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It's a fact that if you put a GSM cell phone near a desktop PC and call it, the phone will interfere with the audio card and cause that noise most of us have heard somewhere.

But is it the case with the stations? I've seen people shoot videos around the antennas, but it doesn't seem like they cause any noticeable audio noise. Is the signal different coming from the antennas?

user1306322
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    Related: http://electronics.stackexchange.com/questions/32830/why-does-gsm-cause-speakers-to-buzz – Ignacio Vazquez-Abrams Nov 12 '13 at 21:25
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    The signal is much stronger, but it's directional coming from the cell tower. It's also some distance away at the top of the tower. – pjc50 Nov 12 '13 at 23:07
  • Sure thing! A few years ago when 3G came here you could hear the base station constantly in some audio equipment. More when someone was using it. Not that loud but during silent parts between two songs on the radio for instance, you could hear it. – winny Sep 05 '16 at 07:53

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Not with any reasonably installed cell tower. If you were up on the pole next to the antennas, sure. The phone causes that sound because it transmits in relatively high powered bursts that get peak detected by parasitics in the audio hardware in the PC. Basically, the PC acts like an AM radio, albeit a horribly inefficient one. The phone needs to transmit with a lot of power so the tower can receive the signal. However, the tower's antenna is way up in the air and the transmit antennas use a 'pancake' beam pattern that's divided up into 3 (or possibly more) sectors. If you're right next to the tower, most of the signal is going over your head.

The bottom line is that the only reason your phone can cause that sort of interference is because of its physical proximity in combination with its transmit power. A cell tower antenna should be too far away to cause the same interference.

alex.forencich
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Cell phones do not to transmit with high power. The cell tower has two antennas: the vertical one for transmit omnidirectionally. The receive antenna are 3 rectangular directional antennas tipped slightly downward with approx 36db gain. At that frequency the noise is relative low and cellphone and celltower signal paths are usually line of sight. Cellphones are usually under a watt output. The interference is probably caused by the signals generated internally inside the phone or inside the PC. Since the mode used cellphones these days is digital mode and the PC and its sound card are digital devices. Interaction between devices is not unexpected just undesired. Better shielding is needed on the PC. I have a laptop with a sound card and I operate Amateur Radio equipment in close proximity to it and a much higher power than any cell phone. I operate in many modes both analog and digital with no interference whatsoever. That noise that was heard was the cellphone connecting to the tower.

Old_Fossil
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    Whats with the 3 down votes? – Old_Fossil Sep 07 '16 at 05:12
  • @ resident heretic .I think that downvotes should have reasons .This would encourage improvements .Maybe if the rep loss was reduced for the downvoter when the reason is good and increased when there is a bad reason and increased even further when there is no reason .Surely this would improve the quality of the site. – Autistic Feb 12 '17 at 03:21
  • @Austistic: Exactly. – Old_Fossil Feb 12 '17 at 19:18