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</style></head><body style=""><div>If you want to do any kind of mesh or copper foil screening, I wonder if doing just a single wall will make enough of a shadow.</div>
<div>And if you do want to do more walls, it is quite a job. All of the edges and corners will need to be connected as well (granted 144Mhz isn't that short a wave).</div>
<div>Quite a bit of cash involved as well, copper is not cheap.</div>
<div>Our MRI machines are in RF shielded cages as well (to keep our 20odd kW of RF inside :-) ).</div>
<div> </div>
<div>Can't he put the antenna higher?</div>
<div> </div>
<div>I'd perhaps look into proper RF shielding for the studio and chokes for the affected equipment in the rest of the house?</div>
<div> </div>
<div>Regards,</div>
<div> </div>
<div>Jarno.</div>
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<div> </div>
<div><br>> Op 28 november 2016 om 17:14 schreef Oakley Sound <oakleylist@btinternet.com>:<br>> <br>> <br>> Hi all,<br>> <br>> My next door neighbour, a keen radio ham, has erected a new 144MHz <br>> directional beam antenna. Unfortunately, for both of us, when it's <br>> pointing towards my house and transmitting, it interferes with my audio <br>> set-up in both my living room and my little music area. I get on very <br>> well with my neighbour and we've briefly worked together on this so we <br>> know what particular combination of output power, frequency and antenna <br>> choice causes the problem. This antenna mast is around 5m away from the <br>> wall where my audio gear is situated. When he uses his other non <br>> directional antennas there is no problem.<br>> <br>> Anything more than 20W and the RF signal has an affect. Generally, with <br>> my more modern gear it is not a problem, but my vintage gear (eg. my <br>> hi-fi and older synths) are badly affected. More annoyingly, it's also <br>> the modular and my ten year old Event active monitors.<br>> <br>> When transmission is ongoing I hear what seems to be a loud buzz at <br>> 100Hz and harmonics. It's as if the mains is being gated into the audio <br>> pathway during transmission. The higher the RF output power the louder <br>> the buzz. The Event monitors pick up the noise even with the audio <br>> cables unplugged and the mains additionally filtered. Bizarrely it also <br>> makes the modular and my old SY-1 go out tune but I can't detect any <br>> drop in power supply voltage so I think it's directly affecting the VCO <br>> circuitry.<br>> <br>> I think I may have solved it with ferrites on the loudspeaker cables on <br>> the hi-fi but the music area is still a problem.<br>> <br>> At the other end of my house I haven't got an issue but moving all my <br>> gear there isn't really practical - although I'm thinking about it.<br>> <br>> Any ideas? Would some sort of earthed wire mesh fitted to the wall <br>> directly between him and me create a suitable RF shadow?<br>> <br>> Tony<br>> <br>> www.oakleysound.com<br>> <br>> _______________________________________________<br>> Synth-diy mailing list<br>> Synth-diy@synth-diy.org<br>> http://synth-diy.org/mailman/listinfo/synth-diy</div></body></html>