Bert found Bart experimenting with a strange device, which seemed to have strange effects on old Fido, the school mascot dog. Whenever Bart pressed little button on the device, some kind of mysterious transmission that Bert could not identify happened, and the dog came running from wherever it was.

Nothing was heard, nothing was seen coming out of the device, which made Bert even more curious and amazed. He had no doubt: after the third trigger of the device came over and asked:

 

- What the hell is it? An "E-Dog Caller"?

 

Bart laughed, but it didn’t stop him from giving the necessary explanations to his friend:

 

- I'm working with "animal conditioner" circuits and this one is quite interesting, because it works with dogs and all animals that can hear ultrasound.

 

- Ultrasounds! That’s why I didn’t hear anything! - Bert interrupted.

 

- Exactly! The idea is simple: you generate an ultrasonic pattern the dog identifies perfectly, and then you make a conditioning work.

 

- Conditioning? - Bert asked, surprised with the term.

 

Bart wasn’t surprised with his friend’s shocked face, he just continued his explanations, still holding the small "device":

 

- Yes, "conditioned reflex", do you remember what Professor Ventura once explained about Pavlov?

 

Bert now remembered the subject:

 

- Ah! Now I do. That "guy" who conditioned dogs to salivate when they heard a bell and proved that this was a "reflection" which was naturally induced in animals after many experiences!

 

- That's right! This fact is what enables us to train animals, which in fact have little intelligence to "learn" things. We make the animal associate, for example, an order of "sit" with the act we initially forced. After a while, it becomes a "reflection" and when it hears the word "sit" almost unconsciously it repeats the operation!

 

Bert was actually interested on his friend's gadget, and by then he had already understood how it worked:

 

- So you "blew" it a “many times” this thing on Fido’s ears, always giving it a" reward ", and now it is" conditioned ". When it hears the "beep" it runs thinking about the treat!

 

- Exactly! And it was very easy, considering that Fido is crazy about popcorn!

With that said, Bart pressed the small button on the ultrasonic emitter and the dog, who was already a little away from the two of them, ran back.

 

Bart, to lose the conditioning, took some popcorn out of his pocket and gave them to the dog who "thanked" in Canine language: wagging its tail and eating quickly.

 

- We cannot stop giving the treat often as it can lose the "conditioning"! - Bart said, giving some more popcorn to Fido.

 

Bert still looking at the scene was excited, but at the same time embarrassed by the possibility of using it for such a thing:

 

- But what the hell is this for, besides "activating" old Fido?

 

Bart, who had a broader view of things, gave several examples:

 

- We can train animals so that they only respond to the command of a person.

For police dogs it would have great utility. Even in a trained animal show this could be used.

 

- In a circus, for example?

 

Bert had hardly said that, by coincidence, entered the school street what looked like a large caravan: animals, a band (which was not Tubald’s) and a car with a loudspeaker announcing that the "Great Circus Internazionalle d'Italia" was arriving in Lemon city.

 

In fact, large and which remembered something international, there was only the female elephant Carmela, and the director Giuseppe Stromboli, an Italian wearing long boots and a mustache, wielding a whip ...

 

The rest were some jugglers, clowns and some "national" trained animals such as a "mathematical" donkey, a group of leaping dogs, an old lion without teeth and monkey with a sad face.

 

The circus parked exactly in the large empty lot in front of the school, and it would work there for a "season" of one or two weeks.

 

Bart looked at his friend when the "caravan" parked and commented:

- Speaking of the devil! Maybe someone even gives us the opportunity to make some "tests" with the animals!

 

Bert agreed with his friend:

 

- Not a bad idea! Since we don’t choose the lion!

 

The subject was forgotten for some time, and meanwhile Bart continued to "have fun" with his "canine conditioner," as he started calling the "ultrasonic oscillator".

 

Demonstrating to Professor Crick, the school principal, and other non-electronic area teachers plus some staff he had impressed them with the ability to "control an animal at a distance" by means of an electronic device!

 

Only Professor Ventura laughed at the project, knowing that in reality it contained no "miracle" setting.

 

But what Bart did not know was that there was someone else very impressed with the "gadget".

 

In one of the demonstrations, at the school yard, they did not realize that there was someone who watched, far away and wide-eyed, stunned and very interested at the strange device!

 

It was Giuseppe Stromboli, the Italian circus director, who did not believe on his eyes:

 

- "Madonna Mia Uno Controllo Remoti per cane"! (Oh My God! A remote control for dogs!)

 

He did not hold back, and when Bart and Bert were alone in the courtyard, still playing with Fido, he approached.

 

"- Buona Sera!"

 

- Good afternoon! - The boys answered, even without understanding Italian, realized that the mustachioed circus director with a hat, boots and carrying a huge whip, greeted them. And in an English mixed with Italian, he went straight to the point:

 

- I could not help but notice the wonderful device that you used to call "vostro cane!" It would please me very much to know how I can get "uno"! In fact, I want to buy it! I wonder how successful it would be in "mio" circus if I could control the animals like you’re doing!

 

Of course, the director of the circus that had observed the demonstration from a distance, did not know that it was a "conditioner".

 

With brief explanations Bart tried to show the Italian that the device simply emit ultrasounds and that the "work" with Fido was just training!

 

But, unlike what Bart expected Giuseppe was not disappointed:

 

- "Magniffico"!

 

And, placing his hand on his long beard as someone who has a great idea he whispered to Bart and Bert what he wanted:

 

- "Vero"? If it's "solo" it then I have "una buona" idea! Why don’t you build me "uno" of these "conditioners" so that I can use to call the female elephant Carmela! It would make a huge success and it would be easy to train! I pay you very well if you help me!

 

Bart did not get excited about ??receiving some money but it was another story about "testing" his device on a different animal.

 

- An elephant! Gee, it would be interesting to test this control on an elephant!

 

Bart, even before Bert could try giving an answer, agreed with the circus director.

 

- We will help you! We can put together a "remote control for elephants!"

Giuseppe interrupted:

 

- For a female Elephant! It's her! Carmela is "una dama"!

 

At this point Bart imposed his conditions:

 

- But to know what kind of signal we have to use, we must first run some tests! We do not know if elephants can hear ultrasounds!

 

The Italian did not put obstacles to the boys:

 

- You can come and go any time you want!

 

Thus, an interesting idea of assembly started to configure for Bart and Bert, so as soon as they could they quickly went looking for Professor Ventura’s help.

 

- Try to check what kind of sound is easily perceived by the animal! - It was the first suggestion the professor gave.

 

- Not this one! Make the "response curve of an elephant!" Now there's a job that I have never seen in any book of electronics! - Bert commented ironically.

 

- Neither on the information series "Circuit Bench”, Newton C. Braga predicted this - added Professor Ventura while laughing. You, reader, may find something on www.newtoncbraga.com website.

 

Next morning Bart and Bert went to the circus taking the ultrasonic oscillator, but with a slight modification: they put a frequency control allowing the signals to vary from 18,000 to 40,000 Hz.

 

They would try all frequencies until they got the one that would sensitize more the animal, because they couldn’t find information in books about the "audible range" of elephants!

 

In front of of the friendly animal, which soon Bart and Bert conquered its trust with the help of some peanuts and so they started doing the tests.

 

They gave peanuts to the animal and at the same time "they triggered" the device, repeating twice or three times the operation in the same frequency, and then moved away.

 

Then they used the device without the peanuts, and checked the animal's reaction.

 

- If it hears the ultrasound it will have a reaction and should come looking for the peanuts! - Bert commented.

 

Nothing!

 

They did this in all the frequency range scanned by the device and nothing! No reaction from the animal.

 

- Maybe that's deaf! - Bert commented discouraged.

 

- It cannot be! Because it answers to our calls. Maybe it cannot hear ultrasounds, but if we use audible sounds, there is no fun!

 

The two were quiet for a few moments until Bert had an idea:

 

- What if we modulate the ultrasound on a low frequency?

 

- It's not a bad idea! Let's see what Professor Ventura thinks.

 

Both of them told what they wanted to the Professor who then suggested a circuit that generates an ultrasound modulated at a frequency around 60 Hz, which would be more agreeable to the acoustic characteristics of the huge animal's ears!

 

- I think in a low frequency, something that sounds like the sound of another elephant, modulating the main signal, can cause some "deeper effects." It should be a sound that has a more complex pattern than a simple frequency! I have no idea ??what it could be, but we can try! ...

 

And they tried!

 

The circuit developed was very interesting: Bart took a digital recorder and connected it to a 555 generating ultrasound around 30 kHz.

 

The 555 was connected to a power amplifier stage with a power MOSFET having as a load a piezoelectric tweeter and a mini woofer, like the ones used in home theater.

 

Powered with 4 rechargeable batteries it gave a good audio power.

 

But what to put on the digital recorder as modulation?

 

Bart and Professor Ventura were thinking about it when Bert jumped from his chair, looked at his watch and said:

 

- There's still time!

 

He took his small tape recorder and ran, taking time only to say a word:

 

- Wait!

 

Bert returned after an hour and immediately engaged the output of his tape recorder to the digital recorder to where he downloaded the strange contents of the tape. Bart and Professor Ventura could not hear anything because the transfer was direct.

 

Very curious, they still tried to get some information from Bert which simply replied:

 

- Keep calm! I got a good standard of low frequency for our tests. If it works, then I tell you what it is!

 

He took the tape from the recorder and put it on his pocket it with some affection.

 

Immediately they went to Carmela who received them happily expecting a lot of peanuts.

 

This time it did not take many tests.

 

On the first touch when Bert offered peanuts to the elephant, the reaction was strong, and quite unexpected, too: the heavy animal despised the peanut,and came forward making a strong roar, but in a "loving" way!

 

It seemed to want to hug them with its trunk!

 

- It's working! - Bart exclaimed excited.

 

For the boy’s surprise, on the second ring, even without offering peanuts, the elephant ran to where the machine was trying to catch the small device with its trunk!

 

- It likes the device! - Bert commented.

 

- It must be the sound pattern! But what devil’s modulation did you use?

Bert did not answer, making some "mystery." He would tell afterwards...

 

The owner of the circus, after attending the demonstration, was thrilled!

- "Grazie!" Fabulous! Fantastic! Stupendous! It works!

 

He wanted to take the "conditioner" right away, but Bart and Bert, prevented by asked for more time:

 

- We need to adjust the device and make the "conditioning" of the animal. Two or three more days will be enough!

 

- "Vero?" Being ready for "sabato" when we will debut, it’s good! - Giuseppe agreed.

 

Bart and Bert left, not realizing that the female elephant stared at them in a weird way! Its behavior had changed entirely, but this would only be discovered later.

 

Given the positive results Bart even forgot to ask his friend about the "devil’s" modulation he had recorded on tape and transferred to the device.

 

Except for new circus, which would open for the first time on the weekend, life in Lemon city suffered no changes, at least for now.

 

At dusk, the band would play again at the bandstand and Tubald Weathercock, with his powerful tuba, would give a further demonstration of his lung strength and talent.

 

This time he would play more willingly, to show that his band was much better than the circus’, which actually he had no pretension to compete.

 

- There is tuba! Imagine a band without a tuba! -Tubald commented incredulously with his fellows from the Musical Corporation.

 

One after another, the marches from the Lemon city Glorious Musical Corporation filled the night air, cheering people, but also having a very strange effect on a certain being that had come to the city in the past few days: the female elephant Carmela!

 

The strange modulations Bert had recorded and placed in the "conditioner", eventually sensitize the animal in an interesting and totally unexpected way!

 

Much more than that, it moved “her”, messing with her feelings!

 

Hearing the sound of the band, the female elephant was troubled and after forcing the chain that held its leg to a stake, ended up breaking it and escaping!

 

No one noticed it, and it went freely through Lemon city’s streets.

Its destination: the square where the band played, but it did not advance directly against the source of its disturbance.

 

Carmela hid behind a bush and simply watched!

 

It admired, quiet and absorbed, away, with a passionate look at the source of such "wonderful tones" that had shaken “her” heart!

 

Where did these such sweet tones come from for the huge animal?

 

Tubald’s Tuba, of course!

 

When the band finished the presentation, and the people went away, leaving the empty square, only Carmela remained impassive in hiding and watching carefully, it saw when Tubald wielded the tuba to walk his way home.

 

Carmela followed him, keeping a distance, but couldn’t not hold back: it started gradually approaching...

 

Whistling a Sousa´s march, Tubald was already on the top of the hill, toward Newville where he lived, when he noticed a strange 'breath' on his back.

 

He shrugged shivering and slowly turned around until he faced the huge female elephant! He had no reaction:

 

- Wow!

 

Panicked, his first reaction was to try to run, but the female elephant held the tuba!

 

He had no doubt: he made a huge effort to save it.

 

After all, he thought, "- no animal, no matter how big, will try to snatch my beloved tuba! I’d die trying!" - Until he got it!

 

He ran away downhill, with the tuba under his arm and the clumsy female elephant chasing him!

 

Tubald found the front door of his house opened, and going in like a rocket he went straight to the room where he dove, with tuba and everything under the bed, but not before shouting:

 

- Ginevra! Help!

 

Mrs Weathercock, who had seen this scene many times because whenever he was "in danger" he did it, got a broom and went to help her husband!

 

Of course the reader does not expect the elephant to also be stuffed under the bed, along with Tubald and his tuba, for the heavy animal couldn’t go through the door.

 

Ginevra entered the room “armed” with a broom, just in time to see the female elephant outside, with its trunk through the window, pulling the tube from Tubald who, under the bed, screamed trying to prevent with all his strength it to be swept away.

 

- Let it go! Crazy beast! …

 

Some broom hits from Mrs. Wheathercock made Carmela drop the tuba and back off a bit.

 

It was then that some men from the circus, which alerted by neighbors came looking for the female elephant.

 

They found Carmela staring sadly looking at the Weathercock’s house window.

 

- This weird animal got crazy over my tuba! - Tubald said, cleaning his clothes after crawling from out under the bed, still protecting his beloved instrument!

 

- I wonder what got into it. It’s never done it before! - Said the trainer who came after “her”.

 

Bart and Bert heard about it the next day.

 

Bert seemed more worried than Bart, but did not say why.

 

They continued to experiment with the "conditioner", but carefully, as the owner of the circus and the trainer had commented that the animal's behavior was "strange." But for Bart and Bert Carmela continued to be friendly: it seemed to like the signals from the "conditioner".

 

However, what no one could foresee is that that night, new problems would occur involving Carmela.

 

As soon as the band started playing in the square the female elephant got impatient.

 

After all, it could hear the tuba "wonderful tones" coming from where Tubald was, and God knows why it was messing with the animal’s feelings.

There was no way to contain Carmela: it got so impatient that even next to the trainer, trying to calm it, the female elephant escaped and, after a strong roar, went straight towards the square.

 

- Hold the "beast"! - It was the only thing one could hear clearly, right before the mess that followed when it left in a hurry to the main street!

 

The people in the square, noticing the “runaway”, had no doubt: they scattered!

 

And the band when realized it was heading straight to the bandstand also scattered!

 

- Save yourself if you can! - Maestro Ronald screamed throwing the baton and jumping out of the bandstand.

 

But the most frightened was Tubald who realized it was him that the female elephant was looking for!

 

The huge animal was staring at him and started running towards his direction!

Again, he shivered all over and put the tuba under his arms, running, leaving only time to scream:

 

- Wowwww!

 

And again the scene repeated itself: Tubald with the tuba under his arm running one mile and a half to his home with the runaway female elephant pursuing him!

 

Right behind, running as fast as they could, came the trainer, some employees and the director of the circus!

 

Tubald ran into his house, and again crossing his living room like a rocket, went to his bedroom where he dove under the bed.

 

- Ginevra! Help!

 

The men from the circus, who had reached the female elephant, were able to control it and carried it back.

 

- It's not possible! It’s never done it before! - Commented the trainer.

 

- It's the tuba musician! It goes after the tuba! - Said another employee who realized the intentions of the female elephant.

 

- It likes the tuba! Amazing! - Said someone in the small crowd that had formed around Tubald’s house.

 

Tubald, terrified, did not dare to leave the house, while the animal was not far away.

 

Wielding a broom "to defend to death his beloved tuba" he kept "guarding" spying through the window. The only comment that could be heard was the following:

 

- Again! It's not possible! This animal is crazy about my tuba!

 

Giuseppe Stromboli, just watched the strange scene, while tampering with his long beard.

 

Until, at some point, it finally “snapped" and he realized what was happening:

 

- "Oh boy!" Carmela is "in love" with the tuba "Signore" Tubald!

 

The group of people who had gathered at the site started laughing! And the news spread!

 

- In love! With Tubald’s tuba! - Bart and Bert did not believe what they heard when the director explained what had happened.

 

Even the local newspaper had already taken advantage of this fact and in its edition that day announced with fanfare:

 

"Love Triangle Nearly Ends in Fight - Tubald tries to attack the female elephant Carmela, lover of his tuba!"

 

It was weird to analyze how that was possible, how determine the "gender" of the tuba? The name sounds feminine, but the tone is serious! ...

 

The city was having fun with it, with the jokes multiplying, but for those involved in the issue the "thing" was serious.

 

In the circus, the boys and Professor Ventura with Stromboli Giuseppe and Carmela’s trainer analyzed the case:

 

- But why? Did our conditioner "messed up" the elephant’s the feelings? I do not believe! It has nothing connected to this case! - Said Bart.

 

Bert, who was near, with a concerned face, pulled his friend aside by the arm and finally confessed:

 

- Friend I think the conditioner has a lot to do with this case!

 

-What?

 

Faced with Bart and Giuseppe’s blank expression he explained:

 

- It is my fault! Do you remember that Professor Ventura suggested we used a low frequency modulation for the ultrasound emitted by the conditioner?

 

- Yes, and you came up with the recorder! Wait! What the hell of low-frequency tone did you record? Do not tell me ... - Bart was beginning to realize things, but never finished:

 

- That's right: Tubald’s tuba! I knew he was rehearsing after lunch, at least half an hour in the barbershop. I went there with the recorder, and without him noticing, I recorded part of it!

 

- Damn it! I’m beginning to get it. The modulation of the tube tone messed with the female elephant’s feelings and, acting on its "subconscious", made it fall in love with the sound of the instrument! When Tubald played in the band it recognized the sound immediately, and didn’t hold back anymore! - Bart reached the root of the problem.

 

- I'd like Freud to be here! - Commented Professor Ventura who was quiet until then.

 

- I do not know if I could make the "patient" lie on the couch! - Bart concluded with good humor. But the thing was serious and Bert, feeling guilty, did not laugh.

 

To Giuseppe Stromboli the problem needed a quick solution:

 

- And now! "Ma che disastro"! Do we have to hold Carmela every time "Signore" Tubald plays?

 

It really would be a problem, and it was!

 

That night again it took a lot of effort to hold the female elephant when the band played at the bandstand.

 

Tubald was very worried!

 

In fact he sweated constantly looking at all sides, especially at the street where the circus was, while playing.

 

He was alert to see if "the bloody beast did not appear again after his tuba!"

The next day Bart and Bert met the director of the circus who was still very worried.

 

In fact, the female elephant was depressed, agitated and seemed to not want to obey the trainer.

 

The small device "conditioner" was the only thing that produced some effect on the animal now!

 

- We cannot depend only on the conditioner! I’m glad you came! I need you to help me "cure" Carmela! - The director of the circus was agitated.

 

Bart and Bert felt responsible for the problem and agreed to help, but how?

 

They could not prevent Tubald to play in the band, and moreover, the circus would be in town for at least two weeks!

 

Bart thought about a solution to the serious emotional problem of the female elephant for a long time, until he had a great idea:

 

- I got it!

 

Bert, who was next door, could not wait for the solution.

Bart started explaining, thoroughly, what he intended to do, and the idea was very interesting!

 

- Damn it! An MP3 for an elephant!

 

- No! A "MP3phant"!

 

The idea was simple:

 

Carmela was "in love" with Tubald’s tuba music and could not live without it.

Why not "adapt" a common MP3 to an "oversized" phone and put it in the elephant with the songs that has tuba?

 

They consulted Professor Ventura, who also found the idea interesting:

 

- Let’s try it!

 

Then they took a common MP3 and prepared an amplifier powered by larger batteries, driving two 8-inch speakers (20 cm).

 

They padded the two speakers and prepared a clip with the head size the elephant. It looked like a huge headset that was perfectly suited for the animal!

 

The recording: a track of "The Lemon city Glorious Musical Cooperation" with the special participation of Tubald Weathercock and his "powerful tuba."

 

A special reinforcement in the low sound, obtained from an equalizer circuit, made sure the sound of the tuba was clearer, and it worked!

 

- Wonderful! Fantastic! It is better that the remote control! - Giuseppe exclaimed glad to see the machine in operation in the circus parade announcing the inaugural show.

 

Carrying the MP3 and the amplifier, the female elephant marched happily, following the rhythm of the music.

 

It seemed to dance!

 

In fact, it danced! Affected by the sound of Tubald’s tuba on tape, with complicated steps that provoked applause and laughter of the people who stopped to see it through, the elephant looked very cheerful and happy!

 

- I never thought Epaminondas could have such a big fan! - Bart commented laughing.

 

- Big in every way! I just hope it doesn’t decide to ask for Tubald’s autograph! - Bert completed.

 

- Let’s make sure it doesn’t happen! Just thinking about looking at Carmela, Tubald "shudders!" - Professor Ventura was right about the musician’s fear.

 

- It is true! Poor Tubald! He’s been a little scared with the presence of the female elephant in the city!

 

It was then that the old master had the idea of playing a trick on the musician.

 

Bart and Bert realized the diabolical expression of the teacher, he was up to something!

 

Bart poked Bert who soon noticed what was going on.

 

They did not interrupt the professor, for they knew that he would tell them what he was about to do. In fact, they were not only told afterwards about the game as they were "invited" to participate.

 

- It's not quite a joke, but a "scientific experiment"! - Justified the professor after explaining the "electronic devilry" he intended to carry on.

 

Going to the circus, on the pretext of seeing Carmela, Bart could induce the animal to give a "beautiful" roar that was recorded on a pen drive.

 

Professor Ventura then connected the pen drive to a portable amplifier, but very powerful, he put it on the bandstand, behind the Tubald’s place, just before the band performed.

 

The devices were activated by a remote control.

 

Nobody from the band was bothered by the presence of that box, because it was common stereo systems to stay in place for playing music when the band did not appear, or when musical groups of young people made their shows.

 

- It will be interesting to see Tubald’s reaction! - Commented Professor Ventura with a remote control in hand.

 

The presentation of the band began normally, with Tubald playing careful and looking a little scared, because after all, "she" was still in the city and if “she” escape! ... Brrr!

 

"-While this animal is in town, I can’t get calm!" - Thought the musician with an "eye on the score and another on the circus street," while playing!

 

In the midst of a march, Professor Ventura pressed the remote button and immediately a strong elephant roar was played just behind Tubald!

 

The shock was so great that he shivered again blowing on the tuba all the air he had in his lungs!

 

The result was a second "roar" that, according to witnesses, seemed as from a larger elephant than the first!

 

- They would make an interesting couple! The tuba and the female elephant! At least in terms of sound, they combine! - Said a "joker" after the confusion.

 

The band stopped frightened, and everyone stood looking for the "elephant":

 

- Where is the elephant?

 

- Where's the "beast"?

 

But there was nothing! And there was no time to say that to the tuba player!

Tubald, out of breath, immediately after the "roaring" note, got up and ran, but not before giving his traditional cry of terror:

 

- Wow!

 

And again, without looking back, Tubald beat the record and a mile and a half that separated him from home!

 

Professor Ventura, half scared, hid the remote, sorry about the game that had given much stronger results than expected.

 

Embarrassed trying to "sneak" out, recalling Pavlov, he made only a short comment to Bart and Bert, who were by his side:

 

- Conditioned reflex!

 

 

 

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