Sepura introduce intrinsically safe TETRA portable

My colleagues at my old company, Sepura, have just released details of their new ATEX intrinsically safe TETRA portable. From my own experience of designing intrinsically safe products (PF2UBIIC, EXPF85) this is a far from easy task, especially today when the tests are even more extreme and challenging. Well done to the team involved.

Intrinsically safe radios are designed to be used in very hazardous locations such as oil refineries or petrochemical plants where the risk of explosion is high. They are designed to be safe even in certain fault conditions.

My first JT65 QSO

Although I've listened/looked at received signals with this mode, this morning I had my first ever JT65 QSO (using QRP of course) with EA1YV on 14.076MHz. I used the JT65-HF package with the simplified interface for HF QSOs. It worked a treat. See http://physics.princeton.edu/pulsar/K1JT/JT65.pdf.

As I've no antenna for 20m I just used my 10m halo tuned via the Elecraft T1 auto-ATU.

4m transverter - some builder feedback

Just got this very nice email about my 4m transverter:

Hi Roger,

               My name is Mark (mi0bdz) and I was browsing the net for 70mhz projects when I came upon your site. I could hardly believe the simplicity of the little 70mhz  transverter you designed and built. I decided to copy it. I started on Friday afternoon after gathering the bits together and completed it by Saturday evening. I could not have done this without thanking you for sharing the project,  which I class as the best usable project I have come across in many years.

   I have found that by careful selection of the TX transistors and bias resistors that 3 watts is possible. I did have to alter the values of the bias resistors quite a bit, but that is all. Everything else is as your schematic. Thankyou again for a wonderful little project. This is a gem. The sensitivity is also excellent. You were right about packing a lot into a chip indeed. Thanks again Roger.

  Regards

             Mark

Cycle 24 already peaked?

Check out recent trends - it looks like the present cycle has already passed it's peak. Or is this just a blip?

6m Es

Well, the 6m sporadic-E season is in full swing again: yesterday loads of Europeans worked with QRP and the vertical and this afternoon being spotted in Spain with WSPR. Initially it's fun working around Europe, but as the season goes on the real excitement is further afield looking for US/Canadian and South American stations on 50MHz. It never fails to amaze me how far one can hear/work on 50MHz with the right conditions. Also, next month should see the return of UK-Japan openings on 6m possibly as a result of reflections/scattering from high altitude noctilucent mesospheric clouds; signals with this mode are usually very weak.

Old QSL cards

Clearing the loft today I came across several QSL cards from my first year in Cambridge back in 1971 including this one from Bob G3WKW for a QSO across town using my 1 transistor 2m TX on CW and FM. I cannot recall the details or how I obtained the FM. Power was just a few milliwatts into a dipole in the downstairs room in a terraced house. Bob went on to work for Motorola before retiring in Hampshire a few years ago. We still keep in contact.

137.5kHz WSPR

Several stations on 137.5kHz WSPR tonight. G4WGT is testing a new rig, M0PPP is getting decent reports and me getting reports from just G3XIZ so far. Will leave WSPR running for a few hours and see what happens.

QRSS30 QRPp beaconing on 137kHz band

PA3FNY's reception of the QRSS30 beacon XBM (me)

My QRPp QRSS30 beacon sending "XBM" is active on 137.7679kHz (approx) from now until around 2300z. As before, any reports and screen shots would be much appreciated. ERP is still around 50uW. The last time it was on it was copied in Holland and again today, this time by Victor PA3FNY (see screen shot above) at a distance of 328km.

G3XIZ TXing on VLF today

G3XIZ is active this morning on 8.9766616kHz and clearly visible on the G3ZJO grabber in Northampton. His signal was a lot weaker than the last few times for some reason. I think the difference is at my end.

Bloody-nosed beetle larva in IO80ef square

About 1.5cm long, behaved like a woodlouse.

Walking part of the coastal path in Devon at Prawle Point I noticed this very strange creature in the footpath a few metres from the cliffs. It looked a bit like a fat slightly iridescent woodlouse about 1.5cm long with a very wrinkled outer shell. There is a video of the creature moving at http://www.youtube.com/watch?v=rSDiJA1b1zM . It turns out the creature is the larva of the Bloody-Nosed beetle, which is quite common in the southern UK.