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Reviews For: Comet GP-6 - Dual Band

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

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Review Summary For : Comet GP-6 - Dual Band
Reviews: 32MSRP: 150
Description:
Dual Band Antenna. 2 meter and 70 cm
Product is in production
More Info: http://
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
00324.3
W5GSR Rating: 2009-07-11
Great antenna for the base radio's and for my repeater Time Owned: more than 12 months.
I have two,one is used for the base radio's and the other replaced the Jetstream jtb2 that was used for my 440 repeater,the 440 side on the jtb2 antenna messed up for some reason.The swr on both GP6's is great.
N5LUQ Rating: 2008-05-30
Great Performer, Poor Instructions, Less than rigid sleeve to a Time Owned: 0 to 3 months.
I purchased the Comet GP-6 from my local ham store after lots of research. It looked like the one that would give me the gain I wanted with only two sections. When I got it home and tried to put it together the top sections male copper rod was recessed far back into the tube and would not come out. After frantic phone calls I learned that one has to slam the top section on the carpet( not on a hard surface) and force the rod down far enough so you can grab it with some pliars. It then mates up with the female lower section with two set screws, one of which was missing from my package. Poor QC here. I had to use a homebrew slotted screw to complete this phase. The coax then goes through a sleeve which is then fastened to the antennae by one bolt and a lock washer. This is not a very secure arrangement, in my humble opinion. The sleeve has two U bolts on it which then fastens to the mast. This is not near as good of a mechanical connection as was on my G6-144 Hustler 2 meter antennae which stayed up in the elements for 20 years. I related all of this to Mike Stwerdnik at Comet. He did not see any need for improvement over what was already there both in the instruction paper and in the mechanical arrangement, as he said he has put hundreds of them together.
Does it work? You bet! The performance is GREAT with the SWR at between 1.1 and 1.3 on all VHF and UHF frequencies regardless of power. It appears to be working fine.
I gave it a 4 instead of a 5 because of the mechanical concerns I have. I will let you know how it fairs in the Texas violent wind and rain storms this spring and summer. It leans a little already which I think stems from the single point connection with the sleeve....de...N5LUQ..
KI4HWC Rating: 2006-04-15
Great Antenna Time Owned: more than 12 months.
Great 2M/440 daul band antenna,I have had it for 1 year and it works great, I can get at least 50 mile in the Hilly Tennessee Area
KC0WEO Rating: 2006-04-12
Wow Time Owned: 0 to 3 months.
Being new to the hobby, my first transmission was on 2m using an FT-897 on 50w. I was reaching out over 150 miles on simplex. RST was 5/9, full quieting and contacts were amazed (and still are). My installation is a roof top tripod at 12ft with 8ft mast. SWR was 1:1 until I added an arrestor which ^ to 1:5. Last few days were windy, gusts to 25 and it appeared stable without movement.
No guys are being used as yet.

Very impressed.

Rob
KC0WEO
WB1AEX Rating: 2005-04-26
Durable and effective Time Owned: 0 to 3 months.
I was skeptical when I plunked my cash down, but quickly became convinced after squaring away my feedline and running some checks with my GP-6. This antenna has considerable gain on 70cm and 2 meters. I placed mine at about 50 feet, within 10 feet of several other VHF and UHF antennas, and it works extremely well. It has more gain on 440 and on 146 than my log periodic beam, which claims 6 - 8 db gain on both bands. Pretty amazing considering the GP-6 is providing me gain in all directions. On 70cm the SWR is flat at 443mhz and climbs to about 1.4 at the upper and lower edges that I use when accessing repeaters on 440. Repeaters that were S-7 on the log periodic are S-9+ on the GP-6. On 2 meters the SWR is flat at 146mhz and rises to about 1.4 at the band edges of 2 meters. Repeaters that were S-7 on the log periodic are at least a full S unit better on the GP-6. On both bands, I can hear repeaters that I could not hear with the log periodic. Initially I fed this antenna with about 50 feet of RG8U-95 S.I.W. - brand new stuff and decent quality but not what I intended to use on 440 permanently. No problem on 2 meters, but on 440 mhz I found the SWR to be about 1.6:1 where I operate and generally favoring the upper end of the 440 band. When I got around to replacing the RG8 with 50 feet of LMR400 the SWR curve fell right where it was advertised to be and was flat at the resonant points of both bands. If you are seeing a high SWR, as some reviewers appear to be, you might want to look at your feedline. In my case, it was definitely the culprit. Received signals were way better on 440 mhz with the LMR400 feedline. As a bonus, the antenna receives very well on frequencies outside of the ham bands. I use it with my FT897 and it hears the commercial aircraft band and the VHF/UHF public service bands very well. The Rutland Vermont weather station (120+ miles away) on 162.425 is S-5 here in north central Connecticut on the GP-6. It was S-3 on the log periodic. If you are looking for a well constructed antenna that actually does what it is advertised to do, this one will not let you down.

Rob, WB1AEX
NT9E Rating: 2004-04-06
Superior performance Time Owned: more than 12 months.
I've had my GP-6 since Nov 2002. I've installed it with the tip at 55 ft and can work anyone I hear.
SWR Bandwidth (at my installation w/Comet MX72N duplexor)
420-450 1.5:1 or less
144-148 1.7:1 or less
147-148 1.6:1
145-147 1.7:1
144-145 1.2:1
K9DRX Rating: 2002-06-30
Not bad for the price Time Owned: 3 to 6 months.
My SWR readings after the antenna has been up for 4 months:

144 1.9:1
146 1.6:1
148 1.9:1
150 1.4:1
154 3.0:1
440 2.8:1
442 1.8:1
444 2.1:1
446 2.5:1
448 2.0:1
450 1.5:1
455 1.5:1
460 2.1:1

I must say it has been better at times. It may be the hot/humid weather we have currently. Nearly FLAT SWR at 460 and 146 in the past. 440 has always been higher around 2 to 2.5 but still not that bad considering how wide-banded this antenna seems to be. I also get very good SWR on VHF Marine band with it. It may not be the best dual band Ham antenna available, but it's ability to operate a huge spectrum of frequencies with less than 2.5:1 is greatly desired. I am very happy with it. I have no problem accessing 440 repeaters at 10 watts 80 miles accross lake Michigan. 2 Meter is always good and so far I can't complain. Obviously, there are better antlers out there but for the PRICE, this antenna shouldn't be put down.
KG4NDC Rating: 2002-02-24
Good for the price Time Owned: 0 to 3 months.
I don't understand previous reviews but here goes-149mhz.1.5:1, 144mhz.1.2:1,146mhz1:1 148mhz1.2:1,150mhz1.5:1.all in all pretty broadbanded with excellant results.haven't tryed 440 yet. Can work repeaters in excess of 70 miles.Go ahead and buy it! 73's Bill
KC4FWC Rating: 2002-01-02
Decent for residential use Time Owned: more than 12 months.
GP-6 will work fine, but is fairly narrow banded on VHF (which is OK for most people).. But I would not recommend putting it at a remote repeater site. The groud radials break off from ice, or birds. Kinda flimsey but fiberglass can be stronger than it looks. Duplex noise on repeater operation can be an issue if the joints are not tight. Also, beware, the 200 watt power rating is for SSB! This means 70 or 80 watts total power on FM. Tricky, isn't it. But overall, using an IFR-1200 serive monitor and a laboratory environment for testing antenna gain and pattenn, 3.0 dBd on VHF and 6.0 dBd on UHF. Overall a nice performer for the ham who wants a simple antenna and fairly good performance at their residence.
KC0IWV Rating: 2001-10-24
Upgrade my previous post Time Owned: 6 to 12 months.
This is an update to the previous post. I am upgrading my rating after working with Comet's excellent customer service department.

I found out that the antenna had a loose solder joint on the lower part of the internal antenna rod. The lower section of the rod had pulled away from the upper portion. This was what was causing irradic SWR on 2 meters.

I can't say enough about how good Comet treated me in their service department. I delt with Mike Stwerdnik who replied to my e-mail immediately. He gave me very good advice on what to check on the antenna.

He then sent me out two replacement screws and offered to take a look at the loading coil if I sent it in to him. He was very helpful to me in diagnosing the problem.

I ended up buying a GP-15 tri-bander to replace the GP-6 and now plan on selling the GP-6.

Both the GP-6 and GP-15 are working with excellent results. I can't tell you how important customer service is to me in product loyalty. I will continue to be a loyal Comet customer from this experience.



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Earlier 3-star review posted by KC0IWV on 2001-10-22

This antenna is a mixed bag. It is excellent on 70cm with almost 1:1 SWR across the band and high Gain. 2 Meters is a different story. I find SWR ranges from 1.5:1 to 3.5:1 depending on what portion of the band I'm using. Don't know why but it is very spotty. (It has dawned on me that it might even be a defective antenna)

All in all it works fine for local repeaters but I'm not that thrilled with the SWR situation on 2 Meters. (I have checked everything multiple times)

The assembly instructions are hard to decipher and it is somewhat difficult to tune.

On the positive - the antenna is light and durable and has held up to some horendous weather in Minnesota. Due to it's light weight it does not need a very strong mast.

I give it a "3" rating for it's mediocre 2 meter SWR performance.

If you are looking for a vertical to hit the local repeaters and aren't too concerned about supuer low SWR and going long distances - this may be a good price performer.