Tuesday, 18 February 2020

Ham Radio-No repeaters?


Ham Radio-No repeaters?


Ham Radio-No repeaters? D-Star is one of the modern digital communications modes which are gaining pace in the Ham Radio world. Call routing GPS location and data transfer are three benefits to the new radio ham with an interest in digital communication. Ham radio is essentially about communicating with people and how this is achieved is a matter of choice for today's Ham community.


What is D-star?

D-star IC-7100

D-star IC-7100



When H.F. conditions are poor and Maximum Useable Frequency measurements do not allow traditional Radio signals to be propagated around the world, D-star or one of the other popular digital voice modes can make a significant difference to the keen radio ham who likes to converse, or as we say in the Ham Radio World, engage in a Q.S.O., which means to be in contact with.

How do you operate on D-Star when no local repeaters are within your vicinity. The answer to this problem is to secure a Digital Voice Access Point, or D.V.A.P.; this small device simply plugs into the USB port on your computer or laptop and allows any suitable D-star transceiver to connect to the International digital network.


There is now a more comprehensive digital access point, the open spot2, see above.

The D.V.A.P. is available on two meters or seventy centimeters and is essentially a low powered transceiver on either of these bands. The output of the device is around 10 milliwatts which are strong enough to allow connection from a hand-held transceiver to connect to and receive the digital signal. A USB lead is supplied together with instructions on how to download the software from the manufacturers website.

On one end of the D.V.A.P. an s.m.a. socket allows connection to a suitable Aerial, a stubby aerial is supplied but I have found connecting the device to an outside vertical improves not only the range it also allows for a more stable connection. 

The D.V.A.P. was not designed to be plugged into an amplifier and looking at the spectrum of my model which is the two-meter version I have discovered that the low powered signal is not as clean as other low powered devices, however, it works very well and achieves its purpose which is to allow reflector operation and International communication where no D-Star repeater exists.

D-star has its place in today's Ham radio community; it is an effective communication system between continents and will probably improve as time moves forward. 

I speak with several mobile stations in the U.S.A. On a regular basis and find the mode convenient to use while operating pedestrian mobile with my hand-held I-com ID-51-E transceiver. For those of you who no longer can erect aerials outside due to physical conditions, or due to problems of old age, 
D-star and the D.V.A.P. gives you the opportunity to engage in Ham Radio communication which you may have enjoyed for a number of years using conventional multi-hop propagation via High-Frequency Ham bands.

Ham Radio-No repeaters?






Ham Radio-D-STAR


Ham Radio-D-STAR


Ham Radio-D-STAR. There are many different interests within the umbrella name of Ham Radio. People communicate with other like-minded people around the World using the Internal Short Wave bands. 

D-STAR UK REPEATER LIST

D-star IC-7100

D-star IC-7100



Ham Radio Operators equipment include H.F., (High Frequency), transceivers covering several of the Ham Band allocations and many use Yagi aerials with three, four and sometimes six elements, to not only transmit their power out to the receiving station, but also to receive weak signals from lesser equipped ham radio Operators using simple aerial systems such as dipoles or vertical radiators. 


These aerial elements can be thirty-three feet long when covering the twenty meter Ham Band, if the elements are widely spaced between each other at say point two of a wavelength, the distance between the elements is four point two meters, a very large aerial indeed.

Many Radio Hams who I have spoken to around the World have sixty feet high towers with multi element aerial as described above. You need a lot of space for such an aerial, and planning permission to go along with it.

D-Star and DMR are Ham Radio modes which are gaining in popularity, because the problems associated with having a large aerial do not exist, signals on D-star and DMR do not rely on the ionosphere to propagate signal around the World, they use laser light and data packets used to facilitate the International World wide web.

Many elderly radio Hams who have moved from their long term family homes, into small apartments, where outside aerials are not allowed, are finding that their interest in communication can still continue, using D-star or DMR modes of communication. The digital mode also has a great advantage over traditional propagation. You need propagation to be working in your favor when using High-Frequency bands. If there is no propagation on a particular Ham Band, you simply do not hear any signals. D-star and DMR modes rely on the efficiency of the Internet, offering Radio Hams Worldwide communication without the need for natural reflection and refraction of the transmitted signal via the Earth's Ionosphere.

Handheld transceivers capable of Digital transmission are now freely available from many of the Ham Radio retailers. Their transmissions are converted from standard analog voice signals via voice encoders built into the handset, these transmissions are picked up via local repeaters that are connected with each other to form a Worldwide network, if you do not live beside a D-star or DMR repeater, you easily can turn your home-based computer into a repeater with inexpensive add-on technology, they do the same job as the nearby repeater does.



Ham Radio-D-STAR