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<H1>500 kHz Experiments </H1>
<P><FONT face=Verdana>From July 1908, 500 Kilocycle frequency commenced
operation as the recognised international CW marine calling and distress
frequency. In the UK and Ireland this service ceased in 1997 due to advances in
telecommunications technology. </FONT></P>
<P><FONT face=Verdana>However, in the past few years, special permits were
issued in Britain to radio amateurs for experimental purposes using frequencies
in the range <STRONG>501 to 504 kilocycles</STRONG>. </FONT></P>
<P><FONT face=Verdana>Ray, GI3PDN is the holder of one such license and a few
weeks ago he contacted Tony (EI5EM) to see if a crossband QSO could be arranged
with EI0MAR at the Martello Tower in Howth. </FONT></P>
<P><FONT face=Verdana><STRONG>A sked was arranged with EI0MAR operating on 3 550
kilocycles and Ray operating on 501.5 kilocycles. <BR>A successful two-way QSO
was completed with 559 reports both ways.</STRONG> </FONT></P>
<P><FONT face=Verdana><STRONG>Ray was using a home-brew transmitter running less
that one Watt into a 300 foot long inverted Vee antenna</STRONG>. No such
antenna was available at Howth where a 40-meter dipole tuned for 80 metres
was used for transmit and receive. </FONT></P>
<P><FONT face=Verdana>The rig used at EI0MAR was a Yaesu FT-747 running about 70
Watts. A second successful crossband QSO then took place with Finbar GI4PDE
(also EI0CF) in Derry but the report on 501.5 kilocycles was not as good at 339.
Tony, in arranging these QSOs approached it more in hope than in expectation and
was pleasantly surprised and very satisfied with this successful wireless
telegraphy experiment. A big thanks to Ray and Finbar for two very memorable
QSOs. </FONT></P>
<P><FONT face=Verdana>EI0MAR is located in the Vintage Radio Museum in
Howth and is QRV most Sundays. Further information is available on the web
or by email from “ei0mar at eircom dot net”. </FONT></P>
<P><FONT face=Verdana>A booklet about the museum and its history along with the
history of wireless is available for free download at </FONT><A
href="http://ei5em.110mb.com/museum.html" target=_blank><FONT
face=Verdana>ei5em.110mb.com/museum.html</FONT></A><FONT face=Verdana>.
</FONT></P>
<P><FONT face=Verdana>Fonte: </FONT><A href="http://www.irts.ie/"
target=_blank><FONT face=Verdana>IRTS</FONT></A><BR></P></BODY></HTML>