Indication versus measurement

The nature of a technical hobby gives way to the ‘buying of stuff’. Sometimes this is the tool required to carry out the crux of the hobby, in our case I’m referring to the transceiver. Sometimes this is the tool required to check that the main tool is working correctly, in our case this could any number of tools such as an antenna analyser.

There are also many hams that like to buy the box, or series of boxes and do the minimal amount of testing to ensure safe operation and there are those that will only operate what they have built themselves. Most of us fit on that spectrum. I certainly do, it just varies on what I’m doing.

For longer than I care to admit I have used an antenna analyser that belongs to my local club. It is free to be loaned but I’ve used it more than my fair share of times. I also like to build the odd antenna. This means I measure the length and then cut the wire and check it’s various characteristics and generally cut it again until I’m happy that I have a suitable compromise. Its a really useful tool. I assume its quite accurate because it cost a lot. But do I really need it?

Separating needs from wants is not that easy, partly because what starts out as a want can quite easily become a need. I made a decision recently, I was going to buy my own analyser. But which one? Que the usual looking through specs and performance criteria, guess what happened next. I started with a small requirement for a HF analyser and ended up looking long and hard at analyser >£300. Reflecting on this it becomes easy to bump up the needs because I never really noted down what I actually wanted.

So what did I actually need? In this case I wanted to ensure that I wasn’t going to damage a transceiver and transmit spurious rubbish (as opposed to my usual cw rubbish). So I didn’t really need a tool to measure, I needed a tool to indicate. But ah ha, I still needed to cut the antenna to the right length, so I did need something to measure but did it need to be really accurate?

It turns out it didn’t. It’ll be a good idea to get a rough idea but to 3 decimal places? nope, it just isn’t that important. So I duly purchased a cheapo SARK analyser off ebay for around £30 and it’s allowed me to measure and get the right length(s) (I built a multiband end fed antenna this time) and use a cheapo end fed tuner and the analyser to get the correct swr and impedance for safe and fairly optimised operation.

The lesson learned is that if I don’t set out the requirements first then I’m going to end up spending 10 times on a product that I probably don’t need.


Alex Hill, G7KSE, is a regular contributor to AmateurRadio.com and writes from Cumbria, UK. Contact him at [email protected].

Ham College 43

Ham College episode 43 is now available for download.
General Amateur Radio Exam part 14. Emergency Communications, Skywaves, Yagi Antennas.

53:58

Download
YouTube


George Thomas, W5JDX, is co-host of AmateurLogic.TV, an original amateur radio video program hosted by George Thomas (W5JDX), Tommy Martin (N5ZNO), Peter Berrett (VK3PB), and Emile Diodene (KE5QKR). Contact him at [email protected].

Technician License Class – Black Forest, CO

Time: Saturday Sept 15 and Saturday Sept 22 (8 AM to 5 PM) 2018

Location: Black Forest Fire Station 1
(intersection of Burgess Rd. & Teachout Rd., Black Forest, Colorado)
Sponsored by the Tri-Lakes Monument Radio Association

The FCC Technician license is your gateway to the world-wide excitement of Amateur Radio, and the very best emergency communications capability available!

  • Earn your ham radio Technician class radio privileges
  • Pass your FCC amateur radio license exam right in class on the second day
  • Multiple-choice exam, No Morse Code Required
  • See live equipment demonstrations
  • Learn to operate on the ham bands, 10 Meters and higher
  • Learn to use the many VHF/UHF FM repeaters in Colorado
  • Find out how to participate in emergency communications

For more background on ham radio, see Getting Started in Ham Radio.

Registration fee: $30 adults, $20 under age 18
In addition, students must have the required study guide:

HamRadioSchool.com Technician License Course
New Edition, effective 2018 – 2022, $22.95

Advance registration is required (No later than one week before the first session, earlier is better, first-come sign up basis until class is full.)

To register for the class, contact: Bob Witte KØNR
Email: [email protected]

The post Technician License Class – Black Forest, CO appeared first on The KØNR Radio Site.


Bob Witte, KØNR, is a regular contributor to AmateurRadio.com and writes from Colorado, USA. Contact him at [email protected].

Amateur Radio Weekly – Issue 212

Significant changes in store for FT8 and MSK144
Enhanced versions of the MSK144 and FT8 protocols will extend the message payload to 77 bits.
ARRL

ISS SSTV activation July 30-31
The Russian cosmonauts on the International Space Station are expected to activate amateur radio Slow Scan Television (SSTV) transmissions.
AMSAT UK

Why wire diameter is important
The larger the cross-sectional area of the conductor, the more electrons are available to carry the current.
VE7SAR

3D printed Arrow II portable satellite antenna clips
WI9LL has designed clips for use with the Arrow II Portable hand held satellite antenna.
WI9LL

Operating tips for VHF SOTA
I’ve been using VHF and higher frequencies for SOTA exclusively and have activated over 100 summits in Colorado and other states.
K0NR

FCC proposes $18,000 fine for Ham in interference case
“Given his history as a repeat offender, these apparent violations warrant a significant penalty.”
ARRL

A visit to the home of FreeDV and codec2
I knew I was in the right place when the squid pole supporting a corner dipole came in to view.
Marxy

WWFD in AM HD
America’s only AM HD station.
The SWLing Post

Is your repeater ID boring? Try something like this.
If your repeater ID is getting a little stale, perhaps this will give you some ideas on how to freshen it up a bit.
KB6NU

Receiving astronaut Amateur Radio conversations with an RTL-SDR
If you live in an area that can ‘see’ the ISS at the same time as the school then you can easily pick up the downlink.
RTL-SDR.com

Send APRS data/telemetry via Xastir command line
You can do it all via RF if your Xastir setup is already paired to the radio and configured to transmit.
S55MA

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Amateur Radio Weekly is curated by Cale Mooth K4HCK. Sign up free to receive ham radio's most relevant news, projects, technology and events by e-mail each week at http://www.hamweekly.com.

Hunting For NDBs In CLE 234



This coming weekend will see the 'Barn Door' CLE, mentioned in a previous blogspot here. Listeners are required to challenge themselves by listening on a receiver using a wide enough bandwidth that several kHz worth of signals can be heard at once.




The 'immersive' effect this wider bandwidth mode provides is much different than when listening with narrow filters and can make digging out IDs a lot more challenging. Throwing in some mid-summer lightning noise makes it even tougher, but if it were easy, it just wouldn't be much fun!

Many, including myself, will be using homebrew single MOSFET regenerative receivers, often called a '1AD' since they normally use just one active device. I've just finished testing my own version and have been able to hear some night time DX so hopefully the band will be quiet enough to hear some signals during the CLE.

From CLE organizer Brian Keyte, here are the details explained ... and good luck to all participants!

Hi all

It is an opportunity to bring back to life basic kinds of receiver - anything with low selectivity which allows you to hear NDBs on several frequencies simultaneously - leaving the barn door wide open!

Listening with 'back to basics' equipment often gives very satisfying and unexpected results.  It can also show us ways of improving our listening when operating more normally.

Our last Barn Door CLE was No. 209 in July two years ago.

Here comes our fifth 'Barn Door' CLE.  Between us there will be a great variety of different receiver types in use.

    Days:      Friday 27 to Monday 30 July 2018
    Times:    Start at  ## 11 a.m. on Friday 27th, your LOCAL time
                   End at   ## 3 p.m. on Monday 30th, your LOCAL time
    Frequencies:   Centred on 360 kHz (see below)
    NDBs:     NOT MORE than 100 'normal' NDBs including any UNIDs
                   (That is not intended to be a target to reach)

We are all asked to listen with NON-SELECTIVE receivers - i.e. with a WIDE
filter or NO filter.  Your 'barn door' should be open wide so you could
hear, at the same time, any NDBs 2 kHz away on both sides of your receiver
setting - E.g. NDBs on 348, 349, 350, 351 and 352 kHz with the receiver set
to 350 kHz.

## The extra daytime hours on the first and the last day might help some of
us planning to listen out of doors.

You could listen with:

1. A simple home-made receiver, such as a single transistor set with regen.
    (e.g. based on the sets used by Mike, Finbar and others).

2. OR - an Ultralight receiver, maybe one converted to cover the NDB
    frequencies with a modified aerial.

3. OR - an 'antique' receiver (e.g. Eddystone, R1155, Scott, etc.)
    Perhaps you have something you've not switched on for many years?

4. OR - a normal receiver but with NO filtering, or using a WIDE FILTER,
    (not less than about 2 kHz and no selection of an audio filter).

You choose how wide a RANGE of frequencies you will listen in, CENTRED ON
360 kHz.  You could choose 350-370 kHz or 330-390 kHz or 260-460 kHz, etc.
   (This allows each of us to choose a +/- range with enough NDBs to
   match our equipment's capability.  It will also allow our loggings to
   be compared in the Combined Results, at least around 360 kHz).

Logs should show NOT MORE THAN 100 NDBs please (if more than 100, the
harvester program will 'drop' the loggings furthest from 360 kHz).

There are several extra targets you could set yourself - maybe the wide
bandwidth, the centre frequency of 360 kHz and the 100 loggings limit do not
challenge you enough!


You could listen only in daytime and/or away from home.
Or how about NDBs on 360 +/- 10 kHz or even +/- 5 kHz?
The Twente remote receiver in Holland could be interesting to use for the
whole of your (only) CLE log.

( Go to http://websdr.ewi.utwente.nl:8901/ and read the advice there:Select AM and 'MAX IN', enter e.g. 354.7 in the frequency box and change the
filter's limits to 2 or 3 kHz from the centre frequency on both sides )

We’ll summarise everyone's equipment on the first page of the combined
results, so please describe:
The RECEIVER/AERIAL you used and the FILTER(s) selected, if any.
If homebrew, please quote:  the total number of active devices used –  e.g.
1 for a single transistor stage ( 1AD ) -  the transistor/valve types,
whether using regen.,  etc.

All the usual procedures for making logs apply:

Send your CLE log to NDB List, if possible as a plain text email and not in
an attachment.

Please show on EVERY LINE of your log:
    # The full date (or Day No.) and UTC (the day changes at 00:00 UTC).
    # kHz - the beacon's nominal published frequency, if known.
    # The Call Ident.


Show those main items FIRST on each line, before other optional details
such as Location, Distance, etc.  Please send your complete log with
CLE234 and FINAL  in the Subject line.

Whether you are a first time CLE-er or a regular, make your log interesting
to everyone by showing your own location and your equipment details.
Do feel free to share any comments you have on this unusual event.

Joachim or I will send the usual 'Any More Logs?' email at about 17:00 UTC
on Tuesday 31st so that you can check that your log has been found OK.
Make sure your log has arrived on the List at the very latest by 08:00 UTC
on Wednesday 1 August.   We hope to complete making the combined
results a day or so later.

However you choose to take part, we hope you will find your 'back to basics'
listening enjoyable and worthwhile.


P.S.   NOT FOR YOU?

Listening without narrow filters is not going to revolutionise our hobby!
But there ARE some unexpected benefits and advantages:

1. Hearing several beacons on a few adjacent frequencies at the same time
becomes easier as you get practice at recognising them by listening to their
very different audio tones. At first, when listening to a random frequency
setting, you may hear just one or two beacons. But after listening for a
little while you realise that there are three - - four, maybe more, all of
them audible without altering any of the receiver controls.
It is a skill that gives satisfaction as you improve.

2. Hearing multiple beacons like that can be useful because, with no extra
tools, you can hear NDBs over a wide frequency range much more quickly than
usual, perhaps spotting the arrival of new UNIDs or the return of occasional
beacons.  (To protect your hearing, keep your receiver gain controls fairly
low, except on very quiet frequencies).

3. With normal listening it is easy to miss any NDBs that have abnormal
carrier frequencies or non-standard offsets.  With 'Barn Door' listening
they won't escape because everything is let through.

4. When using a wide filter, you may be surprised by hearing some Broadcast
Station signals (e.g. harmonics) among the NDBs and you will be able to
identify them.
With a narrow filter, often you may not recognise an AM signal as audio
- it just sounds like nondescript 'hash' affecting a wide range of
frequencies around the central carrier.


Maybe listeners will report some other good things about their barn door
listening during the CLE - and probably some bad things too!

Do join in if you can.


   Brian
----------------------------------------------------------
From:   Brian Keyte  G3SIA          ndbcle'at'gmail.com
Location: Surrey, SE England         (CLE coordinator)
----------------------------------------------------------

Don't forget that help and chat regarding NDB DXing can be had on the ndb group list here.




Steve McDonald, VE7SL, is a regular contributor to AmateurRadio.com and writes from British Columbia, Canada. Contact him at [email protected].

LHS Episode #238: Open Research Institute Deep Dive

Welcome to Episode 238 of Linux in the Ham Shack. This time around we have an in-depth interview with Steve, AI4QR, and Michelle, W5NYV about Ubuntu Hams and the Open Research Institute. Discussion revolves around the two organizations, their focuses, directions, resources and active projects. Thanks so much to our guests and we hope you enjoy the program.

73 de The LHS Crew


Russ Woodman, K5TUX, co-hosts the Linux in the Ham Shack podcast which is available for download in both MP3 and OGG audio format. Contact him at [email protected].

Weekly Propagation Summary – 2018 Jul 23 16:10 UTC

Weekly Propagation Summary (2018 Jul 23 16:10 UTC)

Here is this week’s space weather and geophysical report, issued 2018 Jul 23 0031 UTC.

Highlights of Solar and Geomagnetic Activity 16 – 22 July 2018

Solar activity was very low throughout the period. Region 2716 (N16, L=199, class/area=Axx/10 on 21 Jul) was briefly the sole active region with sunspots, but was largely unproductive. No Earth-directed CMEs were observed this period.

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit reached moderate levels on 22 Jul with normal levels observed through the rest of the period.

Geomagnetic field activity was quiet to unsettled on 16-17, 20-21 Jul with generally quiet conditions observed throughout the remainder of the period. The activity on 20-21 Jul was associated with the weak influence of a positive polarity coronal hole high speed stream.

Forecast of Solar and Geomagnetic Activity 23 July – 18 August 2018

Solar activity is expected to be very low throughout the outlook period.

No proton events are expected at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit is expected to reach high levels on 23-31 Jul and moderate levels are expected on 01-11, and 18 Aug. Normal levels are expected throughout the remainder of the outlook period.

Geomagnetic field activity is likely to reach G1 (Minor) geomagnetic storm levels on 24 Jul due to the influence of a negative polarity coronal hole high speed stream. Active conditions are expected on 23, 25 Jul and 17 Aug due to the influence of multiple, recurrent coronal hole high speed streams. Quiet and quiet to unsettled conditions are expected throughout the remainder of the outlook period.

Don’t forget to visit our live space weather and radio propagation web site, at: http://SunSpotWatch.com/

Live Aurora mapping is at http://aurora.sunspotwatch.com/

If you are on Twitter, please follow these two users: 1. https://Twitter.com/NW7US 2. https://Twitter.com/hfradiospacewx

– – – – – – – – – – – – –

Be sure to subscribe to our space weather and propagation email group, on Groups.io

https://groups.io/g/propagation-and-space-weather

Spread the word!

– – – – – – – – – – – – –

Links of interest:

+ Amazon space weather books: http://g.nw7us.us/fbssw-aSWSC
+ https://Twitter.com/NW7US
+ https://Twitter.com/hfradiospacewx

Space Weather and Ham Radio YouTube Channel News:

I am working on launching a YouTube channel overhaul, that includes series of videos about space weather, radio signal propagation, and more.

Additionally, I am working on improving the educational efforts via the email, Facebook, YouTube, Tumblr, and other activities.

You can help!

Please consider becoming a Patron of these space weather and radio communications services, beginning with the YouTube channel:

https://www.patreon.com/NW7US

The YouTube channel:
https://YouTube.com/NW7US

..


Visit, subscribe: NW7US Radio Communications and Propagation YouTube Channel

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