YU1AD                                                                         
MIRKO VOZNJAK
KATANICEVA 16
11000 BEOGRAD
SERBIA AND MONTE NEGRO

EMAIL: yu1ad@beotel.yu

I was born 77 years ago and operated as YU1AD, well known on SW and VHF. Worked around 285 countries on SW and on VHF had 51 country on 144MHz and 92 countries on 5OMHz.On 144 never used highspeed meteo- scatter, but tropo, sporadic E, aurora, and meteo scatter-random, never with prearranged skeds!!! Now I found that PSK is the best communications mode, saving tremendous amount of band space, and having miraculous DX possibilities, with low power. I think that all other modes will be soon buried, and only something better than PSK31, can survive.

Being an electronic engineer by profession, my constructional work was enormously big. I am also a good technical writer, having over 500 articles in local ham magazines, as well as 10 articles in U.K. magazines and two articles in CQ magazine.

Mirko,YU1AD

PROJECT 1: PC BOARDS FOR AF FILTER

For more info please contact: yu1ad@beotel.yu 

click for larger image

Mirko YU1 AD in his ham-shack, in which he is using exclusively home brew equipment, except SWR-meter and PSK interface...

 

 

 

 

 

 

 

ELECTRONIC DESIGNS BY YU1AD:

FIG 1: Please take a look my design of most modern tranceiver for SSB/CW only on 3.5 MHz. It uses ceramic filter as a very stable basis for VFX, covering easily 90kHz of the band. Receiver is direct conversion type, extremely sensitive, an by use Schottky mixer, very immune of  overloading by strong signal. It has two stage switchable AF BPF, with 120Hz selectivity. It has semi-duplex system, for very efficient operation. It is owned now, by very nice girl, named Ivana, she has call sign YT1RY,she won it on the quiz with the DX-thematic, on one of annual convention of YU amateurs.

 

 

 

 

FIG 2: Single band (14MHz) SSB/CW tranceiver, with output power of 20 Watts. Used barefooted for PSK-31,or as exciter for CW/SSB transistorized linear power amplifier, with 150 Watts output power. It uses HUFF-PUFF extremely stable VFO, which has a stability of few Hz, after 3 min. warm-UP. It is fully broad-banded, so beside of VFO, no tuning over entire band. Recently an excellent inter-face for PSK-31 has been added internaly, so it is really CW/SSB/ PSK-31 transceiver. As could be judged, both units are home made by YU1AD.

 

 

 

 

 

 

 Also please take a look the new design of AF SSB filter for Ham radio operators bellow: PC boards and schematics available for this unit (and many more) in kit form or assembled as well!

 

 

 

 

 

 

 

 PC BOARDS LAYOUT FOR FILTER DESIGN

 

      

Click for larger image                        Click for larger image

 

Email:  yu1ad@beotel.yu     

Broadcast equipment: www.rf-links.com 

Ham Radio modifications- the biggest site:

http://www.mods.dk/