'Get On The Air'

'Improve Your Signal' Presentation

Our first SARC General Meeting of 2020 was Wednesday, January 8th. 

One of our best attended presentations ever

As a result of feedback from our Basic courses, we planned a presentation and panel discussion around the basics of getting started in Amateur Radio. This was intended not only for new Hams but also those looking to improve their station capabilities.

We covered primarily VHF/UHF gear, antennas, power and accessories. Based on the interest in this session we will host a similar topic focusing of HF later in our meeting schedule.

We asked our SARC members to bring along any good used gear for sale and a few items showed up.

By request, here is the slide deck from the presentation:
https://drive.google.com/file/d/1TkZWzDsznMV1hbcq69Jwtn9AxSp3MCXW/view?usp=sharing

We hope to have an accompanying guide available here shortly.

~ John VE7TI

Back To Basics: Overmodulation

Overmodulation Leads To Interference!

Question B-001-019-003 (A) - From the Canadian Basic Question Bank:

An amateur station using radiotelephony must install a device for indicating or preventing:

a. overmodulation 
b. resonance 
c. antenna power
d. plate voltage

The  key word here is must. All four of the above can be measured in a transmitting station but not all are required to be indicated or prevented. Only one is harmful to the extent that it can seriously affect enjoyment of the airwaves and cause interference to other Amateurs.

Overmodulation is the condition that prevails in telecommunication when the level of the modulating signal [the intelligible portion holding information— such as spoken audio from a mic] exceeds the value necessary to produce 100% modulation of the carrier. A carrier signal is one with a steady waveform, constant height (amplitude) and frequency shown in the diagram as the envelope. Modulation is superimposed on the carrier at the transmitter and recovered at the receiver.

In layman's terms, the signal is going "off the scale". Overmodulation results in spurious emissions by the modulated carrier, and distortion of the recovered modulating signal. This means that the envelope of the output waveform is distorted. The usual way of ensuring you are not over-modulating is to use the ALC on your HF radio, which will tell you if the audio level is too high.  It is also good practice to monitor your own audio while transmitting to ensure you are not too close to the mic or speaking too loudly, as the presence of distortion will be a sure sign that your audio is driving the transmitter too hard.

In the diagrams above, A indicates an Amplitude Modulated (AM) signal that is modulated to a low percentage. When modulation is increased to 100%, as in B, we are on the threshold of overmodulation. When increased above 100% as in C, the signal is said to be overmodulated resulting in distortion and spurious emissions.

See a demonstration here on YouTube.

There are several questions on overmodulation in the question bank and one is always on the Basic exam.

Resonance is a desirable state when tuning to a specific frequency but does not have to be measured.  Antenna power and plate voltage may be measured but that is also not mandatory.

The correct answer to this question therefore is ‘A’ Overmodulation.

More information on overmodulation? 

https://books.google.com/books

~ John VE7TI

New Year's Resolutions: 2020 Edition

Happy New Year!

The New Year has arrived and Hams, like so many others, may have a few resolutions to consider. I think we all recognize that the hobby is going through change. While the number of licensed Amateurs in North America continues to increase, likely due in large part to the ease with which a license exam can be passed, the number of ‘active’ hams seems to be diminishing. One only has to monitor a repeater or tune in to a weekly net to realize that participation has dwindled. With this in mind, I offer a list of amateur radio new year’s resolutions and encourage you to try to adopt some or all with your own goals for 2020.

On the west coast we hear about the impending ‘300-year’ earthquake frequently and have regular drills to prepare, including checking into an emergency net. That earthquake could happen tomorrow or at some point past our lifetime—despite some believable scientific data, no one knows for sure. But there are more common calamities that could happen sooner, and have over the past few years. A major snow or wind storm… an extended power outage.

"Five minutes before the party is not the time to learn to dance"

It is a good idea to make preparations now without the stress of a fast approaching deadline. If you are thinking of replacing or building an  antenna for use in an emergency, now is the time to build it and test it out at a leisurely pace. We have in the past, and will continue to present, home built antenna projects in SARC publications. If you’re not that handy, ask about the antenna workshop we offer to all our Basic course students. We also have a cadre of willing ‘Elmers’ who will help you with advice and assistance to set up that antenna.

Another aspect of Amateur Radio that comes into focus now is contest season. There is a contest every weekend in January, just check the calendar on: https://www.contestcalendar.com/. 

SARC has a contest group with tutors, and we invite your participation. Even if you only have a passing interest in contesting, come and try it at least once. Emergency focused radio operators will find contesting has many of the same challenges, and you will improve your skills, thereby becoming a better communicator.

Have a go at operating away from your usual location. It has been dubbed “Ham Radio Alfresco." There are so many hills, parks and beaches in our area that if you can’t find a place to throw a little wire in a tree and operate with low power off a battery, you aren’t looking hard enough. Your “portable” station can be anything from a  handheld or QRP single band rig to one of the big three’s latest 100 watt wonder radios that do everything from DC to Daylight. Just turn the power down so the battery lasts more than 10 minutes and you too can add another few ‘Qs’ to your logbook.

If you are thinking about trying to upgrade your license, now is the time to start studying. If your storage shed has a ton of old radio stuff in it, get busy and drag it all out into the sunlight and sort it out or throw it out. If you find you have a working radio or accessory that you do not need any more, consider donating it to your local Amateur Radio group. 
Come to a monthly meeting. You will find interesting presentations, lots of information and friendly fellow SARC members.

And lastly, please make an effort to use our repeaters once in a while. It would be very encouraging to hear some conversation outside of net night but, speaking of our net, please check in there too, we meet every Tuesday at 8pm 147.360 MHz (+600 KHz) Tone=110.9, or via Echolink.

73, and Happy New Year!

~ John VE7TI, Editor

The January/February 2020 Communicator

Here is the Latest SARC Communicator

Projects, News, Views and Reviews... 

Happy New Year from all of us here at SARC!

Here is the January/February 2020 SARC Communicator newsletter: 

http://bit.ly/SARC20JanFeb

This edition has 75 pages of projects, news, views, and reviews from the SW corner of Canada. 

• VY0ERC: What is life like at the farthest north Amateur Radio Club in Canada?
• Building a moonbounce (EME) station on VHF
• Make a 6m receiver with Arduino and a handful of parts
• A 3-pin radio IC
• A soldering primer
• Remote rotator control
• AA-600 Antenna analyzer review
• The BC QSO Party 2020
• Tech tips
• No-ham recipe
• and much more!

Past articles and issues are available on our blog at https://ve7sar.blogspot.ca

We always welcome contributions of news, stories and your Amateur Radio experiences. The deadline for the next issue is February 15th.

73,

John VE7TI
Communicator Editor

The SARC CW Course

Morse Code Is Not Dead!

CW – the Original (and arguably, the best) Digital Mode

Invented in 1837, CW which is more commonly known as “Morse Code”, was the very first mode of communication sent over a wire or airwaves.  It is called CW or “continuous wave” because it is an unmodulated radio wave of constant amplitude, though it might more accurately be called “discontinuous wave” since the wave is broken into short and long segments separated by spaces, to represent letters of the alphabet, numbers and punctuation marks.  It is legitimately a digital mode because it exists in only 2 states  –“on” or “off”.

The length of the dot (or “dit” as we prefer to say) and dash (or dah)  and the spacing between them is not arbitrary but has a fixed relationship.  If the relationship is not accurate, the quality of the CW will be recognized as “poor” and in extreme cases may be virtually unreadable.  While most CW heard nowadays is created by software and is therefore perfect, we occasionally hear on the radio less-than-perfect Morse Code, sent by operators still using a mechanical device such as hand key or bug.

Since CW has largely been abandoned by the commercial, military and transportation world, it is now virtually within the sole domain of amateur radio operators, whose passionate adherents will likely stand by it to the bitter end.  So, if you think CW is dying out, then listen on the 20 m band during one of the many CW contests throughout the year.  You will be amazed at the number of CW operators sending Morse Code at rates between a lazy 15 wpm and the a breakneck 50 wpm or more, from every corner of the world.  

If you wish to use radio to communicate by the most reliable and sensitive means, you will not use CW at all, but instead one of the modern “weak signal” digital modes such as FT8, JT65 and a whole slew of others,  which have transformed our ability to accurately copy signals which may be so weak that you cannot actually hear them.  This is a boon to communication as it allows information to be exchanged even when using low power transmitters and poor antennas – unavoidable for condo dwellers.  So these forms of digital certainly have their benefits.  

However, if you wish to enjoy amateur radio in the most traditional, challenging and enjoyable way, you will find CW is the method of choice.   Yes, you can deploy digital decoders to help you read CW on a computer monitor, and many do.  However, even the best digital decoders are inferior to your ears and brain working together.  So if you are serious about using CW, you really must learn to copy it by ear.  

As a beginner, you will likely start with a hand key to send the characters which require a separate wrist movement for each dit and each dah.   In the past, CW operators would typically graduate to a semi-automatic key called a “bug” which sends a series of dits when the paddle is pushed one way, but single dahs when pushed the other way.  That certainly takes some of the work out of sending.  Actually very few CW operators now use a bug although the holdouts can still be heard on the airwaves.  

CW sent by a hand key or bug is usually distinctive of the operator and can often be recognized in the same way that a person’s individual handwriting differs from that of others.   During WW 2 the identity of German and British radio operators could often be recognized by their “fist” i.e. individual way of sending code characters.   

Hand key

  

Semi-mechanical Vibroplex “bug”

Nowadays, 95% of CW operators use a paddle and electronic keyer to send CW.  This combination is a big step up from the hand key and bug because it allows sending virtually perfect CW, which means the dits and dahs are of the correct length and spacing.  The keyer can be a separate unit into which you plug your paddle or, more commonly, it is built into the transceiver.  You push the paddle one way and it makes a string of dits; push it the opposite way and it makes a string of dahs.   It is not difficult to master and the result is uniform and perfectly formed CW.

Kent paddle

Bencher paddle

Electronic keyer with built-in paddle

External Electronic keyer which requires a separate paddle

You may occasionally hear about “iambic keying” which allows the keyer to minimize the keystrokes or hand movements even further.  To visualize how it works, consider the letter “C” which can be sent iambically by merely squeezing the two paddles together. With a single-paddle or non-iambic keyer, the hand motion would require alternating four times for C (dah-dit-dah-dit).  Most CW operators have not mastered this technique and it is not recommended for beginners.

If you’re stuck in a rut and looking for a new and challenging experience, consider learning CW.  Persistence and practice will get you through in the end and you will be ready to join the select group of hams known as “CWers”.  I heartily recommend it.

~John VA7XB

We Wish You Joy!

And perhaps a Ham toy in your stocking

We here at

Surrey Amateur Radio Communications

wish you a joyous holiday season and

a very happy and prosperous New Year!

An old favourite:

'Twas the night before Christmas,  

And all through two-meters,  

Not a signal was keying up  

Any repeaters.

The antennas reached up  

From the tower, quite high,  

To catch the weak signals  

That bounced from the sky.

The children, with Basic,  

Took their HT's to bed,  

And dreamed of the day  

They'd be on HF, instead

.

Mom put on her headphones,  

I plugged in the key,  

And we tuned 40 meters  

For that rare ZK3.

When the meter was pegged  

By a signal with power.  

It smoked a small diode,  

And, I swear, shook the tower.

Mom yanked off her phones,  

And with all she could muster  

Logged a spot of the signal  

On the DX PacketCluster,

While I ran to the window  

And peered up at the sky,  

To see what could generate  

RF that high.

It was way in the distance,  

But the moon made it gleam -  

A flying sleigh,  

With an eight element beam,

And a little old driver  

Who looked slightly mean,  

So I though for a moment  

That it might be Wayne Green.

But no, it was Santa,  

The Santa of Hams,  

On a mission this Christmas  

To clean up the bands.

He circled the tower,  

Then stopped in his track,  

And he slid down the coax  

Right into the shack.

While Mom and I hid  

Behind stacks of CQ, 

This Santa of hamming  

Knew just what to do.

He cleared off the shack desk  

Of paper and parts,  

And filled out my late  

QSLs, for a start.

He ran copper braid,  

Took a steel rod and pounded  

It into the earth  

Till the station was grounded.

He tightened loose fittings,  

Re-soldered connections,  

Cranked down modulation,  

Installed lightning protection.

He neutralized tubes  

In my linear amp...  

(Never worked right before –  

Now it works like a champ).

A new low-pass filter  

Cleaned up the TV.  

He corrected the settings  

In my TNC.

He repaired the computer  

That wouldn't compute,  

And he backed up the hard drive  

And got it to boot.

Then, he reached really deep  

In the bag that he brought,  

And he pulled out a big box.  

"A new rig?" I thought!

"A new Kenwood? An Icom?  

A Yaesu, for me?

An Elecraft, TEN-TEC

Or Flex, could it be!"  

(If he thought I'd been bad  

It might be QRP!)

Yes! The Ultimate station!  

I suddenly got nervous?  

Could it be all those weekends

I worked Public Service?

He hooked it all up  

And in record time, quickly  

Worked 100 countries,  

All down on 160.

I should have been happy.  

It was my call he sent.  

But the cards and the postage

Will cost a month's rent!

He made final adjustments,  

And left a card by the key: 

"To Gary, from Santa Claus. 

Seventy-Three."

Then he grabbed his HT, 

Looked me straight in the eye, 

Punched a code on the pad, 

And was gone - no good bye.

I ran back to the station, 

And the pile up was big. 

But a card from St. Nick  

Would be worth my new rig.

Oh, too late, for his final

Came over the air.  

It was copied all over. 

It was heard everywhere.

The Ham's Santa exclaimed

What an old ham expects: 

"Merry Christmas to all, 

And to all, good DX."

© 1996, 2016 Gary Pearce KN4AQ 

And here is a previous post from Christmas 2017:

https://ve7sar.blogspot.com/2017/12/a-hams-night-before-christmas.html

Back To Basics: Voltage Measurement

How is a voltmeter usually connected to a circuit under test?

Question B-005-013-001 - From The Canadian Basic Question Bank

A handy thing to know, particularly as basic digital multimeters (DMMs) are now very inexpensive, usually less than $10., and can be useful for many things around the home like checking the condition of batteries.

The two types of voltmeter you may encounter are digital and analog.  Analog meters are recognizable by their printed scale and a moving needle. 

Voltage is always measured in parallel with a device, current in series. If you recall Ohm’s Law in your (Canadian) Basic Qualification, you will remember series, parallel and series-parallel circuits. If not, check this link:  http://www.physicsclassroom.com/class/circuits/Lesson-4/Two-Types-of-Connections

On the meter, first set the knob to a voltage range greater than the expected voltage. If you don’t know what to expect, set it to the highest range.  DC Voltage range has a V- with a straight line next to it, AC generally a V~ with a wavy line. For example, 2V measures voltages up to 2 volts, and 20V measures voltages up to 20 volts. In our circuit the meter is hooked up in parallel to measure the voltage of the component under test.

The correct answer therefore: In parallel with the circuit.

~ John VE7TI