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  $45us/pc H.I.D Conversion Kit         


Author: paytonluo
Date: Jan 31, 2008 23:40

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Bulb态HID Ballast.

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no comments
  OT: 10 megajoule Rail gun         


Author: Martin Riddle
Date: Jan 31, 2008 18:58

34 Comments
  Calculating energy dissipation in a 3 phase motor/generator         


Author: Scott Ronald
Date: Jan 31, 2008 18:47

Hi

I am some code to monitor a small 3 phase generator, and I was wondering
about how to calculate the total energy dissipation. So far I have a
routine to calculate the RMS current in one of the 3 wires coming out of
the generator. I now need the resistance of the phase. I know that the
resistance between any pair of the 3 wires is 15 ohms. Is
RMS_current*15ohms the correct value to use to calculate power?

Once I have the power I was thinking I would accumulate the power
readings into a variable periodically then, once I have finished x
periods, multiply accumulated power by the total elapsed time to get
dissipated energy. I can then look at my last few energy calculations
and find if I need to slow down or turn off the generator. I need to do
this to prevent over-heating in the generator.

Scott
no comments
  Pro 82 Scanner programming cable         


Author: Scott
Date: Jan 31, 2008 17:58

I tried to locate a Pro 82 Scanner programming cable without luck so
I'm going to make a bunch of them, email me if interested
scott93727@aol.com
no comments
  Low cost SMA limiters anywhere?         


Author: Joerg
Date: Jan 31, 2008 17:49

Are there any low cost (<$10) barrel type limiters for SMA with
anti-parallel ordinary diodes in there? Female with nut on one side,
male sans nut on the other.

I know, I know, this ain't the proper way to do it because of
intermodulation. But it's the usual scenario. Units out in the field, a
bit late in the game, receiver inputs croaking, swapping the whole board
would be a bear. What I found at the usual RF places are costly and
fancy PIN diode limiter setups, often controllable via a DC voltage.
That's overkill in this case. I just need something that cuts hard to
about +/-700mV and can be non-linear. A BAV99 works just fine but I'd
hate to use a Tee and roach it on there.

no comments
  Clocks and baluns         


Author:
Date: Jan 31, 2008 16:36

Question for the RF-knowledgeable:
I intend to use AD9510 for clock distribution, as it has fery low additive
phase noise. My problem is, according to the datasheet performance is
degraded if input exceeds 2 V peak-to-peak, and the low jitter TCXO I am
considering has the typical either 3.3 V or 5 V output. Someone suggested
I use a 2:1 or 3:1 balun, but I'm concerned about bandwidth, since the
clock is square wave output (because the AD9510 datasheet says it needs
high slew rate on the inputs for optimal performance). I'm also not sure
how to handle transmission line effects. With a PCB track impedance is
easy to control, and I normally use series termination resistors at the
source on high speed lines to get a decent waveform, but I'm not sure what
inserting a balun will do...
Show full article (1.15Kb)
7 Comments
  Re: Today I had strange nightmare.         


Author: Rich Grise
Date: Jan 31, 2008 16:18

On Wed, 30 Jan 2008 18:57:06 -0800, D from BC wrote:
> Damn...That's just wack. :P
>
> Learn how to lucid dream.
> http://en.wikipedia.org/wiki/Lucid_dreaming
>

Did you ever wonder, when there's people you don't recognize in
your dreams, are they actually dreaming you? Say, there's a
crowd at the mall - are those other people dreaming their roles
in this scenario, and see me as one of the characters in _their_
dream?

I wonder how you'd test that.

Cheers!
Rich
2 Comments
  Re: Opening Black's Box, Rethinking Feedback's Myth of Origin         


Author: ehsjr
Date: Jan 31, 2008 15:06

Simon S Aysdie wrote:
> Maybe ya''ll have seen this; I thought it was interesting:
>
> http://mit.edu/6.933/www/black.pdf
>
> Also:
> http://www.cs.princeton.edu/courses/archive/fall03/cs323/links/cauer.pdf
> http://www.nap.edu/readingroom/books/biomems/sdarlington.pdf
>
> These popped up on some synthesis searches.
>
>
> "The fact that I have no remedy for all the sorrows of the world is no
> reason for my accepting yours. It simply supports the strong
> probability that yours is a fake." -- H.L. Mencken

Good stuff! Thanks for posting.

Ed
no comments
  Re: Today I had strange nightmare.         


Author: Richard Henry
Date: Jan 31, 2008 14:38

On Jan 30, 7:16Ā pm, Jim Thompson Web-Site.com> wrote:
> On Wed, 30 Jan 2008 18:57:06 -0800, D from BC
>
> comic.com> wrote:
>>Damn...That's just wack. :P
>
>>Learn how to lucid dream.
>>http://en.wikipedia.org/wiki/Lucid_dreaming
>
>>D from BC
>>British Columbia
>>Canada.
>
> If you can't orchestrate your own dreams, you just haven't tried ;-)

Some morning I wake up feeling guilty.
4 Comments
  Re: 4-pin pwm fan.         


Author: Franc Zabkar
Date: Jan 31, 2008 13:57

On Wed, 30 Jan 2008 18:04:40 -0800 (PST), ghosttwo@gmail.com put
finger to keyboard and composed:
>I've considered the speed fan route, but the machine is most likely
>going to spend most of it's time with a logon prompt, which very few
>aplications will continue to run on. It'll mainly be used for data
>entry and research. To machine itself is pseudo-departmentally owned,
>and this seems to be the most reliable technique. I considered using
>a resistor on the 12 volt line, but that would require either a three
>watt resistor, or 12 quarter watts in parallel (I can get .25W's for
>free, ...

IMHO that's not a good idea because the fan's electronics expects a
stable DC supply for the Hall sensor and possibly for the PWM circuit.

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
3 Comments
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