Tuesday, December 28, 2010

Morse Code Chart in a geometric Sense

I like the idea of this chart because it make some sense!
You can her the whole alphabet of morse as midi file (download it first).


Source: http://9w2pju.hamradio.my/2009/09/morse-code-chart.html

LEARN MORSE CODE in one minute !
This is a code listening tool. Print it on your printer.
Place your pencil where it says START and listen to morse code.
Move down and to the right every time you hear a DIT (a dot).
Move down and to the left every time you hear a DAH (a dash).
Here's an example: You hear DAH DIT DIT which is a dash then dot then dot.
You start at START and hear a DAH then move down and left to the T and then you hear a DIT so you move down and RIGHT to the N and then you hear another DIT so you move DOWN and RIGHT again and land on the D
You then write down the letter D on your code copy paper and jump back to START waiting for your next letter.
The key to learning the code is hearing it and comprehending it while you hear it.
The only way to get there is to practice 10 minutes a day.
Listen to code tapes or computer practice code while tracing out this chart and you will find yourself writing down the letters in no time at all without the aid of the chart.
The chart brings repetition together with recognition, which you don't get from any other type of code practice aid.
HEAR slow morse code This code speed is slow enough to follow the chart above.

LEARN the DITs and DAHs with these MP3 files:

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z 1 2 3 4 5 6 7 8 9 0

And the character to emphasize that there she was, she was walking down the street, is :

Goto DOWNLOADS page for hours of MP3 code practice
email KB3BYT



source: http://www.learnmorsecode.com/

This introduction is my best to the subject:

How to learn morse code. And enjoy it.
Morse code is not a chore. Its a challenge.
Its a challenge of your ability to learn a new language.
And it is truly a language.
There are millions of people who successfully learn a foreign language
so you can be certain that its not so farfetched to think that you too may learn a new language.
The secret to learning a language is to jump into the pool, over your head, totally emerse yourself in your new language.
If you want to speak Chinese then the best way to learn Chinese is to go to China and only hear Chinese.
We all can't do that.
But we can come real close with today's recording technologies with cassette tapes and DVD and CD and MP3 recordings.
Morse code is the same. Listen to it. All the time. It doesn't matter if its just slow  or just fast.
It doesn't matter if you do not understand  a single  word at first.
There are a dozen methods to practice and get your brain to retain what the letters are.
Practice reinforces and recognition will come with practice.
Then... one day ... you start hearing entire words and sentences that make sense..at speeds that
you never dreamed you would understand.
Some peple say that you should never use a chart or any visual aid to learn morse code.
All people are created a bit different and what works for some people , does not always work for everyone else.
So don't try just one method to learn morse code. Try a few and decide what works best for you.
This chart at  http://www.learnmorsecode.com is just one of many methods to learn morse code.
This particular method will work for all ages to immediately put together the noise of morse code with the meaning
of the noise. It does not matter if it is a slow process. All that matters is that your brain gets a chance to connect the dots and make some meaning out of it all.
Many people give up trying to learn morse code beacuse they do not ever get the noise to stick in their brain and recognise what letter they just heard.
This method will sew together that recognition if you practice this method for 10 minutes every day with the
SLOW code A-Z file.
After you no longer need the chart...then...and only then....move on to the faster code practice download files.
There are computer programs that can make morse code to teach you.
I like  the software at  http://www.g4fon.net/
I highly recommend you use that software to learn the letters and also to make your own practice audio files.
If you can not make a computer do recordings and carry around MP3 files
then use cassette tapes. They are cheap to make and WALLMART sells casette players for $5.00 now.
The computer programs that generate practice morse code are great
and FREE so have fun with it.
One method to learn morse code is called CODE QUICK.
CODE QUICK has you listen to a letter and associate small sentences with the sounds
of the morse code. An example of this method is to hear the letter K in morse code
which is made up of the sounds DAH DIT DAH.
You hear the DAH DIT DAH and it actually sounds like KANG ga ROOOOO.
So your brain hears the DAH DIT DAH and injects KANGAROO into your minds eye
and you say AH HAA!!!! KANGAROO begins with a K so what I just heard was a K !!!!!
You write down the K and along comes the next letter.
There are SOUND ALIKES for every letter of the alphabet and numbers too.
You are encouraged to make up your own sound alikes for the
letters if you have trouble using the CODE QUICK sound alikes.
CODE QUICK taught me morse code at a time where no other method worked for me.
I did not learn about the LEARNMORSECODE.COM chart until years after I used CODE QUICK.
You can BUY code quick at http://www.cq2k.com for around $30.
The methods used at code quick are very straight forward and actually have been around
for many many years before the code quick author published the first code quick
casette tapes and work book course.
I have an uncle that was a code listener during the Vietnam war and one day he visited
me during a morse code contest and very fast morse code was playing on my radio and it
was was too fast for me to understand and my uncle sat down next to me and asked me what I
was doing and I told him I was trying to understand the hailing station but I was too new at
it to understand.
My uncle told me what the station was saying and then told me about his code listening days
so I asked him to respond and he told me that he never sent a single dit in all those years.
All they did was spy on the enemy.
He understood the fastest of the code so I asked my uncle to explain to me the method that
the army used to teach him the code in 1965 and he told me that the army made them memorise little
phrases like a baby crying wants his mother to give him a drink of water and
that sounds like MaWAWA and is the letter W ...DIT DAH DAH.
That just blew my mind because that was precisely what CODE QUICK used to remember W also.
This man was a high speed spy listener that got his first morse code training with this learning method.
So this method truly works but you will have your sticks in the mud old farts telling you
that CODE QUICK sound alikes will only slow you down from learning truly high speed morse code at 20 words per minute.
Well to hell with sticks in the mud.
If you learn morse code at 5 words per minute using sound alikes and have fun with listening
to any morse code then moving up to high speed code will be another challenge and practice
is what makes perfect.
You will find that if you know 5 words per minute slow speed morse code and you listen to
ramp recordings where the letters are played slow at first and then ramp up to real fast
code of the same letters, the ramped up speed will stick to your brain quite
well because you already knew what the slow letters sounded like and you will enjoy the
comprehension instead of being all wrapped up in being lost in fast practice code.

So thats my 2 cents on learning morse code.
Have fun.
from Rob KB3BYT
source: http://www.learnmorsecode.com/

Sunday, December 19, 2010

Airband_VHF_1T_Regen_High gain audio amp required

R1, R3    =    47K 1/4W Resistor   
R2    =    10K 1/4W Resistor   
R4    =    4.7K 1/4W Resistor   
R5    =    5K Linear Taper Pot   
R6    =    2.2K 1/4W Resistor
C1, C2  =       0.001uF Ceramic Disc Capacitor
C3, C6    =    0.001uF Ceramic Disc Capacitor
C4    =    2.2pF Ceramic Disc Capacitor   
C5    =    1pF Ceramic Disc Capacitor   
C7    =    15uF 15V Electrolytic Capacitor   
C8    =    18pF Variable Capacitor   
D1    =    1N82 Diode   
Q1    =    2N918 NPN Transistor   
L1    =    See Notes   
L2    =    1.8uH Inductor   
ANT1    =    Approx. 18 Inch Wire Antenna   
MISC    =    PC Board, Wire, Knob For C8  

The communications between commercial aircraft and the ground can be interesting, amusing and sometimes even disturbing. However radios that receive the approximately 220MHz to 400MHz band commonly used for aircraft (both military and commercial) are not easily found. And scanners can be complicated, large and expensive. With an easy to build circuit such as this one, everyone can enjoy listening in on these conversations. 

# The circuit originally appeared in the Think Tank column of the Sept. 1995 issue of Popular Electronics.

# L1 is made by winding 2 turns of 22 AWG magnet wire on a 5/32 drill bit. This inductor can be modified to shift the frequency range of the circuit.

# The antenna can also be placed at the anode of D1 if overload is a problem with it connected to the emitter of Q1

# R5 adjusts regen and thus sensitivity.

Source: http://www.project-world.co.cc/links/schematics/radios/ABS.html

Saturday, December 18, 2010






MW_1T_Reflexive_High gain audio amp. required


Meter_Bipolar Beta Meter


Meter_Audio Frec. Inductance Capacitance Meter

Thursday, September 23, 2010

Equivalents of Russian Transistors

1. Bipolar transistors

Russian part

Short description

Western analog

KT3102A general use n-p-n silicon transistor BCY43, BC107A, BC170, BC207A, 2N4123, MPS3709


npn silicon transistors with high h21e (>600)

2N5210, for example
KT312A-B general use n-p-n silicon transistor Almost the same as KT315, excluding case type.
KT608A HF middle-power silicon n-p-n transistor BSX21, 2SC796
KT606A-B middle-power silicon n-p-n transistor for use on HF and VHF applications Couldn't find, sorry
KT326 Common general-use p-n-p silicon device. I guess, any appropriate western transistor will be able to replace it. I wonder, why i can't find it in my databases...
KT602B rather old n-p-n silicon transistor, specially designed for working in final stages of wideband amplifiers. BSY71
GT308 Very old general-use p-n-p germanium transistor. Can't find, sorry.
GT311 Old, but still good germanium n-p-n device for working with frequencies up to 800 MHz. Can't find, sorry.
KT315 general use n-p-n silicon transistor, an old design BC146,
GT402 low-frequency germanium p-n-p transistor, old design Do not know*
GT404 complementary pair for GT402 Do not know*
MP25A-B Very old p-n-p transistor for 'draft' purposes ACY19, ACY23, 2N190-191
KT503A general use n-p-n silicon transistor (for rather low frequencies) 2SD762, for example
P214A Very old p-n-p high-power transistor for low frequencies AD142, for example
KT368A-B Very good high-frequency n-p-n transistor with low noise factor BFS17 , 2SC252
KT812A high-power transistor for low frequencies (n-p-n) KU601, KU602
KT815 Middle-power n-p-n silicon transistor for use in low-frequency circuits BD165
KT814 Complementary pair (p-n-p) for KT815 BD170
KT818G High-power p-n-p transistor, widely used in power supplies and output stages of AF amplifiers. AD142
KT819G The same as KT 818G, but with n-p-n structure BDY20, BDY23
KT940A high-voltage transistor for final stages of video-amplifiers in TV BF338

* - I suppose, any general use germanium transistor will work instead.

2. Field-effect transistors

Russian part

Short description

Western analog

KP303A n-channel JFET with rather low amplification haven't found*
KP307B n-channel JFET, general use 2N3819
KP302A the same as above haven't found*
KP303E the same as above MPF102
KP350A two-gate n-channel MOSFET transistor 2SK39
* Though I haven't found a direct equivalent for this device in my databases, it seems to me,that they are replaceable to 2N3819 and other general-use JFETs (may be, with a slight correction of DC conditions)

3. Analog and digital integrated circuits

Russian part

Short description

Western analog
K544UD1 General-use operational amplifier with high input impedance CA740
K155LA3 four TTL 2&-not elements SN7400
K155LA12 the same as LA3, but with more powerful outputs SN7437
K155IE2 Asynchronous TTL counter.. Has two counters inside - one counts up to 2, the second - up to 5. They may be used separately or connected in series forming a decade. SN7490
K155TM2 Two dynamical TTL triggers of 'D'-type. Also has external 'set' and 'reset' inputs. SN7474
K155TM7 Four TTL triggers of 'D'-type. Ideal for using as a 4-bit storage device SN7475
K155ID6 A simple 4 -> 10 decoder SN7442
K514ID2 4 -> 7 decoder with blanking input for a 7-segment indicator (LED, for example) MSD101
K500LP116 Three differential ECL receivers/amplifiers MC10116
K500TM131 Two ECL D-triggers MC10131

Valentin Gvozdev, Moscow

Source: http://matthieu.benoit.free.fr/cross/russian_equiv.htm

Wednesday, September 22, 2010

MW_TRF Good Radio_1T_1IC_2Diodes

Here's a very simple AM Radio circuit I've designed couple of years ago. Don't know whether anybody listen to AM stations anymore. But I still use it(maybe I wanted to listen to my own built radio lol..). The radio section is wired using a single transistor(BF494) and it was so amazing that an audible sound is recovered at the output which is faint though. It doesn't use any external antenna and the sensitivity/selectivity of the receiver is pretty good. However I used an amplifier(TA 7368P Toshiba, Low voltage) which drives an 8ohm/1W 4" speaker inside a box rocks the entire room with a high fidelity audio that is unbelievable and outperforms Superheterodyne ones in this regard . It is a reflex receiver.

The audio recovered at inductor L is rather strong comparing to ZN414 and free from oscillations.(I've never succeeded in building ZN414 which always give me annoying motorboating and chirping crappy I say!)

Using a flat ferrite bar antenna allows local reception for a pocket radio and a big rod antenna captures stations beyond 200miles! So it doesn't require an external wire antenna, adding it only helps in electrical noise catch.

Only critical part in the circuit is inductor L, its optimum value gives excellent results. Make rf parts close to the transistor. I made it on a 1.5" ultra small pcb. 2 x AA battery lasts very long.

Another important thing is that the radio is absolutely silent in between the stations - means no noise at all if no any electrical interferance which is a plus point over Superheterodyne receivers. It was so amazing to tune it during power failure period. So I'll call it a true radio.

Source: http://www.electro-tech-online.com/electronic-projects/94129-simple-am-radio-receiver.html

Suggestion: Replace the upper diode by a Germanium one for more sensitivity.