Panasonic KX-TG5230M 5.8 GHz Expandable Cordless Phone

Rating:
Summary: Best Range of all 5.8 GHZ Expandables
Review: Save yourself the time and trouble - over the past month (August 2004) I have tried the latest models of just about every major brand that offers 5.8 ghz multi-handset cordless phones - Uniden, V-Tech, AT&T (made by V-Tech), Motorola, and Panasonic. Each of these phones is nice in its own way, but only the Panasonic had enough range to receive and send clearly from one end of the house to the other. Granted my house is a little large (3,600 square feet, all one one level), but the other brands maxed out about 2/3rds of the way through the house. I do have a WiFi network in the house, and had no interference issues from that with any of these brands. I do wish the Panasonic could expand to a total of more than just 4 handsets, but that is a minor issue. Those big honking twin antennae on the base unit seem to actually work.

Rating:
Summary: Great phone with wireless network compatability
Review: Summary: This review is for those trying to buy a cordless phone with a wireless network (802.11 b/g) in mind, not a feature review as this was my main purchasing consideration.
There is a lot of conflicting information on the web regarding compatibility between 2.4 GHz cordless phones & wireless network. Manufacturers seem not to publish specifications on exact frequency ranges & power output.
My trusty old Panasonic gigarange 2.4 GHz (FHSS) phone was great, clear reception & excellent range. However it completely killed my 802.11b wireless network. A replacement was necessary.
After much research there were a few alternatives: 900Mhz, 1.8GHz DECT (not US), 2.4GHz or 5.8Ghz.
In general obstacle penetration range decreases with increasing frequency. ie all things being equal a 900MHz phone will have superior range through obstacles to a 5.8Ghz phone. However this is not quite the complete story as this is for a given transmission power. Manufacturers, however have ways of increasing the power output. One of these techniques is DSS or Digital Spread Spectrum. My understanding is that the authorities allow greater output by DSS phones. DSS also increases security.
So logically a 900MHz DSS phone will have the best range (best penetrating ability, best power output & security). However where I live there are no 900MHz DSS phones on the market any more.
So, the alternatives were 2.4GHZ Uniden WDECT, Panasonic 2.4GHZ DSS or Uniden/panasonic 5.8Ghz models.
I tested both the 2.4GHz models & whilst both did not affect the wireless network, the wireless network causes poor reception / clicking / pops when downloading large files. The wireless network also decreased the range of the phones. As such I could not recommend either phone with a wireless network.
Therefore my only choice was a 5.8GHz model, and based on price the panasonic was a winner.
My empirical observation was that it performed as well as the old 2.4GHz panasonic. This is probably where the decreased penetrating ability is offset with an increase in power output utilizing DSS.
The phone itself is crystal clear using the handset (at both ends of the conversation). Range diminishes significantly after passing through 4 brick walls. This is probably a better guide than 'line of sight distance' which is likely to be 1 Km (0.6 statue mile) in the open.
Overall an excellent phone, however, it is very expensive compared to the 2.4Ghz range considering the features (single phone, no answering machine etc). However if wireless networks are your issue the manufacturers have you over the proverbial barrel. The reason I gave it four stars was because of this lack of value only.

Rating:
Summary: A good phone
Review: The Panasonic is a good phone. I tried Uniden and it didnt work, so I tried Panasonic. I actually thought this had an answering machine, but was wrong. Don't get it if you need an answering machine. A good phone, a little pricy, but it's worth it.