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<DIV><FONT size=2>I just got this info about some testing on cell
phones.</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>Don</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV>
<DIV><FONT face=Arial>Hi Don,</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>I am following the NSRCA mailing list but am not a member.
Because of this I cannot mail on the list without censors reading it first, so I
decided to reply to you directly.</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>The use of cell phones with R/C equipment has been
discussed on the the list in August last year, I do not remember the consensus.
</FONT></DIV>
<DIV><FONT face=Arial>A couple of years ago I found a test report on the
Internet, in German. That page does not exist anymore but the story goes like
this:</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>An R/C helicopter crashed when the pilots cell phone rang.
The phone was on the belt. The insurance company and DMFV (Deutscher
Modellflieger Verband, German "AMA") got interested. A radio specialist (MSc in
RF) and an R/C pilot himself carried out the tests.</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>Results:</FONT></DIV>
<DIV><FONT face=Arial>- Robbe Futaba FC-28 (exactly the same technology as
Futaba 9Z) with synthesized RF module lost control when a cell phone was very
close to it, less than 40 cm distance. It turned out that it was not
interference, but the transmitter was was not able to hold the right frequency,
IOW it was sending with a false frequency. </FONT></DIV>
<DIV><FONT face=Arial>- Same transmitter with a non-synthesized RF module
was totally unaffected by a cell phone</FONT></DIV>
<DIV><FONT face=Arial>- Several other JR and Futaba (probably also
Multiplex) transmitters were tested. No effect at all !</FONT></DIV>
<DIV><FONT face=Arial>- Various brands and types of receivers and servos
were also tested. No effect at all !</FONT></DIV>
<DIV><FONT face=Arial>- Receivers were tested at the flying
distance</FONT></DIV>
<DIV><FONT face=Arial>- In these tests the R/C equipment was 35 MHz and
cell phones 900 and 1800 MHz. In the USA teh frequencies are different but basic
rules against interference applie the same.</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>So the Futaba synth module may be affected by
cell phone. It is also important to avoid close proximity of cell phone at
the pits, because the transmitting frequency is possibly altered. You may shoot
someone else down ! </FONT></DIV>
<DIV><FONT face=Arial>The sensitivity of other brands i do not know, but why
take a chance.</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>On the other hand what is the benefit of having a phone
close to you while flying, since you cannot answer it anyway. If you have a
hands free, you still have to concentrate on flying.</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>Best regards,</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>Iiro Nikkila</FONT></DIV>
<DIV><FONT face=Arial>Finland</FONT></DIV>
<DIV><FONT face=Arial>F3A, Futaba 9ZAP with TK-FSS module</FONT></DIV>
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