Manager


Manager - NA4M
Manager Notes

Reviews For: Comet GP-98 Tri-Band Antenna (2m, 70cm, 23cm)

Category: Antennas: VHF/UHF+ Omnidirectional: verticals, mobile, etc

eMail Subscription

Registered users are allowed to subscribe to specific review topics and receive eMail notifications when new reviews are posted.
Review Summary For : Comet GP-98 Tri-Band Antenna (2m, 70cm, 23cm)
Reviews: 6MSRP: 199.99
Description:
GP-98

Tri-Band 146/446/1200MHz
Gain & Wave:
146MHz 6.5dBi
5/8 wave x 2
446MHz 9.0dBi
5/8 wave x 5
1200MHz 13.5dBi
5/8 wave x 12
VSWR: 1.5:1 or less
Max Power:
150W/100W 1200MHz
Length: 9' 8"
Weight:
6 lbs. 10 ozs.
Connector:
N-Type
Construction:
Heavy-duty fiberglass, 2 sections
Product is in production
More Info: http://www.cometantenna.com/products.php?CatID=1&famID=5&childID=5
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
0064.5
KK8ZZ Rating: 2020-08-16
Great Antenna for Icom IC-9700 Time Owned: 3 to 6 months.
So far this has been an efficient, sturdy antenna that has held up to severe summer heat and several hard storms. SWR is acceptable on all three bands, but rises above 2:1 from about 146.15 to 147.00, the prime US repeater zone. Nevertheless, switching to this from an 8-element 2m Yagi gives me a lot of versatility and I don’t have to rotate the Yagi for different repeaters, or not rotate it for best signal strength while working hf at the same time in a different direction. I chose the GP-98 over the less expensive GP-95 for the extra gain.
W8MLD Rating: 2013-03-28
Very tough and good performer for the money Time Owned: 6 to 12 months.
I bought the Comet GP-98 early last fall, because my only VHF antenna at the time was a home brewed 2 meter ground plane made out of an SO-239 and brass rods. It was a great antenna for 2 meters, but my Kenwood TS-2000X also had 70 cm and 23 cm. I used 3 LMR400 jumpers to a Comet CFX-4310 triplexer with 100 feet of more LMR400 to a mast on the roof of my house. The GP-98 is at about 30 feet. It has quite a bit of gain over my home brew ground plane. From my QTH in Lima OH I have no problem talking on the WC8OH repeater in Dayton; which is over 60 miles away, or the repeaters in Findlay, Defiance, Fort Wayne and Columbus (Columbus when conditions are right for ducting) on 2 meters. I have also used it on 2 meter SSB with decent results. On 70 cm my range isn't as good as 2 meters, but it is at half the power. Still, I easily make it clearly into repeaters 40 miles away. I've had one 23 cm SSB EME contact on it, but it was very very weak, and the other ham had a difficult time hearing me as the 23 cm module in the TS2000 is only 10 watts. Plus with loss in the coax my ERP was probably only 5 watts. There are no 23 cm repeaters in my immediate area to test it's performance on those. So far it has survived 65+ mph winds and some moderate icing. I used N connectors on the main feedline to the antenna. I am hoping to be able to make a contact with the ISS with this antenna if I can catch them transmitting on a fly by. I figure if I could with the 1/4 home brew ground plane then the GP-98 should be no problem. Overall it is a fine tough antenna, and well worth the price. My tower is going up this spring and the GP-98 will be the top antenna on the mast; unless I get my hands on a Bencher Skyhawk before the tower goes up
KF6HCD Rating: 2012-11-18
Best fit for my needs Time Owned: more than 12 months.
I'm using one with a 10 foot mast on top of my 2nd story apartment (landlord is cool that way), so the base is about 35 feet off the ground. I enjoy operations on 2M/440 Simplex and Repeaters all over SoCal with some contacts from Orange County to the High Desert (Lancaster) on occasion.

Lightweight and sturdy enough for the temperate climate. It has been rained on and blown around, but still works just fine. Nothing has worked loose or corroded, so I call it a win.

I bought it used in "Like New" condition. I'd recommend it to anyone.
G4TCU Rating: 2012-01-20
Good all rounder Time Owned: 6 to 12 months.
I installed one of these as a direct replacement for a Diamond x300 dual band 2m/70cm collinear.
In appearance it's almost identical yet has 23cm.
I made a lot of measurements on the Diamond collinear before the swap over. Once the Comet was in place, (same pole, same feeder), I checked the signal levels, the Comet was equally as good as the Diamond on 2M and 70cm.
It's been up for 6 months now and I've had no problems, good swr on all three bands and the neighbours didn't notice any changes.
VA7LWE Rating: 2009-08-04
Nice antenna... shame about a plastic stress fracture in mine Time Owned: 0 to 3 months.
Just installed a GP-98, which appealed because of its high gain and support for 23cm.

I agree with W9HAT that the instructions could be a little better. In particular, I was unsure whether I was supposed to slide the upper section radiating element down inside the fiberglass tube in order to mate it with the lower section element. I had to exert quite a bit of force before the whole inner element moved in the outer tube, and in the absence of definitive instructions on the matter, I was concerned that I might damage the antenna. Nevertheless, this was really the only way the two radiating elements could be connected and sure enough with sufficient force, the upper section moved enough for me to make the appropriate connection.

The one other issue I had with the product construction is that the two halves are physically joined with a plastic compression fitting that screws together while compressing a rubber grommet for waterproofing. Either my antenna had a defect, or I slightly over tightened this fitting, because a couple of days after assembly and while the antenna was still lying on the floor, the ambient temperature reached the low 30's celsius, and I heard a loud crack. On inspection, I found the plastic fitting had cracked under stress. This was easily 'made good' with some glue, self-amalgamating and vinyl tape and a few nylon zip ties to hold it together, but even so, I'm a little peeved that the product failed in this way with what was only a hand tight fitting - albeit at essentially the full ability of my grip.

Though very early days (only got the thing up this week), the antenna does appear to be working well enough - further time and testing will tell more fully. Overall, with the exception of the failed connection the antenna seems well made and will hopefully provide years of service.
W9HAT Rating: 2007-05-29
Fine so far... Time Owned: 0 to 3 months.
I bought this antenna at the Hamvention in Dayton in May 2007 for $160. I mounted it above the roof of the house at a height of about 25'. The unit assembles easily and the hardware seems good. Instructions could be a little better but overall it's pretty obvious how the thing goes together. I am using the antenna with a Kenwood TS-2000X and a Comet CFX-4310C triplexer with about 40' of LMR400 coax (CQ-1000 cable from Wireman) and a good ground. Performance has been good in my limited testing. I will post more information later after I've thoroughly tested all bands and modes, but so far it's looking good.