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Ten-Ten International Net #77458


My Ten-Ten International number is: #77458

I love 10 m band for his outstanding propagation, long distance communication with low power during the high solar activity.

Indeed, you don’t need a serious equipment and antennas to start working on 10 m band. Because it’s a top HF band the size of antenna usually small, so it wouldn’t be a problem to build an Yagi or Quad antenna. My first antenna for 10 m band was just a simple GP (ground plane), then I tried the vertical delta loop. Of course, the most advantage was with 3-4 elements Yagi. I opened the world of stations that I never seen before. Here in USA I continued work on my one of favorite band and eventually I became a Ten-Ten International member.

See you on the 10 m band. Active on SSB, CW, PSK31.

Ten-Ten International website is


K6VHF Soft

Very easy to use. Enter RF power, known antenna gain and approximate total cable losses. Click on “Calculate”. The ERP and EIRP results would be on right side. The difference is just reference to isotropic antenna or dipole. Also you’ll be able to convert dBd to dBi.

Download ERPC v.1.02


Bias Tee Calculator V 1.02

The Bias Tee calculator helps to calculate the values for a typical bias tee circuit (capacitance C and inductance L). You have to put input and output impedance, frequency and impedance ratio (usually value of 100). Right now the XL and XC calculates based on fixed impedance ratio but in next version they will be variable depend on different brands of capacitors and inductors.

Download BTC v.02


If you are designer and work with power amplifiers you will like this program.
There is
– Power Amplifier Calculator
– RC Time Constant Calculator
– Attenuator Calculator
– Watts to dBm and dBm to Watts Calculator
All test data can be save as TXT file.

Download EC v.1.06


A simple conversion calculator for everyday use US to Metric and Metric to US.

Download ECC v.1.0








For your convenient use – FSL Calculator.

Download FSL v.1.0




You may find it useful. It calculates the stacking distance V and H in 4 antenna stack array.

Download ASC v.1.05


Radio Mobile Software by Roger VE2DBE

Everyone who like VHF/UHF and contesting on this bands must know about this free tool. Yes it’s completely free to use but required a registration.
The website is here and a desktop version is here
Basically it’s tool that helps to predict and calculate a radio wave propagation on amateur bands.

Let’s read more about:

Radio Mobile Online is a radio wave propagation prediction tool dedicated to amateur radio.
It uses digital terrain information and a mathematical model to simulate radio transmissions between two fixed sites (radio link) or between a fixed site and a mobile (Radio coverage).
The digital terrain information comprises three databases: ground elevation, land cover, and population density. Those databases are located on the server and represent a total of 200 GigaBytes.
The mathematical model predicts the radio transmission performance based on the following entries:
• Transmitter power
• Transmitter line loss
• Transmitter antenna gain
• Transmitter antenna type (for coverage only)
• Transmitter antenna azimuth (for coverage only)
• Transmitter antenna tilt (for coverage only)
• Transmitter antenna height
• Transmitter latitude
• Transmitter longitude
• Transmitter ground elevation
• Elevation data records between the transmitter and the receiver sites (up to 2000 records)
• Land cover data records between the transmitter and the receiver sites (up to 2000 records)
• Receiver latitude (for link only)
• Receiver longitude (for link only)
• Receiver ground elevation (for link only)
• Receiver antenna gain
• Receiver antenna height
• Receiver line loss
• Receiver sensitivity (corresponds to the receiver threshold)
• Required reliability (The percentage of time where the signal must be above the threshold to consider a link to be liable).
• Color for a successful reception (for coverage only)
• Strong signal margin (for coverage only)
• Color for a successful reception with a strong signal (for coverage only)
• Transparency of the ground overlay (for coverage only)
The mathematical model is a mix of the ITM model, the two rays method, and the land cover path loss estimation.
The ITM model is a US government publication, public domain. The two rays method and land cover path loss estimation are based on my 40 years experience in radio propagation.
For a Radio Link study, the output of the mathematical model predicts success if the fade margin of the received signal is greater than zero.
For a Radio Coverage study, a colored plot over a topographical map is produced.

Frequencies allowed (MHz)

From To
10 30
50 54
70 70.5
144 148
222 225
420 450
902 928
1240 1300
2300 2310
3300 3500
5650 5725
5825 5925
10000 10500
24000 250000

For more detailed information please visit his website.

Let’s look at the examples for my QTH at DM04.

50 MHz Band - Yagi

50 MHz Band – Yagi

144 MHz Band - Yagi

144 MHz Band – Yagi

50 MHz Band - Omni, 6 dBi

50 MHz Band – Omni, 6 dBi

144 MHz Band - Omni, 6 dBi

144 MHz Band – Omni, 6 dBi

And this is an example of Point to Point (Radio Link) prediction.

K6VHF to W6BVB Radio Link

K6VHF to W6BVB Radio Link


Alex K6VHF

The Go-Bag for ARES or Portable Work

This is what I use for my ARES and emergency communication drills as well as for portable work (hiking or backpacking). As you can see it’s a simple backpack that you can find in many sport goods store (for example Big 5). I found that this backpack is perfectly meets my requirements. So what is inside?
It’s simple set-up that allows me to work on HF and have everything that I need. Of course it also have an other supplies that you will need for emergency situation or hiking.
Let’s look closely:
– IC-703+ (10 Watts with antenna tuner). The great transceiver for portable use. High reliability, ability to work with many antennas, easy to use.
– 12 V 10A battery. I use a regular 12 V, 10A battery which cost around $15. The better solution would be a Poly-MH batteries. Light weight and high current.
– solar panel + charger. Well this is very useful. Can be used for your battery or ether for your cellphone or other equipment.
– 5 m antenna pole (fishing rod). Found on eBay. Very cheap and fiberglass. The great mast for your portable antennas.
– Inverted V 14 MHz/28 MHz antenna (transformer). This is the ultra light and portable antenna-transformer. In my version is 2-band Inverted V antenna.
– extras (GPS, flashlight, rope and etc). This is really up to you.

The total weight of this set-up about 18 pounds which is not bad at all. I personally prefer have some snacks and small emergency(survival) kit, medicines and water.
Performance are good, not great but definitely enough to provide a communication in case of emergency and operate from any places with.
Time to set everything up and get ready is very short and it’s about less than 10 minutes.
Of course it’s not a perfect set-up and other people would prefer have something else but the main idea was – use everything that you can find in your home (garage), low cost and efficient work.
I have done this many times and when you live in California you never know when the earthquake or different disaster will strike this land.
You have to be prepared all the time and personal safety is always first.
I’m a CERT (Community Emergency Respond Team) member, Police Department & Fire Authorities Volunteer, member of ARES so my responsibilities are expended.
I hope you’ll enjoy it.

Alex K6VHF