Well, it took a super-human effort on my part as a result of my extreme fatigue (brain bleed issue) but today I bench tested the little 40m Pixie kit I managed to build earlier this week. It is hard to explain just how exhausting this simple task was for me currently. I now need to recover my energy!

On receive a 1uV signal was perfectly readable and I could detect carrier on/off down to at least below 0.5uV. On TX it was putting out about 250mW into a 50 ohm load. On my antenna it was suffering some AM breakthrough, but less than I was expecting. I was using standard Walkman stereo headphones and a rechargeable 12V sealed lead acid battery. On a small 9V battery I’d expect about 100mW RF out, although this was not tried.

Overall, these results exceeded my expectations: it is more sensitive than I was expecting and the breakthrough of AM broadcasters is certainly OK in the day time. This is of course with no casing at all and no ATU. Using the fitted pot and fitted 1N4001 as a varicap it is easy to get the TX frequency and RX frequency to correspond, often an issue with very simple QRP rigs.

Next stage will be some on-air tests, but it most definitely works. Working the locals should certainly be possible. Sked with G6ALB (3km) arranged for 1000z Sunday on 7.023MHz CW.

UPDATE 2120z:  There is a contest in full swing and several Russians and Asiatic Russians copied on the little 40m Pixie. I did not stay on long but there was no apparent BC interference noticeable. So, on a quiet night I should able to use the rig in the evenings. The main issue on RX seems to be the lack of AF filtering, so one has to use “the filter that is between the ears” i.e.the brain.

Roger Lapthorn, G3XBM, is a regular contributor to AmateurRadio.com and writes from Cambridge, England.

From the World Radiosport Team Championship (WRTC) website:

The World Radiosport Team Championship (WRTC) is a competition between two-person teams of amateur radio operators testing their skills to make contacts with other Amateur Radio operators around the world over a 24 hour period. All teams use identical antennas from the same geographic region, eliminating all variables except operating ability.

WRTC2014 included 59 competing teams from 29 qualifying regions around the world. Competitors represented 38 different countries.

This is a unique contest in that the stations used are roughly identical so that operator skill is the main variable. I love watching these guys work the radios, especially the CW ops. Even if you are not a contester, take a look at this excellent video and enjoy radio hams having fun messing around with radios.

WRTC 2014 Documentary from James Brooks on Vimeo.

The post 2014 World Radiosport Team Championship 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].

This article follows up on this one. The title could also be: doing measurements on hand held radios is hard. Actually, some measurements I did in the past might not be so accurate after all.

Measuring in dBm
If you measure in dBm, what I always did, you assume that the device at the other end is 50 Ohms, just like the manufacturer promises you in the specs. Slowly but surely we are finding out that this is not always the case. As a result I might have to switch to microvolt (µV), a method which doesn’t require a perfect 50 Ohms at the other end.

Can’t we just convert it? 0.5 µV @ 50 ohms = -113 dBm, a piece of cake, right? No. You must know the actual impedance of the receiver if you want to convert from dBm to µV. Erik PE1RQF did some measurements on a few hand held radios to find out the true impedance. The outcome was, well, a bit scary.

What this means for us
What this outcome basically means is that generating cold numbers on sensitivity and antenna performance are nice, but don’t tell the whole story, or could be misleading.

• Antennas which prove to be the best performers (RX/TX, VSWR), tested under optimal conditions, are not necessarily the best performers on a specific brand/model of hand held radio.
• There are antennas which aren’t 50 Ohms at all, but could very well outperform everything else on the market because your radio isn’t 50 Ohms either.

Do the test yourself
The best example I can give you is this one: take a Baofeng BF-666S, 777S or 888S, use the stock antenna, and make notes of the performance in the field. Try to hit repeaters which are barely in range. If you have a field strength meter, measure field strength when transmitting.

Remove the stock antenna and replace it by a Nagoya NA-701, NA-771, the $3.79 antenna, or the Baofeng UV-B5 antenna. I tried all of these; just pick whatever 3rd party antenna you have. Repeat the tests.

What happened here is that the short stock antenna was the best of the bunch, all 3rd party antennas had a negative influence on the performance of this specific Baofeng model. The same 3rd party antennas mentioned above did improve the performance of the Baofeng UV-5R, often by a wide margin.

Exception to the rules
The funny thing is that reception suffered greatly too. This is quite uncommon and a sign that hand held radios don’t follow the rules. For example, if you just want to receive on 20 meters and your dipole is 2×6 meters instead of 2×5 meters, you would never notice the difference. With your hand held radio however you will.

Hans, PD0AC, is a regular contributor to AmateurRadio.com and writes from Almere, The Netherlands. Contact him at [email protected].

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.

With the recent quieting of the geomagnetic field, resulting in K values of 0's and 1's, along with a positive-going DST value, the broadcast band on Wednesday and Thursday night was much more vibrant than it has been in several weeks.

Being located on the eastern shoreline of Mayne Island, the direction towards all of the U.S.A. is over many miles of saltwater, so my main interest is in domestic / U.S.A. DX.

Wednesday evening netted two new states on the BCB ... Kansas and Indiana, for states #27 and #28 respectively, both heard on the Perseus SDR and my 10' x 20' amplified loop.

KWOD, on 1660KHz, identifying as "The Business Channel", was logged during a short top-of-the-hour fade-up at 0600z (10PM local time). Their night power is listed as 1,000 watts while their day power is 10,000 watts.

KWOD - Kansas courtesy: https://www.google.ca/maps

KWOD Towers courtesy https://www.google.ca/maps

The transmitter site is located in the middle of a quiet residential district of older homes ... on all four sides.

I shudder to think what RFI problems those living in the adjacent homes must suffer when they are on daytime power!

WSLM - Indiana courtesy :https://www.google.ca/maps

WSLM, on 1220KHz, was also logged at 0600z, during a two-minute fade-up and in the middle of the local weather report.

Interestingly, the station's night-power is listed as "82 watts", which, judging by the readability of their signal, was not the case. Perhaps the engineer just 'forgot' to switch from their daylight power of 5,000 watts!

Their phased antenna array puts their main lobes, due east and west, so evidently I was catching the northern edge of their pattern.

courtesy: https://www.google.ca/maps

See what you can hear their during the short recording made of  the "Country WSLM" weather report





I have yet to check last night's recordings to see if conditions have held-up for two night's running ... more later if so.
Steve McDonald, VE7SL, is a regular contributor to AmateurRadio.com and writes from British Columbia, Canada. Contact him at [email protected].

This is the Pixie’s “big brother”. I have mentioned it before in this blog. It has more power than the Pixie and a better RX. Best of all it costs just over £15 built with free shipping from Hong Kong.

See http://www.ebay.co.uk/itm/Frog-Sounds-HAM-Radio-QRP-Kit-Telegraph-CW-Transceiver-Receiver-Radio-Station-V3-/251405614850 .

Roger Lapthorn, G3XBM, is a regular contributor to AmateurRadio.com and writes from Cambridge, England.

Yesterday I found my rechargeable 12V battery and charged it up. I also checked the Pixie I built as a kit for dry joints and shorts. As all looks good, I hope to test this on the air over the weekend or early next week.

There are a couple of locals I’d like to test with initially, although I am expecting to suffer from AM breakthrough mainly from broadcast stations very close to our 40m band. Probably there would be less breakthrough in the daytime? My antenna is short and low on 40m (a Par triband end-fed covering 10m/20m/40m) so any contacts will be good!

I can test it first on a signal generator and then a power meter. If it works, I’d expect a sensitivity of around -100dBm and a power out of around 200mW on 40m. We’ll see. Even -80dBm and 100mW would be enough to work locals as long as AM breakthrough is at a manageable level.

Roger Lapthorn, G3XBM, is a regular contributor to AmateurRadio.com and writes from Cambridge, England.