VHF-index of pa0nhc technical HAM pages.
20150407 / 20170623

Since 20150113 this site is located at: http://www.pa0nhc.nl  

EN = read English version article   NL = Nederlands



Nieuwe versie, makkelijk te bouwen ARDF 144 MHz peil ontvanger.
Optimale ontvanger eigenschappen.
Slechts 3 SMD componenten.
Alle overige componenten hebben draden of pennen voor makkelijke montage. 
Reeds gewikkelde spoelen.
Alles direct bestelbaar.
Goedkope, afschermende behuizing, zelf te maken van een stukje 50mm ALU pijp.
PCB maskers voor DIY printje zijn beschikbaar.
Dit nieuw ontworpen fabrieks print kan binnenkort bij mij besteld worden.

Ver 20160623-15. Size 102 x 43 mm2

This newly designed factory made PCB can soon be ordered from me.

New version, easy to build 144MHz ARDF radio direction finding receiver.
Optimal receiving properties.
Only 3 SMD components.
All other components are wired/pinned for easy assembling.
Coils are already wound.
All components readily orderable.
Cheap DIY screening housing : a piece of 50mm dia ALU pipe.
Downloadable DIY PCB masks available.

See also the 80m version



De oude techniek van de Rotterdamse repeaters PI3RTD en PI2RTD (ca. 1995-2005)


DIY VHF helix filters. 
Very selective, low insertion loss.
Very cheaply made from paint cans and copper wire.

One to four resonators.
Combinations with coax filters.
145MHz band pass and 160MHz reject.
EN 144 - 435 MHz wideband low-noise hi-IP preamp.
EN 3.5 - 435 MHz directional couplers on a small piece of PCB. Dependable and accurate.
EN 145MHz ARDF fox hunt antenna. VERY EFFECTIVE and light, proven design.

145MHz repeater duplex filter, made from PCB material and 22mm copper water pipe.
(GW4AKZ and Dirk Rijnenberg constructed one). Republished 20130529


Full theory on (145MHz) cavity filters(After a pencil paper from G8AMG)