Showing posts with label general. Show all posts
Showing posts with label general. Show all posts

Sunday, February 7, 2021

Enclosure ideas for WiFiChron and other clocks

It turns out that most electronics, even prototypes, can be easily enclosed with Lego. And that means no screws, no glue, no fasteners, zero tools, just the bricks and some imagination.

This is the HDSP clock variant with 1" displays driven by HT16K33 (introduced here). The board was cut and filed (0.5mm on each side) to fit snug between the walls (see this).


Next is a HDSP clock variant with two Adafruit Quad Alphanumeric displays.


Similarly, the PCB was cut and filed a bit. The assembly fits solidly between the bricks (no movement when shaken). As in the previous build, the exposed PCB is kind-of-required to allow access to the two buttons (set hours, set minutes).

Both of the above can be mounted on a Lego wall (as found in schools) or they can desk-stand on their own.

Here is an example of a Lego-encapsulated WifiChron.


The PCB was also filed about 0.5mm on each side to fit between the lateral brick walls. It did not have to be fastened in any other way. The ESP8266 module fits inside nicely. The 3 buttons and the USB mini B connector are all easily accessible from the back.

Below is the Lego version of the Axiris clock.



Since it does not have any buttons, the time is set through Bluetooth (command "SET TIME=hh:mm", sent from Terminal app while BT paired).

And finally, a couple of OLED clocks, both running the same software on similar hardware: pro-mini + OLED shield and wsduino + 2.42" OLED shield, respectively.



Note that this is the prototype version, using a LiPo battery with charger (similar to the one shown here).


Again, all the above enclosures feel solid: nothing moves or rattles when upside down or even shaken. I did not try dropping them though :)

And lastly, the WiFiChron with Adafruit quad 0.56" displays from the previous post, sandwiched between scrap plexiglass plates:




Saturday, March 21, 2020

Teaching Electronics to Kids

My "Introduction to Practical Electronics for Children" course concluded successfully a few weeks back, before March break. Now, with schools closed for covid19, it would be a good time for the kids to practice soldering and learn by doing. At this stage, I think it is easy to expand their knowledge and skills in the field of electronics just by assembling kits.

Here are a few notes and observations from my teaching.
  • Each class had 6 groups of 3 students sharing a soldering station. This (not my decision) was probably based of space constraints (6 desks in a normal-sized classroom) and safety/supervision considerations. It worked pretty well: the 2 students (in each group) not soldering had time to observe, analyze, think and to ask lots of questions. Two professional teachers assisted, with supervision, helping the students and keeping discipline.
  • Each student had their own "HDSP clock" kit to assemble. It took 6 one-hour sessions to complete, with a success rate of about 95% (2 failures out of 38 assembled, because of solder bridges).
  • The intended "50% theory and 50% practice" ratio had quickly become 10/90. Still managed to introduce components (resistor, capacitor, crystal), electrical concepts (AC vs DC, voltage, resistance, current, frequency) and units of measures (Volts, Farads, Ohms, Hertz). We even talked about Tesla batteries :)
  • Some parts were lost (e.g. crystal) or damaged (dropped, then stepped on by accident) between or during the classes. The lesson learned is to have extras available.
  • Each student received individual instructions, guidance, assistance and supervision on soldering. We came up with the "3-second rule" to make a good soldering joint: hold the tip of the soldering iron in contact with the pad and the terminal for 3 seconds while touching and melting the solder wire on the tip.
  • Having students pay attention to the instructions was very important. It saves energy to talk once to the whole class, rather than answering the same question to each individual. (I also learned from professional teachers  the "1-2-3 eyes on me" attention-getter.)
  • Sockets for integrated circuits are a must in a beginner kit. Imagine fixing an IC soldered in the wrong orientation! (The "worst" that happened was that all 3 ICs in the kit were soldered directly onto the board, luckily in the correct orientation.) Also, silkscreen should be as detailed as possible, indicating the component's place. In case of the "HDSP clock" kit, the students were able to easily identify the placeholders for each component, just by using logic (except for the resistors; they learned quickly to bend the resistors' terminals).
  • Some of the most frequent mistakes were soldering bridges and filling empty holes with solder. Bridges were easily fixed (initially by me, then the students learned to do it themselves) using the copper wick/braid, and flux. To fix the solder-filled holes, I had to use a tailor pin (part of my EDC Swiss card).
  • Surprisingly, every student showed interest in working on, and completing, the kit. I think it was a successful experiment even for the school, in making "practical electronics" as part of their curriculum. Like in the old days of practical skills teaching (wood working for boys, sewing or cooking for girls), this course demonstrated that Grade 6 students are very capable and eager to acquire skills that may stay with them for life.

Sunday, March 15, 2020

Teardown of an Old Dimmer Switch

The 40+ year-old dimmer (made by Nortron Industries Limited in Milton, Ontario) in my attic broke down. Electronically, the dimming circuit still worked, but mechanically, the push button got stuck.
This is what's inside, for the curious.



The active component in the circuit is Q2006LT, a "quadrac" which, according to the datasheet, "is an internally triggered Triac designed for AC switching and phase control applications. It is a Triac and DIAC in a single package, which saves user expense by eliminating the need for separate Triac and DIAC components".

The "reversed-engineered" schematic looks like this:


For those who want to understand more on how the triac-controlled dimmer works, this article provides an in-depth explanation.

The 250V capacitors may be reused in a Nixie high-voltage (~170V) power source. For a hoarder, both the choke and the potentiometer (push button removed) look good.

I will report back on the internals of the replacement switch in 40 years or so, when it breaks down. I hope I/it last(s) that long.

Sunday, February 2, 2020

Introduction to practical electronics for children

I designed this 7-hour (one hour/day) course for 6 graders, as part of their STEM curriculum.
The goal is to introduce the children to practical electronics and teach them about:

1. electronic parts/components: how to identify/recognize them, how to measure (using a multi-meter), what they are used for (role in an electronic circuit):
  • resistors (current reduction), variable resistor/potentiometer, trimmer
  • capacitors (energy accumulator), variable capacitor
  • transistors (amplification)
  • coils (inductors)
  • diodes, LEDs
  • speakers. microphones
  • buttons, switches
  • integrated circuits, processors
  • displays
  • sensors (light, magnetic, proximity/infrared/ultrasound)
  • servo motors
  • relays
2. how to solder (using a soldering station), how to place and position parts on a board, how to check connection, how to follow steps of an instruction manual;

3. electricity and electronics concept:
  • voltage, current, resistance;
  • AC vs DC
  • digital vs analog
  • oscillation
  • rectification
  • amplification
  • series, parallel
  • voltage transformation (AC)
  • voltage regulation (AC, DC)
4. basic understanding/reading of schematics (wiring, electrical connections).


Required materials

Course schedule

Day 1
theory: introduction to components; presentation and identification (1/2 hour)
practice: beginning soldering (1/2 hour) LED + resistor, using flux, soldering wire, wick, on prototype PCBs;

Day 2
theory: introduction of a simple clock kit or another, more familiar to me, simple HDSP clock kit; assembly analysis, component placement and positioning;
practice: solder passive components on PCB; assemble the HDSP clock;

Day 3
theory: more on components; introduction to schematics;
practice: solder the active components of the clock kit;

Day 4
theory: electricity concepts (digital vs analog);
practice: finishing up the kit assembly; power, test, use;

Day 5
theory: electricity concepts (voltage, current, resistance); example of other kits;
practice: learn to use an ohm/volt/meter;

Day 6
theory: electronics concepts (oscillation, rectification, amplification, sound generation etc.);
practice: bring an electronic toy, working or not; disassembly, analysis, repair (if needed);

Day 7
practice: continuation from Day 6; identification of components used in the toy; understanding of how it works; modding/expanding functionality/adding LEDs, speaker, buttons etc.;


We are already on "Day 3", but behind schedule. Soldering is harder for the kids than I originally thought. One thing that I overlooked was that each student needs individual attention/supervision on the practical side (soldering, component placement etc.). Half hour per day of hands-on practice is definitely too short at this level. The schedule may be a little aggressive for the average Grade 6, probably better suited for older and more disciplined students. In any case, I am working on adjusting the content of the course and the feedback I receive is amazing. Kids really enjoy the fact that it is practical and some of them are amazed when they see the LEDs they soldered actually lighting up.


Tuesday, April 26, 2016

From the mailbox

AlexP managed to port the Wise Clock 4 code to Arduino Mega2560 (shared here, thanks Alex!). He made this video demonstrating it in action:


Today I had a great day! I did it! I soldered a development board for my Mega2560. A little corrected code and ... voila!  Wiring diagram:
  • rtc sqw (1hz) - pin 2
  • menu key - pin 3
  • set key - pin 4
  • plus key - pin 5
  • speaker - pin 6
  • speaker - pin 7
  • HT1632_WRCLK - pin 10
  • HT1632_CS - pin 11
  • HT1632_DATA - pin 12
  • HT1632_CLK - pin 13
  • rtc sda - pin 20
  • rtc scl - pin 21
(SD while not tested, but I think it works)
  • sd miso - pin 50
  • sd mosi - pin 51
  • sd sck - pin 52
  • sd cs - pin 53

NelsonC built his own hand-wired version of WiFiChron and it looks awesome:



MikeM sent in (thanks Mike!) his latest WiFiChron code (available here).
The enclosed zip file compiles under Arduino 1.6.8, though it generates a warning I haven't figured out how to eliminate.
Ray ran into a problem with data overruns. When data in an RSS feed was split between multiple packets, sometimes the last few bytes of a packet were dropped from the RSS buffer. I didn't see that problem with my clock when I was developing the code, nor did I see it on the WiseClock4. I've re-built the RSS state machine to be more CPU efficient, and now the packets are processed without drops. We probably don't need to change the RSS code on the WiseClock4 as it runs at 16 MHz and not 8 MHz like the WiFiChron.
I also changed the PROGMEM statements to fit the 1.6.8 standard.

And finally, I got the PCBs for the 1284-equipped versions of WiFiChron and bGeigie nano.
For both I relied on internal (software-driven) pull-ups (basically I eliminated the pull-up resistors), without checking first if that would work. Unfortunately, the current sanguino library does not implement correctly the function pinMode(x,INPUT_PULLUP). So I had to resort to resistors soldered on the back of the board. That, plus missing a necessary decoupling capacitor, plus also missing some connections on the bGeigie board, made for a "fun-filled", but in the end successful, testing. More on these in a future post.

Saturday, January 23, 2016

Break

I was going to say that this was the typical case of work/life taking precedence over hobbies. Not a good excuse though, since one can always find bits and pieces of time, like coins between couch cushions :). The best explanation for the long break is probably laziness. But I didn't just loiter around. With my desk full of just-started or half-finished projects screaming for time and attention, how could I? Here are some of the things I re-visited and tried to complete.

1. The Axiris IV-3 clock
As designed by Axiris team, the enclosure for the IV-3 shield can only accommodate one Arduino. The only way to make a real (with RTC) clock is to replace the Arduino with a wdsuino. Then, there is the issue of buttons (or any other way to set the time without using a PC, through USB). I managed to add an extra board that holds two buttons, accessible through the holes on the bottom side of the enclosure.
Below are some pictures.






The sketch I used is included below (based on the sample code from Axiris).

#include "Wire.h"
#include "DS1307.h"

#define PIN_BTN_SETHOUR 13
#define PIN_BTN_SETMIN  12

// globals; their values are set in getTimeFromRTC();
int hour;
int minute;
int second = 0;
int year, month, day;

// receive commands from serial port in this buffer;
char cmdBuffer[30] = {0};
byte nCrtBufIndex = 0;

// read time from DS1307 at intervals; for 5000, that's about 6 times a second;
#define MAX_TIME_READING_COUNTER  5000
long timeReadingCounter = MAX_TIME_READING_COUNTER;

/*
       pin 2
        ---
 pin 7 |   | pin 3
       |   |
 pin 8  ---
       |   | pin 4
 pin 6 |   |
        --- . pin 9
       pin 5
*/

static  byte  digit_seg_data[12*7] PROGMEM =
{
/* pin    2     3     4     5     6     7     8  */
        HIGH, HIGH, HIGH, HIGH, HIGH, HIGH,  LOW,    // Digit 0
         LOW, HIGH, HIGH,  LOW,  LOW,  LOW,  LOW,    // Digit 1
        HIGH, HIGH,  LOW, HIGH, HIGH,  LOW, HIGH,    // Digit 2
        HIGH, HIGH, HIGH, HIGH,  LOW,  LOW, HIGH,    // Digit 3
         LOW, HIGH, HIGH,  LOW,  LOW, HIGH, HIGH,    // Digit 4
        HIGH,  LOW, HIGH, HIGH,  LOW, HIGH, HIGH,    // Digit 5
        HIGH,  LOW, HIGH, HIGH, HIGH, HIGH, HIGH,    // Digit 6
        HIGH, HIGH, HIGH,  LOW,  LOW,  LOW,  LOW,    // Digit 7
        HIGH, HIGH, HIGH, HIGH, HIGH, HIGH, HIGH,    // Digit 8
        HIGH, HIGH, HIGH, HIGH,  LOW, HIGH, HIGH,    // Digit 9
         LOW,  LOW,  LOW,  LOW,  LOW,  LOW, HIGH,     // Hyphen
         LOW,  LOW,  LOW,  LOW,  LOW,  LOW, LOW      // empty/not lit at all
};

typedef  struct  _TUBE
{
  byte    digit;      // 0..9
  byte    dot;        // HIGH or LOW
}
TUBE;

// Display state of the tubes (read-write): {digit, dot}
static  TUBE  tube_list[4] =
{
  { 10,  LOW },
  { 10,  LOW },
  { 10,  LOW },
  { 10,  LOW }
};

// Variables accessed at interrupt level
static  byte    cur_tube = 3;        // 0..3

ISR(TIMER1_COMPA_vect)
{
  const  byte  *digit_seg_p;
  byte          digit;
  byte          pin;

  // Clear pins as fast as possible
  PORTC &= ~0b00001111;  // Clear pin A[0..3]
  PORTD &= ~0b11111100;  // Clear pin 2..7
  PORTB &= ~0b00000011;  // Clear pin 8..9

  __builtin_avr_delay_cycles(8*40);  // 40 us (at 16 MHz)

  // Select the next tube
  cur_tube++;
  cur_tube %= 4;

  digit = tube_list[cur_tube].digit;
  digit_seg_p = digit_seg_data + 7*digit;
  for (pin = 2; pin < 9; pin++, digit_seg_p++)         digitalWrite(pin,pgm_read_byte(digit_seg_p));
  digitalWrite(pin,tube_list[cur_tube].dot);

  // Enable the current tube
  digitalWrite(A0+cur_tube,HIGH);
}

void  setup ()
{
  Serial.begin(9600);
  pinMode(A0,OUTPUT);
  pinMode(A1,OUTPUT);
  pinMode(A2,OUTPUT);
  pinMode(A3,OUTPUT);
  pinMode(2,OUTPUT);
  pinMode(3,OUTPUT);
  pinMode(4,OUTPUT);
  pinMode(5,OUTPUT);
  pinMode(6,OUTPUT);
  pinMode(7,OUTPUT);
  pinMode(8,OUTPUT);
  pinMode(9,OUTPUT);
  pinMode(10,OUTPUT);

  // Turn on the LEDs
  digitalWrite(10,HIGH);

// (fc) filaments, for my special case; normally this is not needed;
  pinMode(11,OUTPUT);
// power the filaments;
  analogWrite(11, 200);

  // set-time buttons;
  pinMode(12, INPUT_PULLUP);
  pinMode(13, INPUT_PULLUP);

  cli();

  // We've observed on Arduino IDE 1.5.8 that TCCR1A is non-zero at this point. 
  // So let's play safe and write all relevant timer registers.
  TCCR1A = 0b00000000;

// (fc) half the number for 8MHz Arduino
//  OCR1A  = 250-1;       // 250 Hz (62500/250)
  OCR1A  = 125-1;       // 250 Hz (62500/250)

  TCNT1  = 0;
  TIMSK1 = 0b00000010;
  TIFR1  = 0b00000000;
  TCCR1B = 0b00001100;  // Enable timer

  sei();
}

void loop()
{
  checkButtons();
  
  timeReadingCounter++;
  if (timeReadingCounter > MAX_TIME_READING_COUNTER)
  {
    getTimeFromRTC();
    display_time();

    timeReadingCounter = 0;
  }
}

static void display_time()
{
  unsigned long   ms = millis() % 1000;
  boolean        dot = (ms < 500) ? HIGH : LOW;
  byte            u;

  cli();
  u = hour;
  tube_list[1].digit = (u % 10);
  tube_list[1].dot = dot;

  tube_list[0].digit = ((u/10) ? u/10 : 11);
  tube_list[0].dot = LOW;

  u = minute;

  tube_list[3].digit = (u % 10);
  tube_list[3].dot = LOW;

  tube_list[2].digit = (u / 10);
  tube_list[2].dot = LOW;

  sei();
}

void getTimeFromRTC()
{
  int rtc[7];
  RTC_DS1307.get(rtc, true);

  // check to avoid glitches;
  if (rtc[DS1307_MIN] < 60 && rtc[DS1307_HR] < 24 && rtc[DS1307_SEC] < 60)
  {
    second = rtc[DS1307_SEC];
    minute = rtc[DS1307_MIN];
    hour   = rtc[DS1307_HR];
  }

  // check to avoid glitches;
  if (rtc[DS1307_YR] <= 2050 && rtc[DS1307_MTH] <= 12  && rtc[DS1307_DATE] <= 31)
  {
    day    = rtc[DS1307_DATE];
    month  = rtc[DS1307_MTH];
    year   = rtc[DS1307_YR];
  }
}

void setTime(int hh, int mm, int ss)
{
  getTimeFromRTC();

  // NOTE: when setting, year is 2 digits; when reading, year is 4 digits;
  RTC_DS1307.stop();
  RTC_DS1307.set(DS1307_SEC,  ss);
  RTC_DS1307.set(DS1307_MIN,  mm);
  RTC_DS1307.set(DS1307_HR,   hh);
  RTC_DS1307.set(DS1307_DOW,  1);
  RTC_DS1307.set(DS1307_DATE, day);
  RTC_DS1307.set(DS1307_MTH,  month);
  RTC_DS1307.set(DS1307_YR, year > 2000? year-2000 : year);
  RTC_DS1307.start();
}

void setDate(int newyear, int newmonth, int newday)
{
  getTimeFromRTC();

  // NOTE: when setting, year is 2 digits; when reading, year is 4 digits;
  RTC_DS1307.stop();
  RTC_DS1307.set(DS1307_SEC,  second);
  RTC_DS1307.set(DS1307_MIN,  minute);
  RTC_DS1307.set(DS1307_HR,   hour);
  RTC_DS1307.set(DS1307_DATE, newday);
  RTC_DS1307.set(DS1307_MTH,  newmonth);
  RTC_DS1307.set(DS1307_YR,   newyear);
  RTC_DS1307.set(DS1307_DOW,  1);
  RTC_DS1307.start();
}

void checkButtons()
{
  // increment hours and minutes;
  if (LOW == digitalRead(PIN_BTN_SETHOUR))
  {
    hour++;
    if (hour>23) hour = 0;
    setTime(hour, minute, 0);
    delay(200);
  }
  if (LOW == digitalRead(PIN_BTN_SETMIN))
  {
    minute++;
    if (minute > 59) minute = 0;
    setTime(hour, minute, 0);
    delay(200);
  }
}

2. WiFiChron1284 edition, featuring ATmega1284 SMD
This should be the "ultimate" upgrade for the WiFiChron board. The ATmega1284 processor will provide extra room for the ESP8266 WiFi code (debugging, parsing RSS feeds, data buffering etc).
The PCB design of the new board is shown below. (The boards are ordered and being manufactured).



3. Adapter for dual HDSP display
This adapter, suggested by Ray S, is the new addition to the collection of adapters developed for HDSP clock or WiFiChron.
Combined with the above mentioned WiFiChron1284, it would make a miniature Wise Clock 4 (without the SD card though). The two HDSP-2534 displays share all signals except for the CE (chip enable). The second display uses pin 10 for CE. Writing to each display is done by enabling the right CE line. This allows independent control of each display (dimming, text scrolling etc.).

Photos of the prototype are shown below.






Wednesday, July 8, 2015

LED driver chips

After looking at the many options for driving LED displays (5x7/8x8 matrix, 7/14/16/25 segment, common anode/cathode, single/bi-color/RGB), I put together this list of commonly used LED driver chips, to have a better picture of possible combinations, and use it as reference for future projects.


The bottom 5 rows are not actually LED drivers, just substitutes (require current limiting resistors).

Some of the driver chips (e.g. "8x8" in the "channels" column) provide internal multiplexing, being designed specifically for driving array of LEDs. The others, where "channels" is just one number, would require extra circuitry (e.g. transistors) and logic (micro controller code) for multiplexing.

The "CA" column indicates "common anode", "CC" stands for common cathode.

There seem to be more options for driving common anode LED displays, probably because sinking current (by the chips' LED outputs) allows for higher currents and also for using a separate power source (usually higher voltage) for the LEDs.


Sunday, November 30, 2014

It happened again

Once again, Sure Electronics modified their 32x16 3mm LED display, and this time not only cosmetically.
The two 16-pin shrouded male connectors have been replaced with 10-pin connectors. And the worst thing is that the display now requires 12V for power! Maybe these new displays are intended for use in vehicles powered by 12V batteries. Or maybe designers thought a 12V power source is easier to access than a 5V one. In any case, the display has an on-board DC-DC switching regulator (with XL4013) to make the required 5V.

For someone who needs to replace the older model with the new one, the immediate consequences are:
  • the connector between the driver board (e.g. Wise Clock 4) and the display won't work; connections must be re-wired, probably using an adapter cable;
  • either supply 12V to the board through the connector, or hack the display by soldering the 5V wire directly to the board (see the photos);
  • the holes won't align anymore.

The good news is that the display is electrically compatible with the old one. With the correct re-wiring, the display should work without any software changes.

The following photo shows the testing of the display with the Wise Clock 4 board (and it works just fine).


The display has a series of rail bars that can be used for soldering the 5V power wire, as shown below.


A new design based on this display should (or must) use a 12V power supply. Powering from the USB is not an option any more. This would require a re-design of the Wise Clock 4 board as well (USB connector would be useless now; the FTDI cable won't be able to power the display).

Saturday, November 29, 2014

From the mailbox (with software updates)

New software for the Bubble clock from MikeM:
I have the bubble LED shield working with the DS1337 RTC & LiPo shield.  I have it alternating the display with the battery voltage every 2 seconds right now.  I don't have a voltmeter handy, so I haven't verified what is displayed with actual voltage.  It started fully charged at 4.2v and has now dropped to 4.1v.  It should start blinking at 3.45v, and go to sleep at 3.3v.
I started with your original bubble sketch from the blog posting, but then had to remap all the display pins from the schematic.  The current version of the SevenSeg library doesn't match your code, so I had to make some adjustments.
I also changed the SevenSeg library code to even out the brightness.  It looped through all the segments and turned on each appropriate digit, then delayed and turned everything off.
I changed it to loop through all the digits, turning on each appropriate segment.  Once all the appropriate segments are lit, it turns on the current digit, delays, then turns everything off, then moves to the next digit.  With the previous method some segments were bright and some dim, depending on what was displayed on the other digits.
I also changed the SevenSeg library to not blank leading digits.  It now displays 01.36 for 1:36 AM.  I left it as a 24-hour clock.  I can only display a decimal point, not a colon.
Thanks again Mike!

From ScottH, another version (HDSP.ino only; the rest of the files are unchanged) of the HDSP clock sketch adds scrolling of the time and date and improved setting. Thanks Scott!

From DaveC [on the HDSP clock]:
Here are the pictures.  Hope you find it interesting, unique at least.   There is a slide switch in the back with selections Solar charge, USB charge, USB run (the default mode of the kit), and battery run where you press that button on the front to turn on and display the time.   I used a solar/USB  charge board from Adafruit as I am no EE to figure out how to charge a battery from solar and USB with all of the correct regulated voltages etc.  The case is made from corian and in the top view those speckles are a kind of metallic flake in the corian, the center band is pure black. 




From EricL [on the HDSP clock]:
We got the package last week and my 13 yr-old grandson and I soldered it together and powered it up. Works perfectly!! Then I got your Arduino code for it and programmed it with a flashing ':' between hours and minutes and between minutes and seconds. Then I set the date in the RTC and changed the code again. Now it shows the date for 2 seconds every minute. Nice! Thanks for a great project!

From GregoryK [on the HDSP clock]:
Your kit is fantastic. Simple but well thought out. Thanks for bringing it to the market!
I would like to use it in one of my classes at Stanford as an "intro to soldering" and "intro to Arduino hacking" (they already will be familiar with the Uno) project.

From IvanS [on Wise Clock 4]:
Thank you Florin for the very thoughtful and entertaining  gift. Anything based on electronics is always interesting to me. We have been reading the famous quotes all day. It was a pleasure to meet you [...]

Saturday, August 30, 2014

Back in "business"

Just returned from my vacation in Paris. Hotel de Crillon was closed for renovations, Ritz had limited availability also due to renovation, so I had to settle for The Peninsula ;)


Here are a few impressions and observations, while still fresh.
  • taxis only take cash; ride from the airport to Paris center is about 60 euro and takes about 50 minutes;
  • the lowest cost Starbucks coffee is twice as expensive as here, at about $4.5 (3 euro), but still a lot cheaper than the "cafe creme" at Les Deux Magots or Cafe de Flore;
  • cheques are still used for grocery shopping (!);
  • the fixed air conditioning units (installed outside the windows) are probably not allowed, since they would really spoil the beauty of the buildings; posters are also forbidden, though I saw some "pixel art" placed high (that is, hard to remove) on some buildings;


  • one can actually live on and retire from a job as waiter or hotel concierge;
  • tipping in restaurants or for services is not a habit;
  • selling padlocks around famous places is big business;
  • Lacoste has a "lab" which also makes beautiful bicycles (this may be of interest to Justin :)
  • great Star Wars animatronics in DisneyLand Paris;




  • charging stations for electric cars;
  • and finally, a (probably expensive) clock :)