ARI Udine OdV (IQ3UD): Your Technical Hub for Amateur Radio

Udine, Italy – The A.R.I. (Associazione Radioamatori Italiani) Sezione di Udine OdV, identified by its call sign IQ3UD, is a vibrant local chapter for amateur radio enthusiasts with a strong focus on technical knowledge and experimentation.

The section is located at VIA A. DIAZ 58, 33100 UDINE UD. For inquiries, you can contact President IV3GDE Minin Alessio. Meetings are held every Wednesday from 9:00 PM to 11:00 PM.

For more technical resources and information, visit their website: www.ariudine.it.

Technical Resources and Articles

The ARI Udine website provides valuable technical information, including translations of several articles:

• "Yagi Stacking beam on 50 MHz" by G3wos
• "EME propagation on 50 MHz, 144MHz e 432MHz" by GM3sek
• "BAND-PASS FILTER for VHF"
• "F194/U Bandpass Filter"
• "AMPLIFICATORE HENRY RADIO 2002-A & 2006-A - 2m. / 6m."

Yagi Antenna Coupling Methods

The section also shares practical insights into coupling Yagi antennas, outlining three common methods:

1. Using two pieces of 75 Ohm coaxial cable: This is the most economical method. The cables should be well-stripped and preferably of good quality to avoid a 3dB gain loss. The cable lengths should be odd multiples of a quarter-wavelength multiplied by the cable's velocity factor.
2. Using a 1/4 wavelength coaxial coupler: This is the simplest system. It uses 50 Ohm cables that are multiples of half-wavelengths.
3. Using a hybrid ring: This method offers a significant advantage: if one antenna breaks, the transmitter will still see a 50 Ohm load.

ARI Udine actively supports its members in understanding and implementing advanced radio techniques, fostering a community of technical learning and practical application.