant but 2nd fiddle to TTL (Score 5, Insightful) 60

I was one of those kids who built up simple bread board computers using stock standard TTL parts. I learned more about digital machinery in reading about and figuring out how processors work by trying to create my own bits of programmable/sequence-able logic using the astonishingly complete range of commodity TTL parts that where cheaply available in the late 1970s and 1980s.

The 4004 was an important inspiration, but TTL is what launched our pervasive digital age.

Unlike the 4004, it blows my mind how much of the original TTL part library is STILL available.

Comment Re:plex (Score 1) 236

Pretty much the same here...

Running Plex on FreeBSD 10 with 24 TB of ZFS goodness. I use PlayOn for internet video "caching" and there's a Roku attached to every TV. NoWhereMan's private Roku Channel picks up all the local broadcast I'm interested in as well.

Comment The federation needs to be united. (Score 1) 93

As both Star Trek Continues and Star Trek Phase II are fan funded, it's hugely unfortunate that they can't seem fit to combine forces and up the quality in a single concerted effort. I have a personal preference for what Vic has done with Star Trek Continues, but see merit in what Cowley is doing with Phase II. Its unfortunate that the federation remains divided.

Comment HP-RGS: better than RDP/VNC & simpler than KVM (Score 4, Interesting) 128

I spent about 6 months working on this product last year:

HP's RGS is really excellent remote graphics solution, suitable for the likes of film production studios and CAD/CAM design firms - at 4K resolutions and 30FPS video. It all sports support for a plethora of input devices from Wacom tablets to speciality LogiTech mice. To top it off, its bidirectionally compatible with Windows and Linux and Mac can be coaxed into working as well.

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