A review of the EnGenius SN-920 by a user, 1/15/2001

EnGenius offers two outdoor antenna kits for the 920 phone. The only difference between the two is that one has a 10 meter cable (30 foot) and the other has a 20 meter cable (60 foot). I bought the 20 meter cable kit because that's the only one Office Depot had in stock:

The idea here is that you can screw off the stock antenna on the base--careful here, it has left hand threads--screw on a long cable, and connect that cable to an external antenna mounted on your house or a neighboring tree. I chose a tree for greater height.

Installing the outdoor antenna is expensive, difficult, and potentially dangerous. However, if you want the EnGenius SN-920 to function with its maximum range, this installation is absolutely necessary.

The first step is to assemble the antenna itself--a retro-sputnik looking device which looks as if it were put together from cell-phone antenna parts. This is pretty easy, just screw in seven antenna whips to a central hub, connect this to an aluminum support tube, and install the two clamps which allow you to secure the antenna assembly to the support mast. When complete, the antenna assembly looks something like this:

Let's start out with expensive. I noted above that the external antenna kit was $99 list price. That's not so bad, you say. But wait! The $99 kit is only the beginning! The kit contains the antenna assembly pictured above, and the cable. That's it. You next need an EnGenius Lightning Protector to protect the base unit. Then you need a pole or antenna mast on which to mount the antenna...oh heck, check out the table below for a complete rundown of items and their cost for my installation:

Discouraged? Did I mention expensive? Now, how about difficult and dangerous? The instructions (not copyrighted) for the outdoor antenna say, under Site Selection, "The higher the antenna is installed, the better the communication will be." That's the difficult and dangerous part. As high as possible!

This is difficult because it means that you need to acquire lots of other stuff beyond the stock antenna kit to get the antenna up where you want it safely. You'll need to assemble all this stuff. You can click on some of the items in the table above for details and pictures.

Because the highest point I could conceivably install the antenna was atop a 75 year old hemlock tree adjacent to my house, I hired an expert tree-climber named Tommy Lawson to install the antenna, wiring, and lightning protection system. It took us three hours--him in the tree, me ferrying up tools and parts by rope--to finish the installation. Here is the tree as it sits next to my house, with Tommy almost to the top:

Here is the outdoor antenna, mounted on a 20 foot mast pole, and finally secured to the hemlock tree:

As you can see from the above two pictures, the antenna is much higher than my house. As such, it poses a very real lightning hazard. This is why I chose to spend the extra effort and money to provide thorough lightning protection. Rather than relying on EnGenius' lightning protection kit alone, I grounded the antenna as if it were a lightning rod: that is, I ran a very large (#0) stranded copper conductor directly down the tree and terminated it in an eight-foot copper-clad grounding rod driven into the ground. The photo below shows the #0 copper conductor clamped to the bottom of the antenna mast prior to installation:

As I said, expensive, difficult, and dangerous!

EnGenius SN-920 User Review Home Page

1) Purchasing the EnGenius SN-920

2) Installation Without Outdoor Antenna

3) Testing the Range Without the Outdoor Antenna

4) Installation With the Outdoor Antenna

5) Testing the Range With the Outdoor Antenna

6) Technical Details and Miscellaneous Observations

7) WHY?

8) Conclusions about the EnGenius SN-920

9) Three years later...

10) Ten years later, the Project Ends

 

 

 

copyright Eric Geilker geilker5@aol.com