Wave Fronts

Home communication

A first installment about my home communication setup

My home equipment related to communication looks mostly like the diagram below. It's "mostly" because since making this graphic there have been a number of changes.

Everything but the FM transmitters and Linksys storage box (NSLU2) has been running for some time, with the latter two items still "in development." The two adventures so far have involved trying to use the Motorola WE800G in pairs bridges and tuning the FM transmitters.

The WE800G is similar to the Linksys WET11 and Dlink DWL-810 (the three specific models I've had direct experience with). I'm convinced he majority of users put a bridge like this in place as a means of connecting a wired ethernet port to a wireless network. That is, the bridge connects a wired port to a wireless access point or bridge. I'm pretty sure a miniscule minority of users put a pair of bridges in place as "wireless CAT5 cable" to connect two networks or network segments togetgher. I think this is true because both the WET11 and WE800G seem to be extremely unreliable for the latter application. I'd been warned about the WET11 and didn't waste much time on them, but the much more recent WE800G design and an initial successful two day trial led me to believe they would be solid. I was wrong and after buying a third to try to eliminate failed hardware as a factor and after countless experiments I gave up on them and redesigned my network so I didn't need a pair of bridges. Although they don't show on my network map I have a pair of the DWL-810 bridges but I haven't been tempted to see if they are reliable in 'wireless CAT5" mode. I should mention these three bridges are all cheap to very cheap and I never found a moderately priced alternative (say in the $250 range) that offered prospects for rock solid performance. The prices seemed to go from $50-150 to $500 and up. Taking hassle factor into account I probably should have payed the bigger bucks.

The FM transmitters (a British Veronica model) are wonderful except they weren't designed with current receivers in mind. It's straight forward to tune them to an unused portion of the band, but it's beyond tedious to tune them precisely enough that a receiver with digital tuning receives their signal properly. Tuning is by a compression type variable capacitor that is beyond touchy. So the two old GE radios in the house and the clock radio work fine, but the home stereo and walkman type radios are useless. Even supposing I can make the tuning tool I need, the frequency stability is questionable. Veronica is absolutely straight up about this, saying 25khz is what you get. So I have to tweak analog tuned receivers from time to time to get them back in line with the transmit frequency. If I'm lucky and can get the tuning just right after allowing temperature to stabilize it might stay within the capture range of a receiver for the long term. But to go along with an exaggerated T-handle tuning device I may need something akin to a crystal oven for the transmitter to try to control the temperature and make retuning less frequent. If this sounds like a hassle you're appreciating the situation.

The other factor is that I want coverage around the house. The Veronica claim is 100 meters range and I've confirmed half of that range with transmitter and receiver on the same level, but most of the house gear is in the basement while most of the living is on the main floor. Now in most parts of the world it would be a trivial issue to just run a shielded cable from the sound source up to the transmitter. However here in the southeast USA lightning storms are a chronic issue and the property here is on relatively high ground. So I have to weigh the risk of blowing up the critical bits and pieces of house equipment for the sake of getting the FM antenna up to a proper position. Actually, increasing the chances of preserving equipment with lightning storms is a whole other story.

Posted at 06:54PM Oct 08, 2005 by microwaves in Home Nets  |  Comments[0]