Memo: One-shot timer and op-amp filters

Integrators and Differentiators are basic building blocks of analog computers. They enable summation and subtraction operations (hence, the core component of them is called “operational” amplifier). For multiplication, multiple integrators are used in parallel, along with exponential and logarithmic elements (non-linear op-amp circuits), to achieve the effect via the following transformation:

ln(ab) = ln(a) + ln(b) = c

e^(c) = ab 

This is why analog multiplicators are expensive, costing up to $20 a pop.

All the circuits below require very specific values for their components. Changing the value of the components will do more than changing the properties of the output, it can cause instability and disrupt the circuit’s operation. As an oscilloscope is required to diagnose these circuits, some preset values that have been tested in the lab are also included in this memo for DIY projects at home.

Monostable multivibrator (one-shot timer)

Monostable multivibrator has one stable state and it will change to the unstable state for a period of time when a trigger pulse (negative edge) is introduced as input.

The circuit can be derived from astable multivibrator circuit; the only new addition is the grounded diode in parallel to the output capacitor. If all values are appropriate, connecting the diode will dampen all output and (negative) feedback generated by the powered astable multivibrator without any input. After this dampening characteristic has been achieved, negative edge trigger input can be introduced to complete the circuit.

The basic circuit is as seen below:

basic op amp monostable
Basic monostable multivibrator: R1 = 10K, R2 = 2.2K, R = 1K, C = 1uF
op amp monostable waveforms
Measuring the voltage behavior across the capacitor C yields a shark-fin waveform

The timing period T is the amount of time it takes for the circuit to return switch from unstable back to stable state. The timing period is given by

T = RC ln[1 / (1-B)]

where B is the regenerative feedback as described in Memo: Schmitt trigger. The units of the remaining variables are as follow:

T: seconds (s)

R: ohms (Ω)

C: farad (F).

Cheat sheet: when R1 = R2, the timing period T = 0.693 RC

Similarly, the charging period is the amount of time the circuit must wait before it can be triggered again. This is given by

T(charging) = RC ln[(1+B) / B]

In some circuits, an additional RC differentiator circuit can be connected to the input (sometimes, only a single 0.01uF capacitator is sufficient). The purpose of this extra circuit is to transform rectangular signal into trigger pulse signal as seen below

rc differentiator circuit
RC differentiator

The complete monostable circuit is as follow:

op amp monostable circuit
Final monostable multivibrator with RC differentiator
Integrator

Integrator functions like an average filter, it’s often used as a low-pass filter.

Inverting integrator: C = 0.01uF, R = 1K

The output of the integrator is given by

V_{{{\text{out}}}}(t_{1})=V_{{{\text{out}}}}(t_{0})-{\frac  {1}{RC}}\int _{{t_{0}}}^{{t_{1}}}V_{{{\text{in}}}}(t)\,\operatorname {d}t

or in Laplace domain, it is

Vout = -Vin/(sRC)

If the integrator starts from zero (no charge in the capacitor), the output is simply given by

-{\frac  {1}{RC}}\int _{{t_{0}}}^{{t_{1}}}V_{{{\text{in}}}}(t)\,\operatorname {d}t

where Vout(t0) represents the output voltage of the circuit at time t = t0.

Op-amp integrator suffers from the same frequency response limitation as other closed-loop op-amp circuits. It has a cut-off frequency at -3 dB and a decreased output at high frequencies. In addition to this, the integrator also has run-away output issue where it can drift to either power rail due to constant noises and it must be reset periodically to prevent this problem.

The drift is caused by any of the three conditions:

The input Vin has a non-zero DC component,

Input bias current is non-zero,

Input offset voltage is non-zero.

A more complex, grounded integrator circuit prevents this drift

100pxl
Grounded integrator circuit

A simple switch in parallel to the negative feedback capacitor allows resetting the integrator to zero.

For the grounded integrator circuit, the output is given by

V_{{{\text{out}}}}(t_{1})=V_{{{\text{out}}}}(t_{0})-{\frac  {1}{R_{{i}}C_{{f}}}}\int _{{t_{0}}}^{{t_{1}}}V_{{{\text{in}}}}(t)\,\operatorname {d}t

Differentiator

Differentiator, in contrast, is a high-pass filter. It has poor high frequency response and any sudden disturbance at the input will cause it to ring at natural frequency

Op-Amp Differentiating Amplifier.svg
Inverting differentiator: C = 1F, R = 1K

The transfer function of the above circuit is as follow:

V_{{{\text{out}}}}=-RC\,{\frac  {\operatorname {d}V_{{{\text{in}}}}}{\operatorname {d}t}}\,\qquad {\text{where }}V_{{{\text{in}}}}{\text{ and }}V_{{{\text{out}}}}{\text{ are functions of time.}}

or in Laplace domain:

Vout = -sVinRC

Read more

https://en.wikipedia.org/wiki/Analog_computer

https://en.wikipedia.org/wiki/Monostable

http://www.electronics-tutorials.ws/opamp/op-amp-monostable.html

https://en.wikipedia.org/wiki/Integrator

https://en.wikipedia.org/wiki/Op_amp_integrator

https://en.wikipedia.org/wiki/Differentiator

https://en.wikipedia.org/wiki/Operational_amplifier_applications

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Memo: Schmitt trigger

Hysteresis definition is as follow:

the phenomenon in which the value of a physical property lags behind changes in the effect causing it, as for instance when magnetic induction lags behind the magnetizing force.

The horizontal and vertical axes are input voltage and output voltage, respectively. T and −T are the switching thresholds, and and −M are the output voltage levels.

In asymmetric bipolar power supply (such as those created by elevating a virtual ground from unipolar power source), the hysteresis can be skewed along the horizontal axis of the above transfer function.

Schmitt triggers vs. Closed-loop amplifiers

It is easy to convert a closed-loop amplifier into Schmitt trigger by swapping the input terminals. Standard closed-loop amplifiers have negative feedbacks while Schmitt triggers have positive feedbacks as defined by Wikipedia:

In electronics, a Schmitt trigger is a comparator circuit with hysteresis implemented by applying positive feedback to the noninverting input of a comparator or differential amplifier.

One important note when converting negative feedback comparators into Schmitt triggers is the direction of the output. As seen below, non-inverting amplifiers will yield inverting Schmitt triggers when the input terminals are swapped, and vice versa.

Non-inverting amplifier (negative feedback)
Inverting Schmitt trigger (positive feedback)

Fortunately, changing the output direction of a comparator circuit (any feedback) is quite simple. Swapping Vin and GND terminals inverses the output direction of the circuit.

Non-inverting Schmitt trigger, practically identical layout with the inverting counterpart except Vin and GND positions
Schmitt trigger’s characteristics

Schmitt triggers are commonly used for switch debouncing and noise filtering for digital signals. In digital circuits, noisy signals are often fed to a low-pass filter to create a smoother signal before passing through a Schmitt trigger to recreate the sharp digital signal. Despite its importance in digital circuitry, the trigger itself is an analog component and is sometimes omitted in digital circuit simulation libraries.

Due to open-loop nature of the circuit, the gain of Schmitt trigger is infinity. Impedance values follow normal op-amp characteristics.

The regenerative feedback refers to the portion coming out of the voltage divider and into the non-inverting input. It’s denoted with beta symbol and defined as follow:

B = R1 / (R1 + R2)

The switching thresholds are calculated as the regenerative feedback times the positive or negative supply rail voltage Vs as seen below

V_\mathrm{+} = \frac{R_1}{R_1+R_2} \cdot V_\mathrm{s}

Please note that despite the formula, in reality, the Vs value in this calculation experiences some voltage drops (around 15%) due to internal impedance; hence the switching thresholds might be lower than calculated.

Astable multivibrator (Relaxation oscillator)

With a few extra components (a capacitor and a resistor), a Schmitt trigger can be adapted into an astable multivibrator. From inverting Schmitt trigger, add an additional negative feedback using a resistor, a capacitor and ground to create the astable multivibrator.

Astable multivibrator adapted from inverting Schmitt trigger circuit

The multivibrator does not take in any input signal. When powered up, it creates a full-range square waveform across the op-amp’s output and a half-range waveform across the non-inverting input (some documents denote this waveform as reference voltage). At the same time, it creates a half-range ramp waveform across the capacitor.

Transient analysis of a comparator-based relaxation oscillator.

The time period of the multivibrator is given by

T = 2 RC ln[(1+B)/(1-B)]

with B is the regenerative feedback, R and C are the value of the resistor and the value of the capacitor across the negative feedback respectively.

The amplitudes of half-range voltages are calculated using the same formula as the switching thresholds of normal Schmitt triggers.

When using an asymmetric bipolar supply, the switching thresholds of the multivibrator will be skewed and it will produce waveform of adjustable duty cycles. The duty cycle is dependent on the offset; left offset produces shorter duty cycle and right offset produces longer duty cycle. However, the device can only accept so much power supply offsetting before it cannot operate (under load) or overloaded.

Read more

https://en.wikipedia.org/wiki/Schmitt_trigger

https://en.wikipedia.org/wiki/Switch#Contact_bounce

https://en.wikipedia.org/wiki/Relaxation_oscillator

https://en.wikipedia.org/wiki/Multivibrator

https://www.allaboutcircuits.com/textbook/semiconductors/chpt-8/positive-feedback/

 

Memo: Op-amp’s gain factor and noise problems

First, here’s a quick cheatsheet on closed-loop gain factor for inverting and non-inverting amplifiers. The gain of inverting amplifier is given by the resistance R2 across the feedback loop divided by the resistance R1 across the forward input.

A = R2/R1

Meanwhile, the gain of non-inverting amplifier is given by

A = 1 + R2/R1

as calculated in the previous note. Kirchhoff’s current law is applied.

Gain factor and cut-off frequency relationship

Cut-off frequency is not only affected by the properties of a given component but it is also dependent on the gain factor of the amplifier circuit. Higher gain amplifiers have lower cut-off frequencies and this can be charted as an exponential decay function.

To easier express this function in linear terms, the relationship is converted to logarithmic terms:

20 log(0.5) = -6.02 [dB]

with 0.5 is the approximated V/Vref value from experimentation.

On a side note, below are two commonly seen decibel functions in electronics for power and voltage respectively.

{\displaystyle G_{\mathrm {dB} }=10\log _{10}\left({\frac {1000~\mathrm {W} }{1~\mathrm {W} }}\right)=30.}

{\displaystyle G_{\mathrm {dB} }=20\log _{10}\left({\frac {31.62~\mathrm {V} }{1~\mathrm {V} }}\right)=30.}

Naturally, the gain factor for op-amps is expressed in terms of voltages (the second formula).

Differential amplifier

A useful circuit using op-amps to amplify and de-noise a weak signal is differential amplifier. The basic circuit uses one op-amp in the arrangement below:

V1 and V2 inputs are the same signal, one of which is inverted. This can be done using an inverting amplifier with gain factor of 1 (inverting unity gain amplifier) but this arrangement is subjected to high-frequency quirks as stated in the previous memo, especially phase shifting property.

If the inputs are identical and not phase-inverted, the output will be zero.

The output of this particular circuit is an amplified signal with transmission line noise suppressed. Note that the transmission line noise being suppressed is the one common on both inputs after the inversion. Noises occurred before inversion cannot be suppressed this way.

Instrumental amplifier (three op-amps)

Normally, to ensure proper signal flow, the inputs are tunneled through two additional voltage followers (two more op-amps) in order to reduce the impedance. The full circuit (called “instrumentation amplifier) would then look like the following:

with all R values are the same except for Rgain.

Rgain can be of any value. It serves as a “common ground” connector and it also tweaks the voltage gain of the full circuit. Increasing the value of Rgain decreases the gain of the differential amplifier.

In reality, the gain of the above circuit can be tweaked further, following this function

{\frac {V_{\mathrm {out} }}{V_{2}-V_{1}}}=\left(1+{2R_{1} \over R_{\mathrm {gain} }}\right){R_{3} \over R_{2}}

Instrumental amplifier (two op-amps)

An alternative instrumental amplifier design using two op-amps can be seen below:

Though this setup saves on component costs, it does have a few disadvantages, notably, the lack of support for unity gain (not a problem for most scenarios but can be if the instrumental amplifier is used solely for noise canceling).

Furthermore, the circuit is unbalanced. The leftmost amplifier increases the input slightly and introduces some signal delay. This unbalance leads to reduced noise canceling capability. The output can saturate if the common-mode noise of the input signal here is too high and race condition can lead to a much lower cut-off frequency (compared to three op-amps version).

The gain factor here is controlled by RG in the same manner as Rgain in the other circuit.

G = 1 + R2/R1 + (2*R2)/RG

Bonus: Choosing the base resistance

When calculating the resistance of an analog system, the first resistor (base resistor) is chosen as a compromise between power consumption and noise tolerance. Low resistance (or impedance for AC systems) allows more current draw. This is welcome when loads are concerned but it is a waste of energy when sensors are concerned. The higher the base resistance, the lower the power consumption will be.

On the other hand, high resistance circuits are more susceptible to noise. The relationship between resistance and noise is given by Johnson-Nyquist noise voltage function

{\overline {v_{n}^{2}}}=4k_{\text{B}}TR

where kB is Boltzmann constant 1.38 x 10^-23 [J/K], T is the absolute temperature in Kelvin [K], and R is the system’s resistance. In other words, a small increase in resistance increases in Johnson noise voltage by the power of two.

TL;DR:

Increase R, increase noise, decrease current consumption

Decrease R, decrease noise, increase current consumption

Choose the right compromise for the application.

Bonus: Using op-amp with a unipolar power source

Unipolar or single-rail power sources that only have GND and VCC terminals need to offset the ground terminal to create a -VCC source. This offset can be done using a voltage divider circuit in conjunction with a voltage follower. Be mindful that the with only half of the voltage range, the op-amp might experience unexpected floating values.

The voltage follower (or unity gain amplifier) must be connected in series to the middle point of the voltage divider in order to create a new, offset virtual ground. This eliminates the added impedance from the voltage divider, ensuring sufficient current draw power devices using the virtual ground.

For example, such a system of voltage divider and voltage follower can be employed to create +2.5V and -2.5V bi-polar supply from Arduino’s 5V and 0V unipolar supply. In this case, the op-amp will produce 5V (relative to the Arduino’s true ground) as HIGH signal and 0V as LOW signal. Inversely, it will see 0V from the Arduino as -2.5V (relative to the virtual ground) and 5V as +2.5V.

The previous section on choosing base resistance also applies here, and even more so with the halved voltage range doubling susceptibility to signal distortion.

Read more

https://en.wikipedia.org/wiki/Exponential_decay

https://en.wikipedia.org/wiki/Decibel#Examples

http://www.electronics-tutorials.ws/opamp/opamp_5.html

https://en.wikipedia.org/wiki/Instrumentation_amplifier

http://www.electronicdesign.com/power/what-s-difference-between-operational-amplifiers-and-instrumentation-amplifiers

https://en.wikipedia.org/wiki/Johnson%E2%80%93Nyquist_noise

http://www.talkingelectronics.com/projects/OP-AMP/OP-AMP-1.html

Memo: Op-amp’s analog characteristics

Operational amplifier (op-amp) possesses an open-loop gain factor A0 and a close-circuit gain factor A.

The negative terminal of the op-amp is called “inverting” terminal and the positive terminal is called “non-inverting”. In addition to two input terminals, there are two power terminal V+vcc and V-vcc.

The output Vout is calculated as

Vout = A * (V+in – V-in).

Ideal op-amp has the following characteristics:

Input impedance rin approaches infinity.

Meanwhile, output rout impedance approaches zero.

Unity gain amplifier

These characteristics see applications in voltage follower (also known as unity gain amplifier), which produces an output voltage equal to input voltage but with much lower impedance. Low impedance circuits allows more current draw than high impedance ones.

Voltage follower setup: a simple negative feedback loop without any resistance

This unity gain is possible because the gain factor used here is open loop

Vout / Vin = A/ (1+A0)

as Aapproaches infinity

Vout / Vin = 1

Gain of closed-loop amplifiers

In other cases, the gain is determined by the values of the voltage divider overlaying the feedback loop. For example

A non-inverting amplifier: negative feedback with voltage divider setup

In this case, the gain is determined using Kirchhoff’s law. Since Kirchhoff’s current law states that the same current must leave a node as enter it, and since the impedance into the (−) pin is near infinity, we can assume practically all of the same current i flows through Rf, creating an output voltage

{\displaystyle V_{\text{out}}=V_{\text{in}}+i\times R_{f}=V_{\text{in}}+\left({\frac {V_{\text{in}}}{R_{g}}}\times R_{f}\right)=V_{\text{in}}+{\frac {V_{\text{in}}\times R_{f}}{R_{g}}}=V_{\text{in}}\left(1+{\frac {R_{f}}{R_{g}}}\right).}

Finally, we have the following closed-loop gain (applicable only to the above circuit)

{\displaystyle A_{\text{CL}}={\frac {V_{\text{out}}}{V_{\text{in}}}}=1+{\frac {R_{f}}{R_{g}}}.}

High frequency characteristics

The gains and formulas above are only applicable for low frequency circuits. In high frequencies, the following will happen:

Above certain frequencies, voltage gain and current gain factors become diminished in inverse proportion to frequency increase.

The output signal becomes lagged behind the input signal (phase shifting) as the op-amp cannot react fast enough to the frequency changes.

Very high input amplitude (peak-to-peak voltage swing of electrical signal) causes distortions and the higher the frequency, the lower this upper amplitude threshold is (distortion appears at lower amplitudes at high frequencies).

Cut-off frequency is the frequency at which the voltage gain is 1/sqrt(2) of the low frequency gain, meaning, the power at the output is effectively halved in voltage follower setup. The cut-off frequency is unique to each op-amp component. It can be easier determined using an oscilloscope as the frequency at which the phase shift is 180o.

Textbook definition:

The frequency where the voltage falls to 0.707 of its intended value is the cutoff or -3 dB frequency, fc. (Gain in decibels = 20∙log(0.707) = -3dB.)

As a result of these special high frequency characteristics, op-amps can be unsuitable for high frequency applications.

Read more

https://en.wikipedia.org/wiki/Operational_amplifier

http://www.learningaboutelectronics.com/Articles/Voltage-follower

http://www.ecircuitcenter.com/Circuits/op_bandwidth1/op_bandwidth1.htm

https://www.researchgate.net/post/Please_tell_me_Why_the_cutoff_frequency_is_taken_for_3dB_and_not_other_values_like_1_or_2_db

Short story: “Lawyer”, “A.I.”, “Wikipedia”

Percy was about to throw the papers in the bin when he got a follow-up call from the seventy-two year-old plutocrat who owned these papers. He was warned not to take the proposal lightly, whereupon he explained the difficulty to not take these papers lightly. Following a long, two-hour dialogue, the man convinced the mayor to give the proposal a chance.

The man, named Gladstone, had been his donor for a long time. Percy met this person at a fund raising party in Alphen des Meer. At the time, Gladstone donned a dark charcoal suit with a business card in hand. A deep pink cravat with a few horizontal white stripes near the end folded under his jacket. The cravat, he later admitted, was a calculated red herring and not by personal taste.

That evening in Alphen des Meer, he asked the-then-candidate a question that led to these papers lying on the-now-mayor’s mahogany desk.

“Tell me, Mr. Percival, what drives you?”

“Pardon me?”

“No, pardon me, perhaps I shouldn’t have asked?”

“Ah, no, I’m a bit surprised. That’s all. Can I choose more than one?”

“As many as you like.”

“Then it is fame, fortune and power.”

“Interesting…why is that?”

“I won’t lie, Mr. Gladstone. Personal gains and personal stakes are incredible motivators. Those who have them tend to invest more in the position than those who are in for the novelty of it. While corruption is certainly a possibility, I still prefer a sharp knife even if it can kill me.”

“I see you have no fear of political correctness, Mr. Percival. As a businessman, I appreciate men who can articulate exactly what they want. Perhaps, you can elaborate more on what is it that you want to accomplish with fame, fortune and power?”

“Haha, that I’m afraid I cannot disclose…”

The man behind the proposal, the Autonomous Automobile and Public Transport Reform, was a sharp knife that could kill him.

The papers highlighted policy changes necessary to accommodate a displacement of all drivers and truckers in the city. They are to be replaced with self-driving vehicles, robot chauffeurs who can speed through intersections without slowing down, weaving between fast-moving streams of other robot chauffeurs, coordinating with every other vehicles in the local swarm as one entity.

Employment safeguards must be abandoned for all concerned professions, mandatory upgrades and recalls of old car and truck models must be enforced, traffic lights must be dismantled, road signs must be scrapped, and magnetic lanes for new dedicated autonomous zones must be painted. It would take the city many times its discretionary budget to enact the proposal. The numbers on the financial statements attached to the papers almost gave Percy a heart attack. He had to check his smartphone to make sure it was not April’s Fool.

But Gladstone was adamant to get the proposal passed.

He owned a conglomerate named Gladstone Three in Dubai. Other than his pink cravat, his other defining characteristic was the immeasurable wealth from oil drilling and venture capital investments in the Middle East and East Asia. He invested heavily in self-driving technology and put himself in the position where he could claim monopoly as soon as the technology was adopted.

The man got right to the point when he was invited to speak in front of Liston’s budget office. He agreed to shoulder the bill; everything from the manpower to the compensation for laid-off drivers; on one condition: that he must be granted a monopoly in self-driving technology.

The budget office accepted his demand.

On the day a draft of the proposal was submitted to the mayor’s advisory committee on judiciary, Gladstone invited Percy to his office on Twelfth Avenue where he threw a small party on the thirty-fifth floor of La Seraphica tower. It was then that the mayor learned the plutocrat had a son. He had a crippled son; blond haired, about Percy’s age, wearing indoor sunglasses, and bound to a sophisticated wheelchair.

“Thank you for always helping my father, Mayor Percy. I heard you were a lawyer before you were a mayor. I too was a lawyer until I took a car in the knee. Now I have wheels for legs.”

“You have become an earth dragon, Dovahkiin.”

“This is the best response I have ever gotten.”

“I’m glad you like it, Gladstone Jr.–”

“You can call me Lancaster, or Lance for short. It’s a pleasure talking to you, Mayor Percy, but I’m afraid it’s time to change my I.V. drip.”

“Alright, I’ll see you around then.”

Back when Lance was a law student, a professor once asked him a peculiar question: When a chair is used as a murder weapon, who owns the responsibility for the crime; the manufacturer, the vendor, the user or the victim? And, without a moment of hesitation, he answered:

“The user is responsible, of course. Can you blame the manufacturer?”

“For the misuse of their product? No, I don’t think so. But for criminal negligence? Yes, it is possible.”

Percy heard this story from Mr. Gladstone when they talked on the phone a week later. At the time, the draft hit a roadblock in the mayor’s advisory committee on the judiciary. Newspaper began to cover the draft and with public awareness came public outcries. Thereafter, in a Tuesday morning, the mayor paid the courthouse a visit where he was greeted by a group of protesters.

As soon as his car arrived in front of the courthouse, five plainclothes bodyguards cleared a path through the crowd and stopped reporters who were flashing cameras and pointing microphones over the men’s shoulders, asking questions about the controversial transport reform, from coming closer.

Upon entering the courthouse, he made a phone call. There was a priority lane for the mayor and his escorts at the security screening which led to a two-story atrium where the info desk situated. He nodded to the clerks as the group walked by and onto an escalator to second floor.

In one of the courtrooms on the second floor, a judge accompanied by a police officer were waiting for the mayor. The mayor’s bodyguards hung around public waiting area while the mayor followed the judge through a restricted corridor to a cramped chamber. It was in that cramped space that he came face-to-face with two opponents of the draft.

Gladstone was calm when he learned of this meeting. “So, how did it go?” he asked.

“Have you ever heard of the backfire effect?”

“I believe I have. Let’s see…the backfire effect is a name for the finding that, given evidence against their beliefs, people can reject the evidence and believe even more strongly.”

“Heh, Wikipedia”, Percy mused.

“Indeed, it’s Wikipedia. I’m surprised you knew.”

“I have a friend who collects retro stuffs. Once he borrowed my money to buy a SSD with Wikipedia fork from ‘012 and it had been in my possession for a few months.”

“Now that’s some ancient stuffs no doubt.”

“Aye. The talk didn’t go well as you might have guessed. You see, nobody wants to lose his job to a robot and nobody wants to be run over by a hacked car. No amount of compensation will change their minds on that.”

“Ah, resistance to change, humans are truly the same everywhere.”

“On that later point, true irony is…I got death threats, actual death threats in my inbox this morning–”

As Percy broke the news, the plutocrat’s hand clenched into a fist. Percy saw the man’s eyebrows stiffened; the expression of anger and not fear. The smirk on his lips curled wider as he continued:

“–At the end of the day, they are still fighting for the exclusive right to kill their fellow men. A hundred roadkills by human will never cause the outrage a single roadkill by robot will.”

“Is that discrimination?” an unexpected remark came.

Both men cast their glances at the source of the remark. There they saw Lancaster on his wheelchair approaching. Gladstone stood up, intending to help, but the lad turned down the gesture:

“It’s okay. I can manage this.”

“Hmm? What happened to your follower, Dovahkiin?”

The last time Percy saw the man, there had been a maid pushing his wheelchair and tending to his every need. The maid was not present this time.

With a light chuckle, the young master answered:

“I sent her on some errands, namely, picking up the supplies my physician is requesting for the quarterly examination. I saw on the news that you visited the courthouse today.  From what I heard, there was a big protest outside the courthouse. What is it about?”

“Oh that! Just some inept soon-to-be-unemployed stirring troubles instead of working toward their inevitable retirement, or learning new skills for an occupational change…”

“Is it alright to speak about your constituents with such disdains?”

“I’m a lame duck, after all. This is my third term and I can’t run for office in Spring election next year. The amount of damn I give to them is about this much.”

He made a gesture with his index finger and his thumb. He quantified his care for his own public image at this point the size of peanut.

“Isn’t it more problematic for you to pass new regulations then?”

“Exactly why I have to give some people a good smacking and remind them there’s a hard winter ahead for the unemployed. Elected officials are easier to deal with when the talk starts with the threat of losing your father’s donation. Peer pressure takes care of the rest.”

“Although, of course, some people are still beyond my influences”, Gladstone interjected.

“Ah yes…the judges, how can I forget? They are always so rigid when it comes to new laws.”

“Now that I think about it. How do you normally get them to agree? They can’t be bribed, can’t be coerced and can’t be forced out. Such a pain in the ass they are…”

“Normally, you need to amend the bill until it meets their moral and whatever standards. Nine of them accepted the trade-offs we proposed, two of them, however, wanted the cake and ate it too. How can one eliminate human errors without first eliminating human factors from the equation?”

“Is there a way to overrule these judges?”

“Good question. There isn’t.”

“Say, if they, by chance, got caught up in an unfortunate incident and were unable to serve the office then could you perhaps appoint new judges who are more…agreeable?”

“Ah, perhaps an accident by human error”, Lancaster mused.

“Hold it. What are you suggesting?”

“It’s a decent trade-off, don’t you think? Two judges for a bill that can save hundreds a year. Or perhaps, are you in any way a cake-eater like them?”

“Is that a threat, Mr. Gladstone?”

“Oh, no, no, no”, the man smiled devilishly, “Not at all! How can I threaten a friend whose inbox is already filled with threats from the other side?”

“Mr. Gladstone, sometimes, even a politician will appreciate someone who can articulate exactly what he wants. But I digress, there is no point in reiterating what both sides already understood.”

“You are surprisingly calm. Do mayors get threats like these often?” Lancaster asked, a flash of admiration glinted in his eyes.

“Not at all. I’m normally the one making the threats.”

“And so am I”, Gladstone nodded.

But neither of them exercised their coercive might, both understood there was a line that should never be crossed. The dinner they shared on the thirty-fifth floor of La Seraphica tower that day started a crack in their relationship and the crack only got wider as the judiciary committee continued blocking the reform.

Then the unthinkable happened.

The truck that had his name written on its bumper plowed into the silver eight-seater carrying Gladstone on his way back from the state court. The eventuality he had been desperately trying to avert struck him back with a vengeance. That Wednesday night in August, the wealthy businessman shed his last breath on the cold asphalt of Twelfth Avenue. No one in either vehicles survive the crash but it was determined to be caused by human errors.

His funeral was attended by legislators, business partners and all eleven members of the judiciary committee; whereupon they pledged to make his final dream come true. His son, Lancaster, was not seen at the funeral but the maid escorting Lancaster was there. She apologized on her master’s behalf for the absence, stating his health had taken a turn for the worst. She did not say anything else and Percy knew better than to press the matter.

In the end, the reform never came to pass. Even with the approval of both the Council and the Court, the funding necessary for the bill was rescinded by Gladstone Three. It became clear that with Gladstone father and son out of the way, the new president had no reason to follow through with their promises. One moment of hesitation and the greatest gift Liston had ever received slipped between their fingers.

One morning in February, when the winter cold still lingered in the air and when Percy’s days as this town’s mayor had come to an end, he caught glimpse of a familiar deep pink cravat with a few horizontal white stripes, in a silver eight-seater parked across the street from his private residence. He rushed to the front yard, a smile flashed across his face.

The car was still there, parked across the street by the sidewalk. Its passenger door swung open and his demeanor darkened as he remembered Gladstone had passed away. A petite, Asian girl in familiar dark charcoal jacket and a strange, white checkered skirt stepped out and politely bowed to him. It was not the same deep pink cravat she wore but a necktie of the same design.

“Greetings, Mr. Percival. The name is Gladstone. Have you accomplished what you desired with fame, fortune and power?”

“Wh-What is the meaning of this?”

“We are closing down Liston office today and I’m here to fulfill the previous Gladstone’s final directive. So, I’ll ask again. Have you accomplished–”

“No…”

“Excuse me?”

“When he asked me this question nine years ago. I lied. There was no secret to disclose. I had nothing I wanted to accomplish. Fame, fortune and power were what I wanted to accomplish and I did accomplish them.”

“I see…”

“However”, he cleared his throat and continued, “He made me realized fame, fortune and power are not the end. They are the means to the end. Only when I lost everything that I learned what my goals are.”

“And they are…?”

“I want to correct political correctness, Ms. Gladstone. With his life, he proved it can be done. He proved that bipartisan agreements can be accomplished. I want to realize this agreement and make his vision a reality. I will run for office again in three years’ time. Will you continue to support me?”

After a moment of surprise, she grinned and removed her necktie, along with an earbud from her left ear. Placing both items in his hands, she bowed her head again and solemnly informed:

“Welcome back, Mr. Gladstone.”

Saturday Night Out #1

About this writing prompt

See: Character-Driven Fiction Writing Prompts

Saturday Night Out is a character development prompt for White Destiny. The prompt will feature characters from the novel in casual daily conversations that explore the personalities and world views of these characters. The prompt’s name is inspired by the following cheer between the Baron and the red helm knights from revision 2, chapter 4:

“…Ha’lly willy boos! Tonight is Saturday night. Who stays home on Saturday night?”

“Dead people!” the knights answered in unison and threw their fists in the air.

“What was that again? I can’t hear you”

“Only dead people stay home on Saturday night!” they shouted again.

These short prompts will consist of only dialogues.

~ ~ * ~ ~

The lazy master and a good friend

“Sir Richard is going to revoke my funding next week. That is, if I were to remain a lazy master.”

“A lazy master?”

“One that fails to meet his daily quota.”

“Which daily quota? Oh, you mean that daily quota. Isn’t it really simple though? It only took me two moons to finish mine.”

“I envy you.”

“Yup, I know I’m the best.”

“Clevandi finished his before getting the quarter though.”

“…”

“I have no idea he had a quarter…or that he had a daily quota.”

“He has neither.”

“That doesn’t count. I’m still the best.”

“Growing arrogant aren’t you?”

“Heck yes, I am a master now. I earned the right to brag…Don’t tell anyone I said that okay?”

“What is in it for me?”

“I’ll buy you ale.”

“These lips are sealed. So, what will you buy for my hands?”

“Your hands?”

“I can still write about this, you know?”

“…”

“Go work on your daily quota.”

“Touché.”

“Wait, I’ve just realized something. If Clevandi doesn’t have a quarter, he technically cannot finish his quota before getting his quarter.”

“Don’t sweat the details. It is the point that counts.”

“Sure, Leo. Don’t sweat the details. Remind me of the time you told me “chicks love Silverflow masters”. The only “chick” I have seen so far is an old rooster named Annabel and she is…I don’t know where to start….”

“Apologize to the whole rooster-kind now.”

“I kneel.”

“I kneel as well.”

“The worst part of this is…I think she actually fancies me…”

“You two will make a great pair, Sleeping Beauty.”

“You’re giving me goose bumps…”

“Weren’t you really popular before, though? I sometimes see you with that daughter of…eh, the butcher, I think?”

“Her father is a potter. A cutie except she thinks I’m one of her girlfriends crossed a mule. Unless…you were talking about the butcher’s wife, then it’s not me she wanted, it’s Alex.”

“Alex…”

“Yep. I’m just a “good friend” to them.”

“That’s luxury. I’m not even a friend with one.”

“What about Katherine? Weren’t you guys like…really chummy back then?”

“Is this jealousy am I sensing?”

“…”

“No.”

“Rest assured. She’s not my type. I like someone smart; preferably a master of Silverflow but not necessarily, a candidate or apprentice will do just fine. Being able to hold a logical argument is the prerequisite and, she must not be an old rooster named Annabel.”

“Apologize to all roosters now!”

“I kneel.”

“You’d better be. Although…isn’t that Princess Lilia you’re describing?”

“Too young. I’m turning forty next year and she’s turning twenty next week. Frankly, I feel old looking at her. Just imagine what she can achieve in twenty-year time. What right to I have to be a part of her destiny?”

“Ah…yeah…I can see your point.”

“Sometimes, it does feel like I’m holding her back more than anything. But, what can I do? I cannot quit. What price does Leonardo di Price have without his influences?”

“Is influence why you pushed for the secession?”

“…”

“No, I want that from the start. All else are means and justifications.”

 

Short story: “Rain”, “Bottle”, “Bookstore”

A mother and her young son sought refuge from a sudden rain in the bookstore I worked in. They were not the only ones pulled from the busy torrent of city life by the weather. Half a dozen others were standing at the porch, a few drenched to the sole of their feet; all looking miserable, eyes gazed at the darkened clouds and the slow-moving street of even more miserable humans, slopping through knee-deep water.

The young boy, about seven years of age, was exhilarated. His eyes sparkled. His head turned left and right to survey colorful rows of books. He left the mother at the entrance and dashed to the kid’s toys section.

His mother, looking exhausted from a day’s work, walked slowly between “Foreign literature” and “Politics and History” isles. She cast an empty gaze, fixated at shoulder-level, at the bookshelves. At times, she would pause to catch a quick glimpse at a rusty bike she parked in front of the store and then at the other end of the story where her son was supposed to be.

The rain outside intensified.

A coworker adjusted the air conditioner and turned on the light. It was only five in the afternoon and the storm cloud already made it seemed like seven. In the store, we always kept the air dry and cold. The fluorescent white light was replaced with natural lighting at night; though not as pleasant to the reading eyes as daylight, it gave a modern, almost sanitary feel that was, supposedly, attractive to young adults.

And on that dark-blue-and-white, sharp-edged canvas smacked dab the smeared and soaked wet passersby who were not here for the literature, but here for the roof. Rich people had cars, middle income rode motorbikes home wearing composite ponchos, only those whose shabby nylon ponchos could not protect them from heavy rain and those who forgot to bring ponchos gathered here.

“Books sell like hotcakes in this weather, don’t they?” an office lady remarked as she put a few cookbooks and two desktop ornaments on the cashier. She was among those who forgot. Not quite. While there were more people in the store when it rained than when it didn’t, not all were potential customers, only a small portion was.

I smiled out of courtesy and made no comment, quietly scanning the bar codes of her purchase.

“They are presents”, she said holding up the ornaments side-by-side. The ornaments, two ceramic, pawn-sized statues of a boy and a girl hold two halves of the word “LOVE” were a matching pair. “Aren’t they cute?” she cheerfully asked.

“Is that so? Do you want me to wrap them, ma’am?” I asked.

“Do you take credit card?”

“Yes, here”, I answered and showed her the card reader. I assumed that was a no for gift wrapping so I started putting the items in common plastic bags. It was then that I took note of loud scolding at the end of kid’s toys section.

It was the boy from before and his mother. She smacked his hands repetitively and hurled curses at him. The boy began to sob and then cried aloud. She hit him even harder, ordering him to stop crying. She slapped his face several times, making loud smacks every time, and with that she finally stopped his cry.

My coworker came near with a dustpan and a broomstick. The woman bowed her head apologetically and asked for the dustpan and broomstick from my colleague. She insisted, forcefully taking the broom and then starting to sweep shards of glasses in the dustpan. I caught glimpse of the outline of a broken glass bottle as the coworker picked up the largest fragment and took a look at the price tag.

With just that one glimpse, I could already imagine what was going on.

“Where do I sign?” the office lady urged. I was sure she also saw the scene but chose to mind her own business.

“Sign here, ma’am. Thank you for your patron. Please come again.”

Though, she would not be going anywhere in this weather.

The coworker brought the price tag to the cashier. The broken ornament was a miniature ship-in-a-bottle, an expensive one at that.

“I’m scared. I’m…so scared. I have never seen a mother like her before”, she confessed in shaking tone.

“I have but it is beyond my jurisdiction to obstruct their right”, I said.

Truth is, I would like to. But, all of us lived in a culture where parents owned the exclusive right to educate their children in however manner they wanted; however cruel they might seem to Westerners. It was also in this culture that we grew numb to the suffering of those around us.

The boy nervously approached the cashier, weeping in suppressed hiccups. His mother loomed behind him. She had this angry and worrisome expression as she drew a small nylon wrapped roll of crumpled cash from her pocket.

“Pardon me, madam, sir. But…this is all I have…for today”, she said.

From her hesitation, I realized it must have been difficult for her to lay the little money she had on her in front of us. That realization brought great awkwardness to both me and my coworker.

“I’ll bring the rest of the money tomorrow…and the day after”, she pleaded.

My coworker winced.

The young boy froze, his breaths hastened and so did his hiccups. He understood what was happening, didn’t he? He must have.

“Excuse me, I would like to pay for these too”, the office lady from before returned to the cashier with more books. Language learning and art books for the young man who was then with her.

From her conversations with this young man in his twenty, he must have been the office lady’s son. They indulged in idle chatters, about Franz Kafka’s memoir, about the magnum opus “No Longer Human” of Dazai Osamu on display at the highlight section near the entrance.

The weeping boy looked at the office lady and his son. His hiccups got louder and faster.

“Shut up”, his mother gave him a slap. He clammed up and shriveled.

This time, I was sure the office lady had noticed this woman who was so cruel to a kid. The lady’s expression barely changed, her gaze paused on the boy for a moment, but soon broke off and resumed the chatter with her son. The young man paid no attention to other people, seemingly in deep debate whether to purchase yet another classic book–Shouwa Anthology–now or order it later for online retail discount.

“I can’t watch this anymore”, my coworker said, discreetly gesturing toward the abusive mother, “You deal with her, okay?”

Then, she turned to the office lady and moved her books to another counter, informing: “This way, madam. Sorry for the wait. Do you have a coupon?…”

And so, I was left alone with the penniless mother and her weeping son.

“Dis-discount! Can you give me a discount?”

“This is a bookstore, not a flea market. We don’t bargain here”, I said.

She let out a long sigh.

Hesitantly, I looked through the coupons in my drawer. There was a glimmer of hope, expectant daze in her eyes for a moment as I did so. But, I found nothing of such natures. I shook my head and she let out another sigh. After that, she turned to her son.

“Look at what you have done, you son of a bitch. You’re just like your useless father”, she screeched and started beating her son again in front of everyone.

I noticed the office lady was watching in great discomfort. Her son had left to buy a cheap rain poncho from a nearby store. When he returned, the lady urged him to go home despite the rain continuing to pellet the windshield of cars on the street. They left in haste as though running away from a natural disaster.

My coworker also retreated to the end of toys section. No one wanted to have anything to do with this terrible woman. At this point, I too could stop pretending to be sympathetic. I was getting tired of her treatment toward her own son.

“Is that your bike?” I asked, pointing to the bike parked at the porch; the only one that was there, possibly because she did not want to pay the parking fee. “I’m afraid we’ll have to seize it until this–I motioned to the broken item–is fully compensated”, so I said.

Indeed this didn’t feel right. It felt terrible taking money from this woman. But, it was either her day’s worth of work, perhaps many days’ worth of work, or my shift’s worth of work.

“No!”

She snatched the money on the cashier and burst out onto the porch.

“Stop her!” I shouted.

But, despite the flood and the traffic, the woman was gone as soon as I got to the door. She disappeared into the rain like a phantom, leaving only the young boy behind as proof of her existence.

The boy waited alone till the bookstore’s closing hours. His mother did not return for him and his cry drew attention from passersby. As expected, these people were aware of the situation. After the woman ran away, they began to discuss openly about her abusive behavior. They comforted the boy, they gave him food and talked to him.

We turned the boy to the police along with the security footage of his deserted mother. I thought that would be the end of it. Yet, early in the morning of the next day that I received a phone call from the bookstore. It was not on the clock that day.

“Hello? There’s a crazy woman here asking about her son. Do you know anything about her?”

“…”

I was speechless.

“Tell her she doesn’t deserve to be a parent.”

“Wait! I have the money here. All of it. The money…”

“That is not the problem, is it?” I said.

“My baby girl…she was starving last night. I needed to get home and feed her. I couldn’t afford to walk. I know I don’t deserve to be a mother but…Look, I sold my bike, I have the money now. I want my son back. My children are all I have left…”

I could not speak. The words did not come out.

“Hello?”

“Stay right there, I’m coming”, I told her and hang up.

At the porch, she was waiting. In her arms was a baby wrapped in rags. She held the money in her hand, the same hand that pressed her daughter into a tender embrace. Her body swayed in the chilling morning breeze, her head rocked up and down as her bagged eyes fought off drowsiness.

“Hey!” I tapped her shoulder to wake her up.

“My son! Where is he? Here’s the money, take it! Take it!”

“Calm down. Listen to me. Listen…”

“How can I calm down? Where’s my son? I want him back”, she cried.

The baby was waken up and started crying loudly.

“Shut up, shut up, you little bitch!” she shouted at the baby, shaking up and down violently.

“Stop it!” I gripped her arms and forcefully stopped the shaking, “They are your flesh and blood! Why are you treating your children like that?”

“That’s none of your business!” she snapped.

I gritted my teeth, “Then you have no right to know where your son is”, I said.

She gasps for air, then a few mournful hics and finally lowered her head.

I let out a long sigh.

Her husband was a big better on cockfighting. Whenever his cock lost a fight, he would go home and beat her up out of spite. Whenever his cock won a fight, he would go out drinking with his buddies till he ran out of money and then he would go home at three in the morning to beat her up. When he was drunk, he would try to kill his own children as well.

“I prefer him losing…if so, he would spare my son and daughter”, she confided.

“You should call the police when that happens…”

“I don’t have money to bribe the police”, she cracked a bitter smile, “I tried that”, she added.

I sighed again. Then, I took from my wallet a large sum of money and a business card.

“You have money now, and a lawyer”, I extended the items to her.

“I can’t take your money. You worked hard for it.”

“This is not my money”, I paused to consider my wording a bit, “This is your son’s money”.

“Eh?”

“After you ran away yesterday, some people in the bookstore donated food and money to help him. They already paid the compensation in full and this is merely the surplus. Your son is at the police station. You can have this money on one condition: that you will take good care of your children from now on.”

“I-I will. Of course, of course I will!”

I shoved the money into her hand, wrapped her fingers around it and parted ways with these last words:

“I know you will.”