VK2RH ham radio

Category: Portable

  • New KD1JV ultralight rig for 80/160

    There’s been a higher than usual level of activity on the AT-Sprint email list over the last few days as  hints have emerged of a possible new offering of the popular MTR (Mountain Topper Radio) the latest of Steve Weber KD1JV’s radios that define the possibilities of ‘trail friendly’. To get a view of one in action check out this video from G4ISJ shot on a SOTA activation.

    Steve KD1JV’s popular MTR ‘a very small, very efficient, two band rig’ is set for another future offering

    Steve KD1JV is the designer behind the PFR-3 and a number of other radios offered by Doug Hendricks’ QRP Kits along with the new Tri-bander Transceiver kit. But he also enjoys a passionate following for his high performance but tiny (Altoids tin size) radios in the ATS series where ATS stands for Appalachian Trail Sprint. These radios (especially the ATS-3B and the MTR) are prized by ham hikers and walkers who watch the ounces and milliamps. They are also an example of masterful interface design using small push buttons and minimal LED display. As Steve mentioned recently in a post reflecting his deep field operating experience “Little tiny rigs and knobs don’t work well together”.

    During the buzz earlier today about whether he would offer more of the MTR kits (he will), Steve also announced his latest project “An 80/160 dual band rig with direct conversion receiver and a DDS/PLL hybrid VFO using all through hole parts.” (The ATS series made extensive use of microscopic SMD components and lots of the assistance Steve offers via the AT Sprint Yahoo group is concerned with discovering and rectifying makers’ errors assembling these devices.)

    His website carries a pretty detailed three-page description of the design thinking behind the new rig which he’s calling the Super Deluxe Direct Conversion Transceiver. Tantalisingly he’s suggested it may be able to work at 500kHz. The new rig also features an “LCD frequency read out, built-in keyer and rotary tuning”.

    He’s planning to offer only 50 kits at about US$75 at the end of November. Expect to see them sell out in two minutes! I suspect if he offered 200, they might last an hour or two.

  • Ultraportable Elecraft KX3

    UPDATE: Steve G4GXL’s 10 minute YouTube video of Wayne N6KR’s quick overview of the new KX3 is available from http://qrparci.org. Also there are early photos on Twitpic here – courtesy of Jeff Davis KE9V including this one:

    One of the earliest – and clearest – photos of the new KX3 taken at the Elecraft stand in Dayton by Jeff Davis KE9V

    Under the tantalising subject line “Something *really* new at Dayton from Elecraft” and while en route to Dayton – Elecraft’s Wayne Burdick N6KR announced to the Elecraft email lists a very interesting new offering to be launched there – the KX3 and a companion 100W amp, the KXPA100.

    According to Wayne, the KX3 handles all modes, SSB/CW/AM/FM/DATA (the latter including built-in PSK31 and RTTY encode/decode/display).

    He promised to post full details and photos later this weekend. But that was too intriguing for the list. This is an edited and probably repetitive summary of what they managed to find out about the new set.

    KX3: Ultra-compact K3/KX1 hybrid, 160-6 m, 10/100 W, all-mode, 32-bit DSP/SDR, 1.5 lbs.

    Ultraportable:

    • 1.5 lbs (680g)
    • 1.7″ x 3.5″ x 7.4″ (4.3cm x 8.9cm x 18.8cm)
    • extended KX1 form-factor (KX1 – 1.2 x 3 x 5.3″ (3 x 7.5 x 13 cm) KX1 base weight 9oz / 255g)
    • internal battery pack & charger
    • internal wide-range ATU
    • new adjustable, attached keyer paddle

    …and a K3-like front panel, including the same LCD.

    RX-mode current drain ~150 mA. Very efficient on TX, with dual-output-impedance 5W/10W PA.

    The optional 100W amp is in an external chassis. The internal amplifier is 10W with switchable impedance matching so it can also operate with maximum efficiency at 5W.

    PA output impedance switch allows efficient 5-W use from internal batteries, or 10 W from external supply.

    KXPA100 – 100 W+ with new high-performance external amp/ATU that works with most 5W to 10W rigs.

    >Same flat layout as the KX-1 – just bigger box I would assume????

    Yes, but with new fold-up rear tilt-feet.

    >…and a K3-like front panel, including the same LCD.
    >
    > And it makes use of EVERY display on that LCD?? Carumba!

    Not quite. I think there are a couple annunciators that are not used. But it’s amazing that the design team managed to fit almost all the features of a 10W K3 into a box that is a small fraction of the size and weight. And with space left over for an internal battery pack!

    By the time we’re done, we’ll be using every icon.

    Totally different architecture than the K3, of course. (Wayne N6KR)

    RX-mode current drain ~150 mA. Very efficient on TX, with dual-output-impedance 5W/10W PA.

    > More $$$ or less $$$ that the regular K3?

    Much less.

    > Dual output impedance 5w/10w pa? I don’t understand.

    The MOSFET 10-W amp stage includes an output transformer with both 1:4 and 1:1 windings. When using low power, or when running from internal batteries, the 1:1 winding is used, which optimizes efficiency at about 5 W, greatly reducing transmit current drain. The 1:4 winding is used when running higher power (using an external supply).

    > One email said 10w/100w models. Is that correct?

    The 1.5-pound radio itself puts out 10 watts+. We’ll also be describing a new, high-performance 100-watt+ companion amplifier/ATU for fixed-station/mobile use. It will work very well with other 5 to 10-W radios besides the KX3.

    From follow-up discussion etc it appears as if the base price of the KX3 will be US$799. Availability towards end of 2011. See video for a pretty comprehensive outline of features. Options for the KX3 include roofing filters, internal battery pack and ATU similar to one of K3. Truly an exciting trail friendly radio!

    I’ve created a page where I’ll pull together all the available information there is about this ultimate trail friendly radio.

  • A123 batteries

    There’s been a great explanation posted on the Buddipole list about the practicalities of using the A123 battery packs Buddipole sell from their site.

    A123 4S2P battery

    The advantages of the A123 chemistry are low weight, fast charge times and ability to deliver high current. As well their voltage – 13.2v for a four cell pack such as the one shown – is well-suited to modern amateur radio gear.

    The email exchange is yet another example of how an innocent newbie’s question can draw out the best information which benefits the broader group. Mark KD5RXT’s explanation of duty cycle and the unique qualities of this new battery chemistry are almost text-book ready!

    I’m still keen to find out more about the selection of the best solar cell and charger system to keep such a battery topped up. I sense that a system that could take advantage of its fast charge rate might dwarf the rest of the radio gear. And I also sense that current portable solar panels, especially the expensive roll-up ones might barely keep track even at QRPp levels.

  • iPad date announced for Australia

    News this morning from Apple that the delivery date for iPad (both WiFi & 3G) – in Australia – is 29th May.

    The new Apple iPad

    I’m so looking forward to seeing how an iPad might fit into a portable QRP operation. Or even a remote one. I’m also hoping that Apple will retain enough of open protocols so that the device does not simply become an expensive personal front end to whatever shops they wish to set up, like the sadly not ready for primetime Kindle.

    Lack of a camera on the iPad is odd – given the next iPhone will actually have two – one in the front as well as the existing one on the back. Bluetooth keyboard sounds like it could be fun. I also imagine that ham radio apps to track satellites (ProSat) and monitor solar activity (Space Wx, 3D Sun etc) should look amazing. A work colleague showed me his new Android phone with a graphically brilliant astronomy application that you could use to locate, stars, planets and constellations easily. It felt like visual velvet and the images were much richer than I’ve seen so far on the iPhone.

    Even a straighforward app to display bandplans should be able to be made to look clear and brilliant and enable you to get different views depending on mode, QTH or licence class.

  • CW and the missing link

    How the Palm mini paddle can stow away – perfect for portable operation.
    How the Palm mini paddle can stow away – perfect for portable operation.

    I’ve been keen on finding out more about the Palm mini paddle. I like the look – and the size – of the paddle. I haven’t worked out yet if there’s a way to strap it onto your leg, but it certainly doesn’t seem to require too much in the way of real estate.
    I also like the design style of this line including the modular keyer, the “code cube”.
    Most impressive of all is the Infra Red link technology they’ve incorporated into the line. It looks like you can purchase an IR enabled Code Cube to plug into an existing Mini Paddle so you can link up via an IR receiver connected to your transceiver, or even a tiny sensor within the txrx – up to 5 metres away.
    Marshall Emm’s Morse Express seems to be the most accessible distributor. The site hosts extensive info including the pdf manuals, which can also be found on the German site.