# Why does the human body act as a radio/TV antenna? **URL:** \ **Category:** Factual Questions\ **Created:** [February 11, 2004, 11:44pm UTC](https://boards.straightdope.com/t/why-does-the-human-body-act-as-a-radio-tv-antenna/228748 "2004-02-11T23:44:37Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![BrainGlutton](https://avatars.discourse-cdn.com/v4/letter/b/82dd89/32.png) [@BrainGlutton](https://boards.straightdope.com/u/BrainGlutton)\ **Post date:** [February 11, 2004, 11:44pm UTC](https://boards.straightdope.com/t/why-does-the-human-body-act-as-a-radio-tv-antenna/228748/1 "2004-02-11T23:44:37Z")
I’ve often noticed, when trying to adjust a radio or TV antenna for better reception, that reception improves markedly while I am holding or touching the antenna – and then, maddeningly, goes back to static or snow the moment I let got. Why is this? What is there about the non-metallic human body that should enhance radio or TV reception? And how, if at all, can we exploit this principle to improve reception without holding on to the antenna every second? ---
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [February 12, 2004, 12:11am UTC](https://boards.straightdope.com/t/why-does-the-human-body-act-as-a-radio-tv-antenna/228748/2 "2004-02-12T00:11:40Z")
The human body does conduct electricity (think salt water), and so it can be a pretty good antenna. Metal is better, and wood or plastic is worse (or no good at all). Adding a bigger antenna out of any conduction material will make your TV reception better. ---
**Author:** ![kezami](https://avatars.discourse-cdn.com/v4/letter/k/eb8c5e/32.png) [@kezami](https://boards.straightdope.com/u/kezami)\ **Post date:** [February 12, 2004, 12:27am UTC](https://boards.straightdope.com/t/why-does-the-human-body-act-as-a-radio-tv-antenna/228748/3 "2004-02-12T00:27:22Z")
I use my body as an antenna when I start my vehicle remotely. What I do is hold the transmitter under my chin when I depress the button - it increases the range of operation considerably. ---
**Author:** ![GorillaMan](https://avatars.discourse-cdn.com/v4/letter/g/50afbb/32.png) [@GorillaMan](https://boards.straightdope.com/u/GorillaMan)\ **Post date:** [February 12, 2004, 12:33am UTC](https://boards.straightdope.com/t/why-does-the-human-body-act-as-a-radio-tv-antenna/228748/4 "2004-02-12T00:33:44Z")
> [@John Mace](#): > > Adding a bigger antenna out of any conduction material will make your TV reception better. Not true. The optimum size for an antenna is the typical wavelength it is expected to receive - the the case of TV aerials, about 2ft. ---
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [February 12, 2004, 1:52am UTC](https://boards.straightdope.com/t/why-does-the-human-body-act-as-a-radio-tv-antenna/228748/5 "2004-02-12T01:52:38Z")
Good point, but isn’t it actually any integral multiple of the wavelength? ---
**Author:** ![Ms2001](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ms2001/32/18463_2.png) [@Ms2001](https://boards.straightdope.com/u/Ms2001)\ **Post date:** [February 12, 2004, 2:16am UTC](https://boards.straightdope.com/t/why-does-the-human-body-act-as-a-radio-tv-antenna/228748/6 "2004-02-12T02:16:40Z")
I’ve noticed the same thing, but even when I’m not touching the antenna. I used to have an FM transmitter in my car, and the signal would suddenly get better if I put my hand anywhere near the wire. ---
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [February 12, 2004, 2:24am UTC](https://boards.straightdope.com/t/why-does-the-human-body-act-as-a-radio-tv-antenna/228748/7 "2004-02-12T02:24:59Z")
> [@John Mace](#): > > Good point, but isn’t it actually any integral multiple of the wavelength? Or even an **integer** multiple. 🙂 Mr2001: Air can also conduct electricity, which is why capacitors don’t use air as the dielectric. ---
**Author:** ![ftg](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ftg/32/2801_2.png) [@ftg](https://boards.straightdope.com/u/ftg)\ **Post date:** [February 12, 2004, 2:40am UTC](https://boards.straightdope.com/t/why-does-the-human-body-act-as-a-radio-tv-antenna/228748/8 "2004-02-12T02:40:49Z")
The closer to an integral (check your dictionaries) multiple or _divisor_ of the wavelength is best. So 2 and 1/2 wavelength are next best. The difference between 1 and 1/2 wavelength is small enough in most cases that having the shorter antenna makes people happier. But the farther away from 1, the worse it is. (Well, there’s a lot of complications… look, over there, some to distract you!) So having a 4000\* wavelength antenna is no good. Also, once you get up to really massive antennas, other losses take over. So that “turn your whole house wiring into an antenna” gimmick is a complete scam. Also, I have dozens of capacitors in my house that _use air_! They are called tuning capacitors. Okay, so I’m a bit old timey, but if you have an analog dial radio, that includes you too. Air is considered an insulator for all practical purposes. ---
**Author:** ![Trigonal\_Planar](https://avatars.discourse-cdn.com/v4/letter/t/0ea827/32.png) [@Trigonal\_Planar](https://boards.straightdope.com/u/Trigonal_Planar)\ **Post date:** [February 12, 2004, 5:00am UTC](https://boards.straightdope.com/t/why-does-the-human-body-act-as-a-radio-tv-antenna/228748/9 "2004-02-12T05:00:15Z")
I always thought the improved reception had more to do with the body’s extra capacitance than any sort of antenna effect. ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [February 12, 2004, 5:07am UTC](https://boards.straightdope.com/t/why-does-the-human-body-act-as-a-radio-tv-antenna/228748/10 "2004-02-12T05:07:36Z")
> [@John Mace](#): > > Mr2001: Air can also conduct electricity, which is why capacitors don’t use air as the dielectric. Of course they do. Variable capacitors, often used as tuning components in old radio receivers, are air-dielectric capacitors. Air is actually a pretty good insulator at moderate voltages.