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Showing posts from February, 2012

Sometimes its fun to finish last...

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In the US we pride ourselves on our ability to compete and we admire those that achieve and finish in first place.  There are times when it is great fun to finish last.  Last night we received a SKED request for a ham who needed only one more contact to finish the ARRL Triple Play Award (TPA).  He had acquired 149 contacts (50 digital + 50 phone + 49 CW) and needed only 1 final CW contact with a New Jersey station to finish the award requirements.



We were really excited to have an opportunity to help complete the award.  Triple Play is a wonderful and challenging amateur radio award.  We completed TPA some time ago earning #464.  The final few contacts can be quite difficult to secure.  So the prospecting of being the final contact made this SKED extra important.  We were determined to do whatever it took to make the contact.

We arranged a time and met on K3UK's SKED site and agreed to move to 40m.  A few station adjustments were required since our station had been off the air for…

Fathers and Sons

When you teach your son, you teach your son's son.  -- The Talmud

KN-Q7A Single Band SSB Transceiver Kit - Step 6: Mixer and VXO Local Oscillator

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This is the 9th article in our series on building the KN-Q7A Single Band 40m SSB Transceiver Kit. In our prior article, we completed the IF Crystal Filter.
In this article we proceed with building Step 6: Mixer and VXO Local Oscillator.  VXO is the abreviation of Variable crystal oscillator. We followed the instructions and installed the parts without incident.  We installed the 15.550 Mhz VXO crystal.  We also have a 15.418 VXO crystal which we intend to save and experiment with another day. We touched pin 1 of the NE602A with an antenna cable tip as suggested by the instructions and detected band noises.

Lessons Learned Our good old PanaVise 301 holds the circuit board securely making component placement and soldering very easy.The instructions indicate touching pin 1 of the integrated circuit.  Beginners may find that locating pin 1 is a little confusing without a graphic. We were unable to detect the VXO frequency change on our general coverage receiver on 7.280 ~ 7.300 Mhz.  We were…

Heinrich Rudolf Hertz Birthday

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Heinrich Rudolf Hertz was born this day February 22, 1857.  Hertz was a physicist who clarified and expanded the electromagnetic theory of light that had been put forth by Maxwell.  He was the first to conclusively prove the existence of electromagnetic waves by engineering instruments to transmit and receive radio pulses using experimental procedures that ruled out all other known wireless phenomena.

What is engineering?

Q) What is engineering?

A) There are many definitions of engineering:

- Engineering is the purposeful use of science.  - Steve Centuria, MIT

- Engineering is the practical application of science and math to solve problems.

- Engineering is the discipline, art, skill and profession of acquiring and applying scientific, mathematical, economic, social, and practical knowledge, in order to design and build structures, machines, devices, systems, materials and processes.

- Engineering is the application of scientific and mathematical principles to practical ends such as
the design, manufacture, and operation of efficient and economical structures, machines, processes, and systems.

- Eningeering is the creative application of scientific principles to design or develop structures, machines, apparatus, or manufacturing processes, or works utilizing them singly or in combination; or to construct or operate the same with full cognizance of their design; or to forecast their behavior under speci…

Famous Quotation: Learning

Learning is not compulsory... neither is survival. -- W. Edwards Deming

KN-Q7A Single Band SSB Transceiver Kit - Step 5: IF Crystal Filter

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This is the 8th article in our series on building the KN-Q7A Single Band 40m SSB Transceiver Kit. In our prior article, we completed the receive intermediate-frequency (IF) amplifier.   The IF amplifier section amplifies signals after they have been converted to the fixed intermediate-frequency value by the frequency converter.

In this article we proceed with building Step 5: IF Crystal Filter.  This section provide post IF amplifier filtering of the received signal.  The filter circuit consists of a network of 6 crystals and 7 capacitors along with 2 relays.

We followed the instructions and installed the parts without incident.


Lessons Learned
Having your parts sorted in a muffin tray or something similar really makes it easy to locate the correct parts quickly.Orient the crystals and capacitors the same way for a more pleasing appearance. In the next installment the fun continues as we proceed with building Step 6: Mixer and VXO Local Oscillator.

Other related articles on NJ2X.COM:
KN-…

FCC Blocking Telemarketers and Robocalls

The Federal Communications Commission (FCC) recently announced that they will be taking action against annoying telemarketer "robocalls" or computer driven calls to residential phones.

We recently had the pleasure of experiencing what life is like when off of on the do-not-call registry.  It was a real eye-opener and resulted in a barrage of telemarketer calls at all hours including robocalls.  The robocalls would often repeatedly call again and again throughout the day.

Under the new rules, telemarketers must first obtain written consent from consumers before calling or sending text messages even if they are not on the do-not-call registry.  All robocalls will also be required to include an automated opt-out option to allow consumers to notify telemarketers that they no longer want to receive calls.

What we find amazing is that telemarketers invest so much effort in telemarketing when it is so universally hated.  What other business or charity succeeds by annoying its custo…

Russian WW PSK Contest

The Russian WW PSK Contest from 21.00 UTC on Friday 17th February till 21:00 UTC on Saturday 18th February, 2012.

Types of modulation: BPSK31, 63, 125. The output power should not exceed 10 watts on 160 meters and 100 watts on other bands. Only one transmitted signal is permitted at any time. Bands: 160 m, 80 m, 40 m, 20 m, 15 m, 10 m.

Categories: SOAB, SOSB, MOAB. The Russian participants should send RST(Q) plus 2-letter abbreviation of Russian Area (oblast) Code (example for Moscow region – 599 MA). Foreign participants should send RST(Q) plus QSO number, starting 001 (example - 599 001). The numeration on bands is current. General call - "CQ RUTEST". The repeated contacts are permitted on different bands and different modes providing that a contact will be made not earlier than in 3 minutes.
The contest awards will receive all beginners of PSK-contesting. The plaque will be raffled for the thousandth participant of the contest... We invite all radio amateurs all over the w…

New Jersey QSO Party - July 28/29, 2012

Mark your operating calendar!  The New Jersey QSO Party will be back on the air July 28 and 29, 2012.  This is great news for New Jersey hams since it a great event.  2011 sadly marked the first time in memory that there wasn't a New Jersey QSO Party event. 

A big thank you to the Burlington County Radio Club for sponsoring the NJ QSO Party and bringing the event back.

The objectives for the New Jersey QSO Party are:
Contact as many NJ amateurs in as many NJ counties as possible. NJ stations contact as many Amateurs in the US, Canada and the world as possible. For more information be sure to consult with the New Jersey QSO Party Rules.  Please spread the word about this wonderful event.

Windows 7 Is A Great Teacher

Here we go again....

We recently spent the better part of a weekend struggling with Windows 7 / PC / hard disk issues.  There are few things we enjoy less than having to invest our precious time digging into esoterica to remedy PC issues.  However, this is a well established pattern of modern life.

Millions of computer owners go through similar experiences every few years if lucky or every few months if less lucky.  Each time we get to learn (or re-learn) about things like:
sfc /scannowscandiskdefragmentingrestore pointsbackupssystem file repairtools for analyzing, cleaning, and repairing issuessetup diagnosticswarrantiescalling the manufacture for support... It is amazing it all works (most of the time).  What is equally amazing is the tremendous amount of trivia, advice, and often misleading information available on the Internet regarding Windows 7 OS and correcting the miriad of problems that can occur.
At this point we have worked through the layers of issues down to the root cause…

Famous Quotation: How to do it

Whenever you are asked if you can do a job, tell 'em, 'Certainly I can!' Then get busy and find out how to do it. -- Theodore Roosevelt

KN-Q7A Single Band SSB Transceiver Kit - Step 4: RX IF Amplifier

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This is the 7th article in our series on building the KN-Q7A Single Band 40m SSB Transceiver Kit. In our prior article, we completed the Detector / Double Sided Band Modulator. In this article we proceed with building step 4: RX IF Amplifier.

We followed the instructions and installed the parts without incident. 

The function test involved confirming that audio increases or decreases relative to changing the potentiometer.  We were very pleased that the test passed the first time.

Lessons Learned
Confirm the potentiometer is the correct one before soldering.  The two potentiometers in the kit look similar and are different.The MC1350 integrated circuit does not have a notch.  Instead it has a dot identifying pin 1.  Orient the chip on the board so that the dot is closest to the notch demark on the board.  Would be helpful to inexperienced builders to have this explained in the instructions. In the next installment the fun continues as we proceed with building Step 5: IF Crystal Filter.

What is the schematic symbol for a ferrite bead?

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This is a ferrite bead.


So what is the schematic symbol for a ferrite bead?

According to the IEEE 315 standard for Graphic Symbols for Electrical and Electronics Diagrams, the ferrite bead schematic symbol is:



Additionally, there are several other ways commonly used to denote a ferrite bead on a schematic:



Good DX and 73,

NJ2X



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Special Event: Thomas Edison's Birthday

The West Essex Amateur Radio Club (W2EF) will be commemorating Thomas Edison's Birthday on Feb 11, 2012 from Caldwell, New Jersey.
Feb. 11, 201215:00Z - 21:00Z146.5521.37714.2777.177Certificatehttp://www.wearc.org

Book Review: The Road Home by Andrew Baze

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The Road Home by Andrew Baze
200 pages, Max Publications, 2011

The Road Home is story about surviving a disaster when all else fails (e.g. telephone / mobile phones, police, fire, roads, water supply, gasoline, power, stores, ...).  It is an engaging page turner suitable for pre-teen, young adults, and adults alike.  The story centers around a family's fight for survival during a major natural disaster.  Woven into the story are examples of how emergency preparation and self-sufficiency pay off when the unexpected happens. 

The story also illustrates the importance of a strong family when dealing with adversity.  Amateur radio plays an important role in helping through the disaster by being a life saving communications tool.  The story also reminds us of what can happen to those that do not prepare or have a survival mindset.

The action packed story will likely connect with young adults and make an impression about preparedness.  The characters are normal people and easy to relat…

Ab Absurdo - HOA Friendly Low Profile Antennas

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© Michael W. Maher and NJ2X.COM, 2012. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Michael W. Maher and NJ2X.COM with appropriate and specific direction to the original content.

KN-Q7A Single Band SSB Transceiver Kit - Step 3: Detector / Double Sided Band Modulator

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This is the 6th article in our series on building the KN-Q7A Single Band 40m SSB Transceiver Kit.   In our prior article, we completed Step 2: the audio amplifier.  In this article we proceed with building step 3: Detector / Double Sided Band Modulator.

We followed the instructions and installed the parts.  Again, we would prefer a checklist of parts instead of working from the picture to figure out which parts to install.

We inadvertently installed a 103 capacitor in a location intended for a 104 capacitor.  We discovered this when we found we were short 1 103 capacitor.  We corrected this easily by de-soldering with the aid of a solder sucker and then re-soldering the part in the correct position on the circuit board.

To test the circuit we used our TH-F6A HT which as a wide-band scanner covering HF to check for the presence of BFO leakage on the IF crystal's frequency.  The instructions were written for a test assuming an IF crystal frequency of 8.465 Mhz.  Our kit used a 8.192…

Famous Quotation: Learn

The wisest mind has something yet to learn. -- George Santayana

KN-Q7A Single Band SSB Transceiver Kit - Step 2: Audio Amplifier

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This is the 5th article in our series on building the KN-Q7A Single Band 40m SSB Transceiver Kit. In our prior article, we fabricated an Anderson Powerpole to 2.1mm Connector Pigtail to supply power to our kit through the jack. In this article we proceed with building step 2: audio amplifier.

We followed the step-by-step instructions for installing each component.  However, when we got to the capacitors and resistors, the instructions simply said, "solder the remaining capacitors and resistors; when finished, it will look like the photo".  Each component is marked on the circuit board which helped.  Using the circuit board and photo, we were able to figure out which parts to solder and the location.  We would have preferred a little more guidance.  In our opinion, it would have been helpful to provide a checklist identifying each part to be installed.  We did like having the picture as a guide though a larger photo would be helpful.
The final activity for completing the audi…

EPC WW DX Contest 2012 - Feb. 4, 2012

EPC WW DX Contest 2012 will be held from 12:00 UTC on Febraury 4, 2012 to 12:00 UTC until February 5, 2012 on the BPSK63 mode.
If you have any questions contact the Contest Secretary at http://www.epcwwdx.srars.org/index.php/contact.html

Special Event: Buddy Holly Memorial, 53rd

W5B will be commemorating the 53rd Anniversary of the death of Buddy Holly from Lubbock, TX.
Feb. 3, 2012 through Feb. 5, 201215:00Z - 04:00Z18.15014.2607.2603.860http://ww.amcrc.com/w5b