Sunday, April 23, 2017

Coming soon: a balloon-optimized transmitter from G0UPL

Flight data encoded onto JT65 transmission
Hans G0UPL recently announced that he is making progress on a lightweight version of his Ultimate 3S multi-mode transmitter. The U3S is a QRP beaconing transmitter that can operate WSPR, JT9/65, PSK, CW and a great number of other modes from LF to VHF.

Dave VE3KCL has used stripped-down versions of the U3S in a number of balloon flights including several that have circumnavigated the world. His balloons are simply mylar party balloons available just about anywhere at a very low price. He uses his own firmware loaded into the controller and powers it with tiny solar cells like these that weigh less than half a gram.

Thursday, April 20, 2017

100 milliwatts

If nothing else, WSPR is great at detecting band openings that might otherwise go unnoticed. The 20m band seems to be dead most of the time but a low-power WSPR session sometimes reveals surprises.

What's surprising here (at least to me) is that during the following session, numerous European stations were monitoring the band and not a single one of them heard me. But I was heard long-path by the VK's and at my antipode by 3B8IK.

Output power was 100 milliwatts with my (solar powered) Raspberry Pi to a 2-element Yagi up 17 meters pointed toward EU.



Saturday, April 15, 2017

Monday, April 10, 2017

Wizkers for the KX2 - don't waste your money

I've had Wizkers on my Samsung Tab 2 for quite a while now and was waiting for a few bugs to be cleared up before trying it. The online Wizkers forum recently indicated that a bug had been fixed regarding the freq display of the animated KX2 in the Wizkers app.

Configuration is as close to automatic as you can get and involved nothing more than attaching my KX2 to the tablet using an OTG adapter and the cable that ships with the KX2. Open the app, select "KX2" and the default values. "OTG" showed up in the 'Connect via' field.

Once I did that, I could see some of the KX2's values...but only some of them.

Selecting the band via the app worked. I could also change filter bandwidths, AF level and other parameters on the KX2 and see those changes reflected on the Wizkers display. The reverse worked as will - I could control the KX2 by manipulating the app.

I called CQ on 14.060 and got an answer from KA9DCU (who was QRP with an LNR LD-11). During the QSO, I could see the dynamic graph of my power out. Cool.

But what I wanted to see was the changing temperature on the "PA Temp" graph but it read zero the entire time, not even registering the ambient temp. Same for the supply voltage graph - zero. And the biggie, the freq display on the app - it reads all 8's, all the time.

Despite my efforts I honestly can't find a use for this app. It seems to serve no real purpose other than generating a bit of income from gullible buyers like me.


Sunday, April 9, 2017

Tuesday, April 4, 2017

ARRL's review of Elecraft KX2 and LNR MTR-3B QRP transceivers now available

The May issue of QST will feature detailed reviews of the KX2 and the KD1JV-designed MTR-3B. Subscribers should have the issue in their mailboxes in a couple of weeks.

But no need to wait. The reviews are online right now as a 6.5 MB pdf file downloadable by ARRL members. I was quite interested to read each review since I own both of these rigs and am amazed by their performance. It's nice to see my praise validated by lab numbers.

Not surprisingly, the review of the KX2 is quite favorable - and deservedly so.

I was, however, pleasantly surprised to see the detail of the review for the MTR-3B. Small QRP kits such as this one have usually been the subject of only brief reviews, if at all. The lab guys at the ARRL put the tiny rig through the full suite, testing blocking dynamic range, spectrum, keying characteristics and more.

In short, they treated it like a Big Boy.

Friday, March 31, 2017

New rig for 630-meter allocation

(1 April 2017) Far ahead of other ham gear manufacturers, Amertron saw the writing on the wall and has now released the VLF-630 for sale to US amateurs who want to hit the airwaves on the new 630-meter band.

At a press conference held at their headquarters in Bleaksville, Mississippi, Amertron spokesperson Eurasmus B. Large explained that innovation and being first at the gate with new technology were of paramount importance for any company's viability in such a competitive market.

Although details are still uncertain, the VLF-630 is believed to contain cutting edge technology for this new low-frequency band. Some specifications: