14 November 2009

Ham apps with tones

There exist several apps with test tone generator functions. This FreqGen app is simple to use. Read here. I did find this app useful i.e. to start up a FM repeater with a 1750 Hz tone call. The modern FM rigs has this function in-built, but sometimes it is hard, without the manual, to remember how to do it and of course when using a radio without this function. In this video you can see and hear when I used this app to start the FM repeater SK0RDZ, some 60 km away from my home QTH, on 145.650 MHz with a 1750 Hz tone call. The microphone of an Yaesu FT-857D was held near the iPod Touch gen 3 loudspeaker.

Another app that I have found useful is the DTMF Pad for generating DTMF tone pairs. Normally you use a microphone with DTMF buttons i.e. to access FM repeaters all over the world via the EchoLink system. But if do not have such a microphone this app is very handy. In this video you can watch how I used this app to randomly access a repeater connected to the EchoLink system. I just held the transceiver´s microphone close to the loudspeaker of my iPod Touch gen 3. The repeater I used for this demonstration was SM0HGS/R (node 7485) on 145.725 MHz in Stockholm, Sweden and KD0IZY in New London, Iowa, USA was randomly accessed.

Spy radios

Yesterday I went, with my two small grandchildren, to the nearby library in Handen Center, Haninge. They have a nice reading corner for the small ones. They also have the Nordic amateur radio magazines. Of course, after parking the children, I went to the magazine department. And there was the September issue of NRRL´s magazine with its cover photo above, by Sindre Torp LA6OP, of a real spy radio station.This station, in custody of the Norwegian CIA, was used a long time by a Norwegian spy from 1948 to 1967. The radio was camouflaged to look like a US made station but it was built in the Soviet Union.

Is it possible to build an exact copy of a Paraset today asks Johnny, SM7UCZ himself on his web site. I have seen and touched his first replica of the WW II the secret agent Paraset radio. This time he is building an exact one! I can strongly recommend visiting his site.

Photo above by Johnny, SM7UCZ.

When building an exact replica you need a spotwelding machine. What do you do if you don´t have one? You do as Johnny, SM7UCZ does. Build your own! Have look here on his spotwelding project. The text is in Swedish, but that does not matter. I think you will understand how he did it by just looking at the photos.

Photo above by Johnny, SM7UCZ