A little while ago, I purchased a Jetstream JTD1 discone antenna off ebay for $34 (+shpping). The antenna is rated for 200 watts of transmit on 144 mhz, 220 mhz, 440 mhz, 900 mhz, and 1.2 ghz.
I finally got around to installing the antenna on the roof and took some pictures along the way.
Picture of the label on the bag with all of the specs:
There really aren't that many parts to assemble on one of these antennas:
The heart of the antenna is the hub. The bottom half that mounts to the mast is aluminum and the rest is stainless steel in between an insulator. The two allen screws on the side tighten the hub to the mast.
First mount the hub on a mast of some type to assemble the antenna. I have a small tripod and piece of mast for working with antennas on the ground:
First screw in the top 8 elements:
Now add the bottom elements and you're done with the assembly!
Here's the antenna mounted on 10 feet of mast on my roof:
As you can tell, the antenna is really simple to install. I already had the mast and coax run (a different antenna was in its place) so the whole procedure took at most 30-40 minutes, if that.
In addition to monitoring various bands, I'll use this antenna to transmit on 2 meters from time to time. I hooked up the analyzer at the transceiver to check the SWR and here's what I found:
At 144 Mhz:
At 146 Mhz the SWR spikes:
At 148 Mhz:
I've already been using the antenna to listen in on the local 440 repeater and have talked a bit on 2 meters. Remember, these antennas are unity gain and exhibit a fairly low angle of radiation.
Every ham needs a discone!
I finally got around to installing the antenna on the roof and took some pictures along the way.
Picture of the label on the bag with all of the specs:
There really aren't that many parts to assemble on one of these antennas:
The heart of the antenna is the hub. The bottom half that mounts to the mast is aluminum and the rest is stainless steel in between an insulator. The two allen screws on the side tighten the hub to the mast.
First mount the hub on a mast of some type to assemble the antenna. I have a small tripod and piece of mast for working with antennas on the ground:
First screw in the top 8 elements:
Now add the bottom elements and you're done with the assembly!
Here's the antenna mounted on 10 feet of mast on my roof:
As you can tell, the antenna is really simple to install. I already had the mast and coax run (a different antenna was in its place) so the whole procedure took at most 30-40 minutes, if that.
In addition to monitoring various bands, I'll use this antenna to transmit on 2 meters from time to time. I hooked up the analyzer at the transceiver to check the SWR and here's what I found:
At 144 Mhz:
At 146 Mhz the SWR spikes:
At 148 Mhz:
I've already been using the antenna to listen in on the local 440 repeater and have talked a bit on 2 meters. Remember, these antennas are unity gain and exhibit a fairly low angle of radiation.
Every ham needs a discone!
