JustCom Two PC KVM Switch JC-102cpa

Found this at a garage sale.  It was still in its packaging never opened.  It was in one of those heat welded clear plastic packages that requires industrial strength tools to open.

After opening it, I discovered there were no instruction on how to operate the switch.  No owners manual. Nothing.  But thanks to the internet I found and tested the answers.

You use hotkeys to switch between computers.  You press the “Scroll Lock” key twice and then the “Up” or “Down” arrow.  (You have to do it fast.)  That switches the keyboard and the monitor, but the audio does not switch.  This sequence cycles through your attached computers.  Or if you like instead of the Up and Down arrow, you can hit “1” for computer 1 or “2” for computer 2.  With a two computer switch, it seem unnecessary.

Now for the audio, you hit “scroll lock” twice and then “F1” for computer 1 audio or “F2” for computer 2 audio.  Originally, I did not know they switched separately, but it is kind of nice cause you can keep your favorite tunes play while you switch back and forth.


Solve if u r a genius

So I saw this on LinkedIn the other day:


After guessing, I tried to find the answer online, but I could not.  Not knowing the answer really bothered me, too (arrrg!…thanks Phillip).

So after much consternation, this is want I am telling myself, so I can put this issue to rest in my mind:  It is a number system were 1 has a value of 4/121; 2 has a value of 8/121 which is 2 x 4/121; 3 has a value of 12/121 which is 3 x 4/121 and so on.

For the first equation, you have 11 x 4/121 which is 44/121. If you multiply the fraction, you have 44/121 x 44/121 = 1,936/14,641 which reduces down to 16 /121, and 16/121 is 4 x 4/121. Thus 4

For the second equation, you have 22 x 4/121 which is 88/121, so 88/121 x 88/121 = 7,744/14,641 or 64 /121 which is 16 x 4/121. Thus 16.

For the final equation, you have 33 x 4/121 which is 132/121, so 132/121 x 132/121 = 17,424/14,641 or 144 /121 which is 36 x 4/121.

So, in this number system, my answer is 36. (I could be wrong, but at least I can sleep again).

But wait…Here is a question that now plagues me, does this system have a base?


The 3D Equation of a Line Given 2 Points

First, I’ll give a quick to the point answer, then if you want more background, I give a more detailed answer below.  Note, I am not a mathematician.  I just wanted to share what worked for me. So now onto…

The quick answer:

Given Point1 (x1, y1, z1) and Point2 (x2, y2, z2) what is the line that pass through them.

y as a function of x

Equation 1:
y = [(y2-y1)/(x2-x1)](x-x1) + y1

z as a function of x

Equation 2:
z = [(z2-z1)/(x2-x1)](x-x1) + z1

If x1 = x2 you will end up with a zero in the denominator of Equation 1 and Equation 2. You will have to use Equation 3 to find z, so instead of specify x you will have to specify y.

z as a function of y

Equation 3:
z = [(z2-z1)/(y2-y1)](y-y1) + z1

Also if x1=x2 and y1=y2, you have a line in the z direction (parallel to the z axis) where the x1 plane intersections the y1 plane (or at the x1,y1 point).  So the equation of your line is simple any z point with x=x1 and y=y1.  Note, since x1=x2 and y1=y2, they are interchangeable.

The detailed answer:

Give two points in 3 dimension space what is the generalized equation of the line that passes through them.  Well, I search the web for the answer, but I could not find what I was looking for. There were vector forms and parametric forms. But what I was looking for was a formula that I could put in an x value and get the corresponding y and z values. I did find an example of a Cartesian form, but it was derived using specific points. I needed a generalized equation for two points which were unknown. My two points were going to be moving around, and the connecting line would need to move with them. So finally I derived an equation using the slope-intercept form (see Equation 4 below).

Equation 4:
y = mx+b

m = the slope of the line or rise over run
b = the intercept, point where the line crosses the y axis

My initial reasoning was since it was a line, for every x value there would be only one y or z value.  Another way to look at it…if you simply look at the xy plane, you will have a projection of a simple line onto the xy plane from that xyz line.  Once I had the y value, I could switch to looking at just the xz plane or the yz plane again dealing with a simple line.

So dealing with just the xy plane, the slope of the line (see Equation 5) is the change in y (rise) over the change in x (run).

Equation 5:
m = (y2-y1) / (x2-x1)

To find the intercept, I solved Equation 4 for b and then substituted in one on my points (x1,y1,z1). Note either point would work.

Equation 6:
b = y1 – mx1

Then I substituted Equation 6 into Equation 4 and consolidated the slope term.

Equation 7:
y=mx+(y1-mx1) = m(x-x1)+y1

Then I substituted Equation 5 into equation 7

Equation 8:
y=[(y2-y1) / (x2-x1)] (x-x1)+y1

This equation works except when x1=x2 (maybe there is a math wiz out there that knows of a work around, but I am not a math wiz. I was just trying to solve a problem). When x1=x2, then the 3D line is confined to the plane perpendicular to the x axis which intersects the x axis at x1. But within in that plane x can no longer yield information about y.  So you cannot define the line without y or z information. The equation breaks. You will get a divide by zero error (imagine part of your equation going to infinity).

The formula for z is derived in a similar fashion either as a function of x or y. For the slope and intercept, you would use the x (or y) and z coordinates. Therefore, Equation 2 and Equation 3 are derived.

Since this was an computer code experiment on my part, I used if…then statements to deal with the x1=x2 and y1=y2 conditions switching formulas as my 3D points moved through space.

Slayer Exciter Circuit Observations

A Slayer Exciter Circuit seemed like a simple exciting project to build. As a pseudo tesla coil circuit, it was low enough voltages (starting with 9 volts) that it did not seem as life threating as a real tesla coil. So I build the circuit, and here are my observations.

First, there was not any lightening like sparks coming off of the secondary coil. That was disappointing. But there were weird voltage readings midair from my multi-meter. You did not have to make physical contact with the circuit. You just had to have the multi-meter leads in proximity to the circuit.

Second, it did not light up a compact fluorescent light. Oh, well.

Third, the transistor in the circuit got hot to the touch, and you could smell it slowly cooking. Maybe something was wrong?

Fourth, my LED in the circuit never did light up. I checked and recheck the circuit, but everything was correct. Oh, well.

Lastly, when I upped the voltage by attaching a second 9 volt battery to the circuit, there was a startling POP! The transistor split in half.  Such is life.wp_20160916_19_10_11_pro

One thing that did confuse me was how the circuit switching worked. It took a lot of digging online to find an answer.  It was simple. It is based on the fact that electricity likes to take the path of least resistance. At first when the transistor circuit is OFF, the battery current flows through the 22k ohm resistor to the (B leg) base of the transistor. As soon as that happens, the transistor circuit is switched ON, and the new path of least resistance is 0 ohms through the (C leg) collector of the transistor. Since all the battery current is now running through the collector, the current at the (B leg) base goes to 0. The transistor circuit switches OFF, and the cycle repeats.

How to enter a pause for a speed dial number on a Nokia Lumia 635?

On my old phone to access my voicemail, I had a speed dial entry in my contacts list that entered the voicemail phone number then paused and then entered the password.

Last spring, I purchased a Nokia Lumia 635, and I was trying to set up a similar speed dial number in my contacts. The problem is the lower case “p” represents the pause (approx. 2-3 seconds per “p”). The non-numeric options on the phone are a dash, an underscore, a period, an asterisks and the pound key. Those do not work for creating dialing pauses, but there is a work around.

Since this is a windows phone, you can edit the synced contacts through your Live account’s contact list (ref. https://people.live.com/). Through the Live account you have all the alpha numeric options via your computers keyboard. I simply edited the phone number adding the correct number of “p”s then the contact was updated on my phone (see example below).

Example VM dial-in number: 1-800-345-6789ppp876543#

(Where 1-800-345-6789 is the voicemail dial in number and 876543 is the example password followed by the pound sign.)

The downside of this is if your Live account is hacked, your voicemail password is exposed.

Note, if the contact does not show up or update on your phone then go to your phone’s settings, tap Email+accounts, then tap-and-hold Microsoft account (or Windows Live) and then tap sync.

That’s it.  Just thought I would share my work around.

Good Luck.

Gateway 2000 P4D-66 – Update (Problem Solved)

My computer issue has been solved (see previous blog post)!!! I found a CMOS chip that has an onboard battery. The problem was definitely a dead internal CMOS battery. When I ordered the first replacement chip, it was not clear if the chip had an internal battery. Even after receiving it, based on documentation, it was still not clear if the new chip had a battery. I now know that it did not. In addition, there was not enough information on the original chip to know if it had a battery or not. It did. It was dead, and that was my problem. But it was all unclear at the time. After some contemplation and some searching online, I found a chip that specifically stated it had an onboard battery. I took a guess that maybe the old one did, too.  When the new chip arrived, I installed it and the battery error was gone. Yay!! For reference, below is the old chip’s information and the new chip’s information. Old Clock Chip: Dallas DS12887 Real Time 9414AZ 044328 Korea 230AA (On bottom of the chip) New Clock Chip: Dallas DS12887A Real Time 13256F 390245 Phillippines + Ah, but my troubles were not over.  Even though the battery error was gone, my machine would not boot.  I got two errors: “2F8h IRQ Com Conflict” and “Failure Fixed Disk 0” For several hours, I rummaged through old boxes and piles of floppy disks (remember those?), looking for installation help. I had a lot of custom configuration with this machine to support a larger hard drive, SCSI, and everything else. It seemed to me (via some faint memory) that I had to do something custom with BIOS to get the hard drive to work. It was a long time ago and my brain is getting old. Playing around with BIOS setting, I did solved the IRQ error by disabling the COM B port. I don’t use it, and it seems to me (again via some faint memory) that maybe it was previously disable.  (Oh, the woes of changing your CMOS chip.  Nothing like loosing your BIOS setting, especially on an old machine.) Now to solve the fixed drive problem.  There was a lot of trial and error. Eventually, in the BIOS settings, I found a setting that did the trick. Under the “Advanced” menu by changing the “Large Disk Access Mode:” to [Other] (versus [DOS]), this caused the fixed disk to be recognized. The machine booted up. Yay!!! Because computer also had EZ-BIOS load on it (which I forgot about) to handle the large hard drive, EZ-BIOS took over after the normal BIOS was done, and everything booted up just fine.  The Gateway 2000 P4D-66 came back to life. All is right in the world again, and I have my favorite scanner back.

The Lost Poem

Back in the 1990s, I hurriedly scratched out a whimsical poem. It got a positive review from a lone reader. Shorty after that, the poem went missing. Often I wondered what happened to it. Then several years ago, I found it. Naturally, I stored it in a safe place, and then I could never find it again. Well, last night while looking for my deck of magic cards, I found it! In order to make it easier to find, I told myself if I ever found it again that I would post it online, so here it is. It was not titled at the time, but I call it “The Lost Poem”



“The Lost Poem”

Dark blue mountains, jagged and high
Divide the earth, from the sky
The mountain streams, turn to lakes
The forest cooks, some pine cone cakes
The fairy whispers time in my ear
I ran from the wind, and hid in the clear
I wandered in, and with a thought
And pondered a, Shakespearian plot
Then I dove into, clouds up high
And touched the stars, in a wink of an eye
Stretched a thought, to its elastic limit
Lost some time, and found a minute
Counted stars, with a satellite
Did a dance, on waves of light
Played marbles with, a parasite
Stopped two doves, in a fight
Tickled a gnome, with a horse feather
Listened to, a piece of old leather
Then I stepped, in through time
And found myself, in a rhyme