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Ham College episode 79 is now available for download.

Extra Class Exam Questions – Part 17.
E4C Receiver performance characteristics: phase noise, noise floor, image rejection, MDS, signal-to-noise ratio, noise figure, reciprocal mixing, selectivity, effects of SDR receiver non-linearity, use of attenuators at low frequencies.
55:21

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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].

It's time once again for The Weekender. This is our bi-weekly departure into the world of amateur radio contests, open source conventions, special events, listener challenges, hedonism and just plain fun. Thanks for listening and, if you happen to get a chance, feel free to call us or e-mail and send us some feedback. Tell us how we're doing. We'd love to hear from you.

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].

Hello and welcome to Episode 421 of Linux in the Ham Shack. In this episode, the hosts interview Neil Rapp, WB2VPG, coordinator of the IARU Region 2 YOTA camp and Peter Lafreniere, N8JPL, one of the youth participants. The topics include an in-depth look at what the campers experienced, events held, challenges faced, and the future of the event. We hope you enjoy this interview and deep and have a great week until the next time we meet.

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].

This was the first year I took part in the IOTA (islands on the air) contest and I very much enjoyed the time I spent in the contest. It was very well attended and many Island stations were there and waiting to be contacted. I found the band conditions on my end were very challenging at times with stations going from S9 to barley above the noise floor. This is one of the challenges of a contest and just makes things more interesting. I would say it was a nice change to hear lots of stations in the contest, a sure sign that the solar cycle is improving.  As a participant in the IOTA contest you can enter as CW, SSB or both and I choose to enter as a CW op. 

The radio I used was the Icom 7610 with the filter set to 250 Hz with the APF (Audio Peak Filter)  feature turned on. My antenna was an Endfed multiband antenna and my power output was 100 watts. One of the memorable contact I made was Cuba. With all the issues going on there it was nice to be able to make contact with that island. 

I was on the air for about 3 hours in total and made 53 contacts for a score of 5,124. It sure is not a record but I very much enjoyed my time on the radio and that's what it's all about. 

Mike Weir, VE9KK, is a regular contributor to AmateurRadio.com and writes from New Brunswick, Canada. Contact him at [email protected].

Decibels are commonly used in electronic communications to describe and compare signal levels. I’ve often heard that one dB is considered to be the smallest change that a typical person can detect by ear. I recently came across this website audiocheck.net that is set up to generate different audio tones and to do a blind test of how small of a change you can detect.

I started with testing for 6-dB and 3-dB changes. Easy Peasy. Then I tried the 1-dB test. I could detect the change in level fairly consistently but I did have to concentrate. Continuing on to the 0.5-dB change, I had a very high failure rate. It was very difficult to detect that small of a change. So I have to conclude that 1 dB is about the limit for a change I can hear.

How about you? Take the test on the website and let us know how you did.

There are many other audio tests to explore on that site, including the highest frequency you can hear, the minimum pitch change you can hear, etc. Check it out: www.audiocheck.net

73 Bob K0NR

The post Can You Hear a 1-dB Change? 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].

  

They say that hindsight is 20/20 and really no matter what age you are I bet you have looked back on something and would have done it differently. My mom used to tell me that if things went along perfectly you would never have a chance to grow and learn. She was right but some decisions I made looking back if I made them differently the growing and learning would have been faster and easier. But what fun is that eh......If we all had 20/20 hindsight as Amateur radio op's how would things be different? For me, I would not have to purchase AGAIN items that at the time I thought I would never need. Also in retrospect, there were times I sold equipment for the lust of other equipment and in some cases regretted it. 

So what are some of my hindsight 20/20 slash regrets...............selling my first rig it was a Kenwood TS-520SE I had the AT-200 tuner, DG5 digital display and the VFO 520S. At that time it was traded in for a shiny used Icom 745. but in hindsight, I sure wish I had kept it as it was the first rig I had but I do have some nice pictures of it. 

Very early in my years, I had a part-time job at an Amateur Radio store called Hobbytronics (no longer in the biz). It was there I was able to purchase my first brand new rig and yes you guessed it I traded my Icom 745 for a brand spanking new Icom 735. No regrets here but it had me realize the one can trade up to bigger and better! 

At the next point in my ham radio adventures, I drank the Elecraft Koolaid.....I started with the KX1 that I built and was thrilled with it when it worked. I then added the K2 (actually 2 of them) I then took the leap to a K3. The KX1 and K2's eventually were sold and the "ham bucks" were used to purchase needed items like a brand spanking new Elecraft KX3!!!  In hindsight did I need it, no not really at all the K2's were loaded and served me well both at home and portable but I WANTED a KX3. I regret getting rid of both K2's as I built them from scratch and they actually work. 

Then the loaded K3 was sold for my retirement gift to me an Icom 7610. I had great success with the K3 and how it was able to be upgraded via a simple download over the internet. The Icom was the same and it too could be upgraded with the latest and greatest software........WRONG! I found out the hard way that Icom most of the time upgrades to fix issues and not to added new features. To cut Icom some slack they did just this year provide some upgrades but with Icom it's all about the bottom line and not that there is anything wrong with that. So should I had stuck with my fully loaded K3.......yes I think so but hindsight is 20/20

I was comforted in the fact that I still had ONE Elecraft rig in the shack........my trusty KX3 for portable op's and if ever my Icom 7610 went down. Here comes another regret, my PC was old and showing its age. I decided to look around the net to see how I could upgrade my PC and it turned out that this retired guy was a bit short on cash to upgrade the PC to where I wanted it. I was looking at the KX3 and it really was used for portable op's which for the past 2 years never happened. I convinced myself it was just gathering dust (regret) and so I sold it along with its accessories. I was able to use those ham bucks to do a total upgrade of the PC. Looking back it was regret to part with the KX3 but what is done is done and I do have a very nice PC. 

Don't get me started on radio add-on stuff......I have sold more items than I can mention and then purchased them again!!! Ok, let's just list some:

Sold LDG tuner AT 600 and ended up getting LDG 200pro

Sold MFJ 1026 to purchase the same 

Sold Alpha Delta 3 position switch to purchasing the same

LF Engineering H-800 active antenna to purchase the same

LP 100 Telepost meter to purchase CN 901 meter 

The list can go on but to spare me from deep depression :) I will stop here. So what regrets/ 20/20 hindsight decisions have you made and I hope to hear from some of you so I don't feel I am the only one in this boat.

Mike Weir, VE9KK, is a regular contributor to AmateurRadio.com and writes from New Brunswick, Canada. Contact him at [email protected].

 

FT8 waterfall on 10m

Around 19:30 UTC I tuned to 10m and warmed up my JTDX program and I was pleased to see a very busy waterfall. I threw my call in and was answered by some U.S. stations but also the Netherlands with a report of -13. I did have a German op call me but the FT8 gods were not smiling on us and a complete contact was not made. 

PSK reporter had me being spotted in the U.S. and Europe as well. 

Mike Weir, VE9KK, is a regular contributor to AmateurRadio.com and writes from New Brunswick, Canada. Contact him at [email protected].