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Comment Re:Gutless? (Score 1) 687

The actual equation is (torque*rpm)/5252 = HP.

5252 comes from:
radians per second is (2*pi) / 60 = 0.10472 radians per second
The standard for horsepower is 550 ft. lbs / second

550 / 0.10472 = 5252

Higher RPM with the same torque curve will give you higher acceleration because the engine will pull with said torque for *longer*.

Comment Re:While we're on the subject of remotes (Score 2, Interesting) 429

Too late: (and these are just a few examples)

Interestingly, prior art to all 3 of those patents exists as many TVs and VCRs from Phillips/Magnavox had this feature built in as far back as 1993:

Sony also included it in a few TV models back in 2001.

I suspect it has not seen more widespread adoption because of battery life and penny-pinching in a cutthroat market.

Comment Re:I would tend to agree. (Score 1) 207

Unless you have a Docsis 3.0 modem, it is physically impossible for you to get 40-60Mbps. The calculation code is wrong somewhere.

Docsis 2.0 (North American annex-B) uses a single 6Mhz channel, with the highest available encoding being QAM-256 (8 bits per sample). The standardized sample rate is 5.36Msps, so *=8 gives the true peak throughput of 42.88 Mbps, of which ~38Mbps is usable data.

I see the same thing when starting a batch download with DownThemAll, which reports 6+ MBps regularly when starting, but it is simply inaccurate.

(That said, I am very happy with Comcast's "Blast" tier, which regularly gives me 20-30Mbps sustained rates as long as multiple connections are in use, like DownThemAll does. For whatever reason a single stream peaks out around 16Mbps sustained.)


Gory details on 42.88 vs ~38Mbps usable, if anyone cares:
The standard specifies Reed-Solomon FEC (Forward Error Correction), which mean 6 samples per 128 are unavailable (-4.7%). The MPEG-2 transport stream structure further has a 4 byte header per 188 bytes (-2.1%), Ethernet eats another 18/1500 (-1.2%), IP headers and Docsis map traffic account for about -3% more overhead. It all adds up to ~11%, meaning 42.88*0.89, or ~38.16Mbps -- assuming you are the only person on that downstream, because there is other per-node chatter. (EuroDOCSIS annex-A spec, btw, uses an 8-Mhz channel with 6.95Msps and correspondingly higher bandwidth.)

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