Welcome to Tropical band

To most people the phrase "tropical bands" bring a pretty clear picture to mind - a bunch of shirtless guys playing calypso music. But to experienced shortwave DXers those two little words express the most challenging and enjoyable part of the radio hobby. The phrase kindles memories of a DXer's best catches and favorite QSLs, of exotic stations, music and of early morning listening sessions. (Don Moore)
I like the "Tropical band" name for new 60m allocation. (OK1RP)

Effective from 1st Jan 2017 please paper QSL via OM-bureau only.


Friday, February 17, 2017

HAARP - QRM nightmare returns...?

The High Frequency Active Auroral Research Program (HAARP) in Gakona, Alaska, will soon undertake its first scientific research campaigns since the facility was taken over by the University of Alaska Fairbanks (UAF) Geophysical Institute 18 months ago. Among the investigators is UAF Researcher Chris Fallen, KL3WX, who will be working under a National Science Foundation grant, “RAPID: Spatiotemporal Evolution of Radio-Induced Aurora.” Fallen says the HAARP transmissions will take place within the facility’s transmitter tuning range of 2.7 to 10 MHz and should be audible outside of Alaska and may even produce visible effects within the state.

Fallen's experiments will be carried out February 19-22.
“This time my experiments will largely focus on artificial radio-induced airglow that potentially can be photographed from nearly anywhere in Alaska — weather permitting,” Fallen told ARRL. “I plan to start and stop each experiment block with an audio Luxembourg-style broadcast — transmitting two amplitude-modulated carrier waves at different frequencies separated by about 1 MHz, with the resulting skywave signal being a mix of both frequencies.”

Fallen said that he has prior success reproducing the “Luxembourg effect” using two DTMF tones. “But this time, I have a short simple musical composition recorded by a local musician,” he said. “It was composed specifically to take advantage of the Luxembourg effect.”

According to UAF, Fallen, an assistant research professor in space physics, will create an “artificial aurora” that can be photographed with a sensitive camera within Alaska. The phenomenon has been created in the past above HAARP during certain types of transmissions.


Just which HF frequencies Fallen will use won’t be determined until shortly before he begins his research. “The specific frequency chosen during a particular experiment depends on the experiment’s objectives, FCC regulations, and ionospheric conditions at the time,” Fallen explained. He will use ionosonde data to guide frequency selection.

In an explanatory blog, Fallen explains that HAARP scientists use the ionosonde to estimate two important parameters: (1) the amount of low-level ionosphere D-region HF radio absorption that frequently occurs due to natural, but not well understood, processes that prevent HAARP radio wave energy from reaching the higher ionosphere E and F regions; and, (2) the ionosphere vertical “critical frequency” [sometimes referred to as foF2], above which any radio transmissions pass through the ionosphere into space rather than being reflected or absorbed.”


Fallen said experiment times and frequencies for his airglow and Luxembourg experiments will be updated on his blog and on his Twitter account linked in the blog. He encourages radio amateurs and SWLs to record the events they hear and post reports to social media or e-mail him.

Built and operated by the US Air Force until August 2015, HAARP includes a 40-acre grid of antennas and a very high-power array of HF transmitters to conduct ionospheric research. Scientists later this month will use HAARP to conduct other experiments that will include a study of atmospheric effects on satellite-to-ground communications and over-the-horizon radar experiments.

About HF radio transmissions from HAARP

HAARP is essentially a large powerful radio transmitter, similar in some respects to commercial large radio stations and radar installations. Unlike a commercial radio station, where radio (electromagnetic) wave energy is usually radiated in all directions to reach the largest possible audience, most of the HAARP radio wave energy is radiated in a relatively narrow beam, steerable by approximately 30 degrees off the vertical direction. Another unique feature of HAARP is that it can be tuned to transmit at any legally allowed radio frequency between approximately 2.7 and 10 MHz, or even two frequencies simultaneously. Radio waves in this HF band can often propagate large distances, sometimes completely around the Earth, by successively reflecting off the ionosphere, the Earth surface, and the oceans. (Radio waves with higher frequencies usually do not reflect from the ionosphere and simply pass through to deep space.)


Example audio recordings of HAARP radio broadcasts

There are several examples of HAARP broadcasts available online. Some of these examples were recorded intentionally due to prior announcement of HAARP activities, and some were recorded by happenstance by hobbyists who monitor the radio spectrum. If you know of other online examples of recorded HAARP transmissions please share them with me through the contact link at the top of this page so I can add them to the list below.

Moon bounce (HAARP was "aimed" at the moon to duplicate a favorite ham radio communication mode)

Luxembourg effect (HAARP transmitted two audio tracks at different radio frequencies simultaneously to duplicate the Luxembourg effect.

See the hissingchorusofdawn Soundcloud links from the linked NPR All Things Considered article.)

HAARP Oddities at 2.75 MHz Recording from the Mojave Desert of a HAARP transmission with a ULF amplitude modulation

HAARP Oddities at 5.8 MHz Recording of a HAARP transmission with an linear ramp amplitude modulation


73 - Petr, OK1RP
.../-.-

Thursday, January 26, 2017

Putting the K2 on 60m using K60XV module


Putting the K2 on 60m band using K60XV module


The K60XV adds 60-meter ham-band coverage to the K2 and K2/100 transceivers. In addition, it provides a low-level (0 dBm) split path interface for use with transverters such as the Elecraft XV Series.

60 Meters
Revision 2.04 K2 firmware allows the operator to quickly hop among the five fixed channels, as well as do channel-based scanning. The KPA100 option can be also used on 60 meters, but units shipped prior to March, 2004 will require modification (see page 2 of assembly manual).



Complete manual is here.

Specifications

60-meter coverage Approx. 5.0 to 5.5 MHz; see text for permitted transmit frequencies
Transverter T/R control PIN diode switching
Transverter output Low-level, approx. 0.1-1.0 mW (-10 to 0 dBm); linearized RF/ALC detector
Current drain Typically 1 to 2 mA in receive mode, 2 to 15 mA transmit
PCB size 2.0 x 2.6" (5.1 x 6.6 cm)


Firmware Requirements
K2: Revision 2.04P or later main microcontroller firmware is required (U6, Control board), and revision 1.09 or later I/O Controller firmware (U1, RF board). Serial number 4060 and higher K2s already have these revisions. To check the revision, hold any switch while turning the K2 on. Two numbers will be displayed: your main microcontroller revision on the left (e.g. 2 . 0 3 D ), and the IOC revision (e.g. 1 . 0 7 ).
If either is not current, you must obtain an update from Elecraft (order #FWK2MCIO). This new firmware is included free of charge with the purchase of the K60XV kit on request.

Source: http://www.elecraft.com

73 - Petr, OK1RP
.../-.-









Putting the K2 on 60m w/o K60XV...

Putting the K2 on 60m band w/o K60XV
 
An Elecraft re-post information on how to put the K2 on 60 meters for those who are anxious to try out the band without the K60XV optional module. K2 firmware does not at present include 60 m in the band map, so the modification works by "sharing" 40-meter components.

Note: This modification is recommended for experimentation only. However, a few hams in the UK have made these changes successfully, and Elecraft own initial tests show that performance is the same as on the other bands.

1. The 40 meter band-pass filter must be resonated on 60 meters:
Install a DPDT switch on the rear panel, close to the 40-m band-pass filter. The two switch commons should be wired to either side of C6, the top coupling cap in this filter. In the 60 m switch position, a 4.7 pF capacitor should be placed in parallel with C6. From either side of this capacitor to ground, you'll need a 50 pF trimmer and a 47 pF fixed cap, in parallel. The filter will be peaked later.

2. Memories can be set up for easy 60m or 40m access:
Turn on the K2 and switch to 40 meters. Select the 1-kHz-per-step VFO tuning rate and tune the VFO down from 40 m to the center of the 60 meter band (~5.3 MHz). Hit A=B to set both VFOs to this frequency, then STORE the setup in a frequency memory (I used #5 since this is 5 MHz). Then tune back up to 40 meters, hit A=B, and STORE this in another memory (#7 makes sense: 7 MHz). Now you can jump to either 60 or 40 meters using the RCL button. Of course you could assign up to 5 memories for use on the new channelized 60-meter assignments.



3. The VCO requires additional capacitance:
Use RCL #5 to get back to 60 meters. The PLL will be out of lock because the 40-meter VCO capacitance is too small to allow the VCO to tune down to 5.3 + 4.9 = 10.2 MHz. To get the PLL to lock, you'll have to parallel some 30-70 pF of extra capacitance across C71. Connect a voltmeter to R30, and find a value of C that results in a VCO voltage of 1.5-7.5 V over the desired 60 m segment. Then install a tiny SPST switch on the board which, when thrown to the 60 m position, puts this cap into the circuit. Use very short leads, and cut an access hole in the bottom cover. (Note: the K60XV will be supplied with two MV209 varactor diodes, D19 and D20, that will work in combination with the K2's new "D19" menu entry to change the VCO tuning range so that it covers both 40 and 60 meters with new VCO relay combinations. You don't need new K2 firmware to use the fixed capacitance method described here. But if you have it, leave "D19" set to "N".)

4. With both the VCO and BPF switches in the 60 m position, and a 60-m memory recalled, align the BPF trimmers on 60 meters in RX or TX mode.

5. The K2's original 40-m low-pass filter and push-pull PA does a decent job of suppressing the 2nd harmonic on 60 meters, but if you want some extra margin, use the new 40m/60m elliptic low-pass filter components shown in the Revision D K2 manual. These components are already present in K2s s/n 3000 and up.

You're now ready to use the K2 barefoot on 60 meters (up to 15 W). Remember to use upper sideband *only* as we haven't yet convinced the FCC to let us use CW. 

The KAT2 and KAT100 automatic antenna tuners will both work on this band, so you can use a 40 or 80-meter antenna or a random wire.

DO NOT use the KPA100 on 60 meters unless you have the means to check 2nd harmonic suppression. Since the KPA100 uses a 40/30 meter low-pass filter, the 2nd harmonic attenuation on 60 meters would be determined solely by the balance of the PA strip, which may or may not meet FCC specs. A future modification to the KPA100 will allow use on 60 meters. (Also note the carefully-defined 50-watt power limit on this band. See
http://www.arrl.org  for details.)

Source: http://www.elecraft.com/


73 - Petr, OK1RP
.../-.-

Kenwood TS-590 (ver.E) TX modification for 5MHz by Roar, LA4AMA

Kenwood TS-590 TX modification

The E version (Europe) has no TX on 5 MHz, but the K version (USA has 5 MHz TX between 5.250 MHz and 5.450 MHz. According to the service manual (page 120) the difference between E and K version is a jumper (R968) which is installed in E version but missing in the K version.

There are 2 possible TX extensions on the E version, either full TX (1.705 – 30 MHz) or just open up 5 MHz (cut the R968 jumper and make it into a K version).


Complete modification guide is here

Thanks to Roar, LA4AMA for sharing this mod.


73 - Petr, OK1RP
.../-.-

Monday, January 23, 2017

Antennas for 60m - Inspiration by Iulian, VA3IUL

Hello,

these antennas inspirations are not appointed to just 60m but it can help you when you are planning your antenna for 60m band or you are thinking about an improvement...

































References:
 
Antenna Toolkit - J. Carr
Practical Antenna Handbook - J. Carr
More Antenna Classics - C. Hutchinson
Amateur Radio Techniques - P. Hawker
The Radio Handbook - W. Orr (editor), 15th edition
The Radio Antenna Handbook - Engineering Staff of "Radio"
Jones Antenna Handbook - Frank C. Jones
SM0DTK - http://www.sm0dtk.se/antennas.htm
ARRL Antenna Handbook 1990-2007
ARRL Handbook 1937-2009
ARRL Antenna Compendium
73 Magazine 1970-2002
Funkamateur Magazine 1990-2011
RSGB Handbook - 2007 - 2010
QST Magazine - 1980 - 2010
Ham Radio Magazine - 1969 - 1990
Radio-Electronics Magazine - 1986 - 1990
 

Thanks to Iulian, VA3IUL for ideas. Maybe it will help and inspire others to install better antennas for 60m band too...


73 - Petr, OK1RP
.../-.-

IARU-R3 Band plan for 60m - update by NZART

Hello,

short info arrived from NZART Administration Officer to my queries...


  • What is the status of the IARU Region 3 band plan? (As far as I am aware, the only published 5 MHz plan is a draft put together by IARU Region 1.)  
  • What is the status of the 5 MHz band in New Zealand?  (No allocation as yet but discussions are ongoing with the regulator and current licensees)


  • So in fact no additional information or news are available yet.
    The current band plans are available as I posted already here:



    73 - Petr, OK1RP
    .../-.-

    Tuesday, January 17, 2017

    Last aid antenna for 60m - helical whip

    Hello all,

    are you one of those wretches with absolutely no space (mean zero space) for antenna and you would like to try QSO on 60m band?

    Well except the magnetic loops you can try also this crazy helical whip...


    Please forget it if you have space for at least 10m piece of wire outside to be used as random wire antenna (horizontal, zig-zag, sloped or even vertical) and grounding point or counterpoise close to your ham-shack...


    If there is no way for anything better and for some reasons you can not use the small loops then your last wretch's aid is this helical stick.

    http://www.nevadaradio.co.uk/amateur-radio/antennas/mobile-antennas/am-pro-60


    • 5 MHz single band whip
    • Power rated : 250w
    • Fitting : standard 3/8" thread
    • Length : 245cm (max)
    • Bandwidth : 50kHz
    • Slimline design


    Sometime something is better than nothing...


    73 - Petr, OK1RP
    .../-.-