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Hobby Series - Breadboards Mystery Cache

This cache has been archived.

Hydroid: With the passing of my four legged geocaching buddy, and the ever worsening tick issues, I’ve decided to archive my remaining caches….
Was fun while it lasted.
Time to open up the area for someone else.

More
Hidden : 3/20/2016
Difficulty:
3.5 out of 5
Terrain:
2.5 out of 5

Size: Size:   micro (micro)

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Geocache Description:


The gate at the posted coordinates is a good road-side parking spot and makes a good place to start your trek. The cache is within 1km...

As this cache is located on Nonquon Crown land, and hunting is permitted, it would be advisable to wear bright colours (Blaze Orange, perhaps) during hunting season. Also, you might wish to keep pets on a leash and refrain from suggesting the 'better-half' wear that 'Antler-Hat', just for fun...

This is the fifth part of a seven part series (6 caches plus a FINAL). Each part will build on the preceding part, so while not impossible to do out of sequence if you have the knowledge, it is suggested that you do the caches in order:

1 - GC6DDCH - Resistors
2 - GC6DKK8 - Series & Parallel
3 - GC6DR23 - Ohm's Law
4 - GC6DR2X - Magic Smoke...
5 - GC6DR3G - Breadboards (This listing)
6 - GC6EG5M - PCBs
7 - GC6DDDW - FINAL

Note: Each of parts 1 through 6 contain bonus information that's written on the top of the log. If you plan on doing the FINAL, please record this information as it will be required.


Breadboards:

No, not those kinds of breadboards... In electronics, a breadboard is a device that allows for prototyping electronic circuits without the need for soldering of components:

 






The breadboard, above top, is made up of strips that have spring terminals at each physical hole in the board. These internal terminals are shown external to the board in the bottom image above. The above centre image shows the electrical connections of the holes, or tie points as they're called. The upper horizontal row of holes highlighted in red are all connected together as are the lower horizontal row of red holes, but the two rows are not connected to each other. The same is true with the upper and lower horizontal rows of blue tie points. This is done so that the board can support different voltage levels. For example, if a circuit you were designing for automotive use had micro controllers, then you would be using 12V to interface with the automotive side of the design and 5V for the micro controllers and other components that operate at 5V. Thus, you could connect the 5V supply to the upper red and blue columns of tie points, and 12V to the lower two red and blue columns of tie points.

The upper 63 vertical columns of 5 ties points each, highlighted in yellow, are connected together - in individual sets of 5 as shown. The same is true of the lower 63 vertical columns of 5 tie points each. Two different colours were chosen to indicate that the upper and lower sets of columns are not connected together. The connection stops at the centre horizontal channel. If you look closely, you'll see that the tie points in the central area of the breadboard have letters a-j on the vertical and 1-63 on the horizontal. So the upper left tie point would be designated as "i-1" with the lower right being "a-63". Circuits for beginners often utilize these letters and numbers to indicate where to "plug-in" a particular component while making a circuit. 

Let's look at an example of how to use it, which should make its operation easier to understand. Let's use this schematic:



A term we haven't discussed before are rails. In a schematic, the positive and negative power supply lines are shown as horizontal lines at the top and bottom of the schematic - and are known as the power rails. Upper for positive and bottom for negative. The circuitry is drawn between these two rails. Here we have the rails being supplied by a 9V battery - 9V shown on the left, with the upper rail designated as positive (+ sign in the circle) and the lower rail as negative (- sign in the circle). The circuit consists of a red LED with its 300
Ω dropping resistor R1 on the left hand side of the schematic. On the right hand side are three resistors - one in series with the other two connected in parallel. There's really no point to the circuit consisting of R2, R3 and R4 - other than to generate heat. They are there just to illustrate how to use the breadboard...

This is what the above schematic looks like on the breadboard. For clarity, I've only shown the section of breadboard with the components:



The 9V battery is out of the picture to the left, but its positive red lead and negative black lead can be seen entering the photo from the left. Using tie point designation ID's to help show the connections, the left hand schematic section, showing the LED and its dropping resistor R1, are connected as follows:

Jumper wire : + rail to i-9
R1 : f-9 to e-9
Red LED : d-9 to d-10
Jumper wire : a-10 to - rail.


Similarly, the right hand schematic section, consisting of R2, R3 and R4, are connected as follows:

Jumper wire: + rail to j-12
R2 : h-12 to h-15
R3 : f-15 to e-15
R4 : g-15 to e-17
Jumper wire : a-15 to - rail
Jumper wire : a-17 to - rail


To further illustrate the connections, here's the same breadboard photo with the internal connections highlighted:




The Cache:

To find the cache, you are going to have to determine some information from this breadboarded circuit:



I have only shown the part of the breadboard that is relevant. There is nothing else on the breadboard.

In case the resistor colour bands are not clear enough, and to ensure its clear which tie points components are inserted into, I will give the component information and tie point designation ID's as was done above. I have labeled the resistors in the photo. For the four resistors R1, R3, R4 and R5, the colours listed below represent their order from top to bottom in the photo. For R2, the order represents its colours bands from left to right:

R1 (Yellow, Violet, Red, Gold) : + rail to j-4
R2 (Gold, Red, Red, Red) : i-4 to i-7
Jumper wire : + rail to j-7
R3 (Brown, Black, Red, Gold) : + rail to h-9
R4 (Gold, Brown, Violet, Red) : + rail to e-10
Jumper wire : g-4 to g-9
R5 (Brown, Grey, Black, Gold) : f-4 to b-4
Jumper wire : f-9 to e-9
Jumper wire : d-9 to d-10
Jumper wire : a-4 to - rail

North decimal digits : Calculate the circuits total resistance, RT, round it off to the nearest ohm, then divide that value by 1,000. Replace the posted north decimal digits with that result.

West decimal digits: Calculate PR4, the power being dissipated by R4, round that value to the nearest hundredth of a watt, then divide that value by 10. Replace the posted west decimal digits with that result.

Note: The circuit is being powered by a 5V power supply. Assume each resistor is exactly the value given by its colour bands, regardless of the tolerance indicated.

Hints:
- Don't assume that just because a jumper wire is red, it is always connected to the + rail..
- The jumper colours have no meaning. Usually, red indicates positive and black negative, but they are just pieces of wire - they don't know what colour they are..
- You might want to reverse engineer the breadboard circuit back to a schematic diagram for clarity..
- Remember what Resistors said to do if the first resistor band colour was  Gold or Silver?

In case you want to double check your answer before heading out, click here

Congratulations to MythicLionMan on his fourth FTF of this series
Notes:
- Please bring your own pen / pencil for the log.
- This trail, depending on the season, can be icy, deep in snow, or be quite muddy - use caution.
- There are trails that take you pretty well to GZ - but which trail(s)...?

Additional Hints (Decrypt)

Pnpur: Ynetre guna n svyz pna; Prqne, rlr yriry. Lrnu, gurer ner n ybg bs prqnef...

Decryption Key

A|B|C|D|E|F|G|H|I|J|K|L|M
-------------------------
N|O|P|Q|R|S|T|U|V|W|X|Y|Z

(letter above equals below, and vice versa)