# 5.8 Ghz cordless phone **URL:** \ **Category:** Factual Questions\ **Created:** [January 21, 2003, 5:27pm UTC](https://boards.straightdope.com/t/5-8-ghz-cordless-phone/150006 "2003-01-21T17:27:58Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![dauerbach](https://avatars.discourse-cdn.com/v4/letter/d/c2a13f/32.png) [@dauerbach](https://boards.straightdope.com/u/dauerbach)\ **Post date:** [January 21, 2003, 5:27pm UTC](https://boards.straightdope.com/t/5-8-ghz-cordless-phone/150006/1 "2003-01-21T17:27:58Z")
Do the new 5.8 Ghz cordless phones offer any significant advantages over the 900 Mhz or 2.4 Ghz models? ---
**Author:** ![robby](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/robby/32/11048_2.png) [@robby](https://boards.straightdope.com/u/robby)\ **Post date:** [January 21, 2003, 6:49pm UTC](https://boards.straightdope.com/t/5-8-ghz-cordless-phone/150006/2 "2003-01-21T18:49:58Z")
Of course! The 5.8 GHz phone has more than twice as many gigahertz as the 2.4 GHz, which has more than twice as many as the 900 MHz phone! Therefore it must be twice as fast, or have twice the range, or…something. Or so the manufacturers and the RadioShack drones would have you believe.:rolleyes: They do cost twice as much, though! ---
**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:** [January 21, 2003, 6:54pm UTC](https://boards.straightdope.com/t/5-8-ghz-cordless-phone/150006/3 "2003-01-21T18:54:48Z")
They are supposed to offer increased range and clarity, according to the packaging. However, with increasing frequency, electromagnetic radiation in the RF tends to be absorbed more easily by materials in bulding construction, so you probably lose quite a bit of range in many situations ---
**Author:** ![Epimetheus](https://avatars.discourse-cdn.com/v4/letter/e/c4cdca/32.png) [@Epimetheus](https://boards.straightdope.com/u/Epimetheus)\ **Post date:** [January 21, 2003, 7:00pm UTC](https://boards.straightdope.com/t/5-8-ghz-cordless-phone/150006/4 "2003-01-21T19:00:48Z")
I always thought that the higher the hertz, the better the quality but with lower range. How do the phones work that way- what exactly does the hertz rating work on these phones? ---
**Author:** ![Belrix](https://avatars.discourse-cdn.com/v4/letter/b/ed655f/32.png) [@Belrix](https://boards.straightdope.com/u/Belrix)\ **Post date:** [January 21, 2003, 7:04pm UTC](https://boards.straightdope.com/t/5-8-ghz-cordless-phone/150006/5 "2003-01-21T19:04:05Z")
> [@](#): > > \*Originally posted by Q.E.D. \* > \*\*However, with increasing frequency, electromagnetic radiation in the RF tends to be absorbed more easily by materials in bulding construction, so you probably lose quite a bit of range in many situations \*\* That doesn’t sound quite right - high-freq tends to penetrate better than low freq. Consider the ability to listen to AM radio in the center of a building as compared to FM with its higher frequency. ---
**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:** [January 21, 2003, 7:23pm UTC](https://boards.straightdope.com/t/5-8-ghz-cordless-phone/150006/6 "2003-01-21T19:23:21Z")
It depends largely on moisture-content, as well as other factors. Anyone who has satellite TV knows the microwave signal can be blocked by leaves or heavy clouds. These things offer no impediment whatsoever to FM-band broadcasts. And the Navy uses ELF–Extremely Low Frequency (a few hundred kilohertz) to talk to submarines under water, since higher bands won’t penetrate. Many building materials, such as wood, sheetrock, and plaster, are fairly good at holding moisture (even though they FEEL dry), which can strongly attenuate a high-frequency RF signal. ---
**Author:** ![robby](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/robby/32/11048_2.png) [@robby](https://boards.straightdope.com/u/robby)\ **Post date:** [January 21, 2003, 7:31pm UTC](https://boards.straightdope.com/t/5-8-ghz-cordless-phone/150006/7 "2003-01-21T19:31:12Z")
What **Q.E.D.** said. This lecture in PDF format discusses the different frequency bands and some of the factors affecting range. [http://www.winlab.rutgers.edu/~narayan/Course/Wless/Lectures02/lect1.pdf](http://www.winlab.rutgers.edu/~narayan/Course/Wless/Lectures02/lect1.pdf) ---
**Author:** ![dauerbach](https://avatars.discourse-cdn.com/v4/letter/d/c2a13f/32.png) [@dauerbach](https://boards.straightdope.com/u/dauerbach)\ **Post date:** [January 21, 2003, 8:49pm UTC](https://boards.straightdope.com/t/5-8-ghz-cordless-phone/150006/8 "2003-01-21T20:49:50Z")
Thanks alot. That’s pretty much what I figured from when I researched the then new 2.4 Ghz when they first came out. I thought maybe 5.8 did something magical. Clearly, it doesn’t.