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cody and callan

How to associate windows right click to a program of your choice. Notepad or GetDiz viewer

By editing the windows registry and adding these keys and data strings you can have GetDiz or Notepad popup after a user right clicks on a file..
Do this by editing the registry with the following...


Key Called --> \HKEY_LOCAL_MACHINE\SOFTWARE\Classes\*\shell\GetDiz
String Value --> Default = Open with GetDiz Viewer
Key Called --> \HKEY_LOCAL_MACHINE\SOFTWARE\Classes\*\shell\GetDiz\command
String Value --> Default = C:\Program File\GetDiz.exe "%1"

Beam Construction

http://www.hammerzone.com/archives/framecarp/repair/porch/beam13/replace.htm

Our old house had a problem with the roof structure on one of the porches. A previous owner had replaced the load bearing beam with a smaller piece of wood, and the roof was sagging by about 1½" in the middle of the beam span. Besides being too small, their replacement beam didn't even come close to matching the architectural detail found on the other porches.
So in the midst of re-shingling that porch roof, we decided to spend a couple of days fixing the structure. This repair involved:
Supporting the weight of the roof.
Removing the old beam.
Repairing rotted framing members.
Installing a new beam made of four pieces of lumber.
Replacing the wood trim.


http://www.ilevel.com/roofs/r_ParallamPSL_beams.aspx

Multiplexer 75 ohm Terminator reduces Cable Ringing and Transmission Line Effects

http://www.eagleaspen.com/admin/download/fujian/file_27.pdf

75 ohm TERMINATORS
To minimize off-air analog ghosting or off-air
digital signal dropout, the 75 ohm terminator
(1 included) must be used on the unused
output at the Combiner, as shown, or at the
end of the unused cable. Save unused
terminator for future application.

The multiple outlets are a problem. If the terminations are not 75 ohm then reflections occur up the cable. Sometimes local oscillator signals also get back into the system. Local oscillators are in TVs, Videos, STBs.

TERMINATORS

The end of each 75 ohm distribution cable and any unused port on MATV equipment must be terminated with a 75 ohm resistor to prevent signals from traveling back up the line and causing ghosts. These resistors are called term- inators. Whenever line power is added to a system, a voltage-blocked terminator must be used.

75 Ohm Terminators are used on all signal outputs that are not con-
nected to a television or VCR. They prevent signal loss and avoid RF
leakage on unused outlet ports.



Ghost A condition that exists where an off-air antenna receives a
desired signal along with one or more identical time delayed signals,
caused by the main signal reflecting off inanimate objects such as
buildings, etc



From...
http://www.ecircuitcenter.com/Circuits/tline1/tline1.htm

Transmission Line Terminations

CIRCUIT

TLINE1.CIR Download the SPICE file

Drive a high-speed signal (digital data or video) into one end of a long coax cable and you might be surprised - at both ends of the cable! Over long distances, electric signals act more like traveling waves than instantaneous changing signals. What kind of effects can result?

In the classic analogy, a ripple travels smoothly in a pool because one volume of water has the same "impedance" as the next. However, a wall or human body, presenting a very different impedance, reflects the wave in the opposite direction.

In video signals, reflections occur in a similar manner at mismatched impedances creating distortions and ghosting. Digital signals may show slow rise times or spurious transitions through the logic threshold region. What can you do about it? Matching the electrical impedance of the cable at one or both ends can reduce reflections dramatically. But before you make a decision, you need to understand the pros and cons of each option.

LINE IMPEDANCE AND REFLECTIONS

For short rise times or high frequencies a transmission line (coax cable, twisted ribbon cable pair, PCB trace over a ground plane) displays a characteristic impedance (50 - 300 Ω), depending on its materials and physical dimensions. A signal traveling down a line will be transferred without reflection if the load impedance RL matches the line impedance Z0. If not, part of the wave is reflected. How much? A simple equation predicts the ratio of reflected Vr to incident Vi amplitude

Vr / Vi = ( RL - Z0 ) / ( RL + Z0 )

Three cases show the range of values for the reflected wave

Matched Load: RL = Z0 Vr / Vi = 0 No reflection.

Open Load: RL = ∞ Vr / Vi = +1 Full reflection, same polarity.

Shorted Load: RL = 0 Vr / Vi = -1 Full reflection, inverted polarity.

UNTERMINATED CABLE

Suppose you need to drive a video or high speed digital signal to a remote instrument or monitor over a 75 ohm cable. In the circuit above, amplifier VAMP represents your line driver with a source impedance RS = 5 Ω. At the other end of the cable (5 meters) is the input impedance of the line receiver, RIN = 10k Ω and CIN = 10 pF. The terminating resistor RL is essentially not in the circuit RL = 1MEG. Basically, the load looks like an open circuit compared to the 75 ohm cable.

CIRCUIT INSIGHT Simulate the SPICE file TLINE1.CIR. Amplifier VAMP produces a 1V voltage step with a short rise time. Plot V(2) and V(3), the voltages at both ends of the cable. How long does the rising edge take to reach the end of the cable? You should see a delay of about 20 ns.

What happened to the step voltage at the load end? What caused these unspeakable horrors to the step waveform? According to the equations above, the cause was a full positive reflection at the load! Together, the 1V (approx.) reflected wave adds to the 1V incident wave resulting in the near 2V level at the load end. Now, what happens to the reflected wave as it returns to the source VAMP. This returning wave essentially sees a short (RS = 5 Ω) and produces an inverted reflection that travels back to the load. The cycle repeats to create ringing on the line.

LOAD TERMINATION

Terminating the line correctly can remedy the situation. To make the load appear like just another segment on the transmission line, place a resistor, RL = 75 Ω, at the end of the cable. The step function should be transferred to the load without reflection.

HANDS-ON DESIGN Change RL to 75 Ω and rerun TLINE1.CIR. Check out V(2) and V(3). Is the step function preserved?

All is well (almost). You may have noticed a little blip at V(3). What causes this? Actually, the 75 Ω terminator is not really 75 Ω. There's a capacitor CIN = 10 pF shunting RL = 75 Ω causing it to be less than its expected value for short rise times. To see a blipless waveform, temporarily remove CIN by placing a * at the beginning of the CIN line. Rerun the simulation. Has the blip disappeared? Return CIN into the circuit by removing the *.

Load terminations come with a price. Plot the required amplifier current by adding trace I(RS) in a separate plot window. Notice the amplifier needs to source 12.5 mA of current for the 1 V step function!

SOURCE TERMINATION

As another termination option, place a 75 Ω resistor in series with the amplifier and leave RL open. If your amplifier's output impedance is 5 Ω, insert a 70 Ω resistor for a 75 Ω total. The waveforms get a little more interesting for a source match. But the bottom line is the same, the waveform is preserved at the load end.

HANDS-ON DESIGN Modify TLINE1.CIR for RS = 75 Ω and RL = 1MEG. Rerun a simulation and check out V(2) and V(3). Notice that the initial voltage at V(2) is 0.5 V! That's because RS = 75 Ω and Z0 = 75 Ω act like a voltage divider sending only 0.5 V down the line. But, there's help waiting at the load end. Because the load end is open, a full reflected wave occurs and the 0.5 V incident wave adds to the 0.5 V reflected wave for the total 1.0 V level. The 0.5V reflected wave travels back to the matched source getting absorbed without further reflections.

Here's an advantage of the series termination at the source end. Look at the source current by plotting I(RS) in a separate plot. The amplifier needs to supply current only during time the initial wave travels to the load and back. A disadvantage may occur if the cable is not exactly 75 Ω due to manufacturers tolerance. Change the line impedance of T1 to Z0 = 70 or 80 Ω and test drive the circuit. The signal may require a few additional reflections before settling down.

SOURCE AND LOAD TERMINATION

One of the most effective options is matching the impedance at both the source and load ends. This configuration helps minimize distortions at the load even when the terminations do not exactly match the cable impedance. However, a DC voltage divider is formed by RS = 75 Ω and RL = 75 Ω. To compensate for this reduction in signal, boost the amplifier's signal up from 1 to 2 V.

HANDS-ON DESIGN Modify TLINE1.CIR for RS = RL = Z0 = 75 Ω. Remember to crank up the drive voltage by changing VAMP's voltages to 2V. Run a simulation and check out V(2) and V(3). Does the 1V step arrive at the load as expected?

Simulate the cable manufacturer's variations by changing T1's impedance to Z0 = 70 or 80 Ω. What is the impact on the waveform at V(3)? It should be minimal.

SIMULATION NOTES

Transmission lines are defined by two parameters: characteristic impedance Z0 and delay time TD. What is the delay time? This tells you how long it takes a step voltage to travel from one end of the cable to the other. The time delay is easily determined by the cable speed and cable length. In the circuit above, the 5 meter cable is specified as having a speed of 85% compared to the speed of light. The time delay is calculated as

Time = Length / Speed = 5 m / (0.85 ∙ 300e6 m/s) = 19.6 ns.

The SPICE transmission line looks like

T1 2 0 3 0 Z0=75 TD=19.6NS

where nodes 2 0 and 3 0 are the connections at either end of this bidirectional device.

SPICE FILE

Download the file or copy this netlist into a text file with the *.cir extention.

TLINE1.CIR - TERMINATED TRANSMISSION LINE
*
* AMPLIFIER, SIGNAL RISE TIME = 10NS
VAMP 1 0 AC 1 PWL(0NS 0V  10NS 1V  300NS 1V)
*
RS 1 2 5
*
* 75 OHM COAX, 5 METERS LONG, RELATIVE VELOCITY 85%
* TD = 5 METERS / ( 0.85 * 300MEG METERS/SEC) ) = 19.6N SEC
T1 2 0 3 0 Z0=75 TD=19.6NS
*
RL 3 0 1MEG
*
* INPUT Z OF RECEIVER
RIN 3 0 10K
CIN 3 0 10PF
*
* ANALYSIS
.TRAN 1NS 300NS
*
* VIEW RESULTS
.PRINT TRAN V(2) V(3)
.PROBE
.END

Update on 6 Tennis Lessons

OK, It's been almost 6 lessons now. And I think my game strategy has changed quite a bit. Instead of hitting with power and speed like I used to, I'm now focusing on more consistency and getting the ball in play so that when the opportunity arises, I will attack the short ball or find an opportunity to go for it!.

So some key points that I've learned ...

Backhand
When setting up the shot, the footwork is key here. I should take multiple small shuffle steps and really allow foots to close in on the shots. My left foot should be the one in lead (but behind), and my right foot should follow. First plant, but loosely my left foot, and then push off the left foot and drive away from it with my body rotation. My right should clearly be rotated, or pointing the the LEFT side of the courts. Both wrists should be completely relaxed, as to promote the racquet head to be dropped down. If the wrist is firm a bit, the racquet head goes up, and when you hit contact, the ball will shoot long, or might possibly be worse, into the net. Another thing to remember is that I should never allow my right foot to cross over the left foot, this might cause my left foot to prematurely lift up, and looks ugly. I should think of hitting the tennis ball like a golf ball. Think about that to hit the ball both feet must be in-line with the trajectory with the ball. In-line will allow my shots to go straight down the line.. When my feet is not in-line but with my right foot (to the right of the left planted foot) will make the ball go cross court. If my right foot has crossed over the left foot, then this will cause me to loose balance, and I will not be prepared for the next shot coming back. An important thing to remember is that after I have swung the ball, I should not look up at where the ball is. I should keep a beat longer at where I have hit contact. Before contact, I my feet should take 2 short skip steps, and after contact btake 2 more skip steps. This will keep me balanced and ready for the next shot.

Forehand
Alrighty forehand is a bit easier. But b/c I have wrist pain. Ouch!. The only thing I need to remember is to have my right wrist relaxed, and not firm. Let the racquet head drop, and keep it like that till I have followed through on my swing. It's imporant to not follow the ball, but to be like Federer, and look at the contact point for a beat longer.

Volleying
I think I've improved a lot since taking one lesson. They key here is to make the racquet head point to the opponent, and track him. Don't allow the racquet to drop below your waist level, and always keep the racquet in front of you. Kind of like keep racquet like "I" but not resting "\" or "/". I used to always do "\", which would cause me to always have late contact on hitting. Imagine making the racquet with quiet swings, and short compact movements. Very Impt. to keep the racquet in front of you and above the waist and like "I". This will totally improve my volleying. If I want more pace or speed with the volley, I simply use my feet and push off the ground and put the ball onto the strings, which gives it pace!.

Approach Shots
Still working on this, but 2 things I should remember is that 1) when I receive a short ball I should keep eye contact on ball impact for a beat longer, after I have swung, and then I can look up. 2) Also when no time to look at the impact of ball, don't just plant the feet and not move, you gotta move your feet and move forward/follow through feet.

Approach Shot Finish.
When the ball is kind of short near the service line, instead of returning it with a loopy long shot, i should return it with like a slice or put it down the line to somewhere in service line area. If I give a deep shot, that is the returner's comfort zone and they can pass me easily. Since I put the ball kind of short, this will make the guy try to pass me or at least put the ball up so that I can easily put away the shot with a volley.

Private Tennis Lessons Goals

These are things I would like to achieve ...

1. Get to the 4.0 level by being more consistent.
2. Be fit and fast
3. Learn strategy and placement

Primary

• serve motion (correct it to make it look great like a ATP pro)
• backhand swing (from high bounce, for approach shot, like Martina Hingis)
• overheads ( my problem is that my shots go long or out, also I miss the ball for either I swing to early or don't jump)
• approach shots (to close out points at net)
• volley technique (grip, stroke, especially backhand, it seems I'm chopping the ball)

Secondary

• dropshots (like Agassi)
• swing volley (like Kim Clijsters)