|
New to Ham Radio?
My Profile
Community
Articles
Forums
News
Reviews
Friends Remembered
Speak Out
Strays
Survey Question
Operating
Contesting
DX Cluster Spots
Propagation
Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers
Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net
|
|
You can
write your own review of the Comet GP 15 Tri band (144/440/52 mhz) vertical ant.
|
WB1AEX
|
Rating: 5/5
|
Jul 10, 2006 18:20
|
Send this review to a friend
|
|
Excellent Performer and Reliable
|
Time owned: 0 to 3 months
|
I have my GP-15 installed at the top of my tower, where it sits at 70 feet. The performance on all three bands is exceptional. On 2 meters and 440 the match is excellent, under 1.3 : 1 across all the FM phone portions, and the performance is outstanding. I have a GP-6 mounted about 30 feet lower, and the GP-15 outperforms it. My point here is that in spite of its slightly higher gain figures, I would never trust the 2 section GP-6 up at the top where it would be subjected to a lot more stress. However, the single section, unjointed GP-15 seems ideally suited for this assignment. Having read the reviews about being extremely narrow banded on 6 meters, I was a bit skeptical about how it would work out. At any rate, I pulled down the trusty old Cushcraft AR6 and installed the GP-15 with all new LMR400 feedline from the feefpoint down to the station 150 feet away. Any concerns I had were gone when I worked some friends on ground wave on 6 meters. Using the counterpoise whip exactly as it was adjusted from the factory, it was completely flat at 52.525, and signals were 2 to 3 S units higher than with the old AR6. The match could not be better for the FM portion of the band. I did an SWR sweep from 54 to 50 mhz and found that it plotted as follows:
54.0 mhz 1.20 : 1
53.5 mhz 1.15 : 1
53.0 mhz 1.00 : 1
52.5 mhz 1.00 : 1
52.0 mhz 1.15 : 1
51.5 mhz 1.15 : 1
51.0 mhz 1.30 : 1
50.5 mhz 1.90 : 1
50.0 mhz 2.30 : 1
It definitely performs great on the FM portion for which it was designed, and it outperforms my old AR6 monobander in all directions on 6 meters. It is a perfect antenna for my FT8900 for use on VHF and UHF. I would also add that it works great when used for scanning the aviation and public service bands. The short story is that I am really pleased with the construction and performance of this antenna and would recommend it without reservation.
Rob WB1AEX
|
|
W1FEH
|
Rating: 5/5
|
Feb 1, 2006 17:25
|
Send this review to a friend
|
|
Does what they claim it will do.
|
Time owned: 3 to 6 months
|
I have had the GP-15 up since last August. It shares the top of my 35’ tower with a GP-3 (digi) and a Diamond D-130J discone (scanner & test). They are mounted on three Max Gain Systems / IDC Technology SA-1 side arms and are plugged in 9913 coax and I.C.E. lightening protectors with many ground rods. All do what they claim and get a “5” rating from me.
The GP-15 went together easy. Always use coax seal then tape over it. I adjusted the counterpoise to the chart and up it went. SWR on the voice portion of two barely lifts the meter and on 440 the meter moves even less. I put an antenna analyzer on it to check the 6m performance and it centered just below 52.525 (FM calling). Yes it is narrow banded on six and if you want to use it away from the FM portion either mess with the counterpoise, use a tuner or use an antenna designed for that part of the band (horizontal). The GP-15 is doing what they claim, FM voice chunks of 2, 6 & 440. It performs great on all three bands and is built strong.
73,
Fred // W1FEH
|
|
KG4TDM
|
Rating: 5/5
|
May 17, 2005 08:38
|
Send this review to a friend
|
|
Best all-around VHF/UHF omni
|
Time owned: 6 to 12 months
|
Have had the GP-15 up since last November. Up about only 15-20' on a TV pole. Great ears on 2m/440 and 6m. 6m just opened up while I was listening, and made a SSB contact with NG4C in FM16 in North Carolina! This was with only 50watts and was 59.
I run and participate in emergency nets in Miami, and this is a great antenna for running and participating in both repeater and simplex nets.
All around, this I think is the best all-in-one VHF/UHF omni you can get with 6m. The key to excellent performance is having a good ground (2 separate 5' ground rods) and good coax ( I used RG-213 50'). For 6m, make the radial (stinger) a bit longer that what the instructions recommend. Also, I used coax seal on all the coax connections.
73,
Tommy
KG4TDM
|
|
KG6WLS
|
Rating: 4/5
|
Apr 12, 2005 15:48
|
Send this review to a friend
|
|
Good antenna for the price
|
Time owned: 3 to 6 months
|
I live in a dreaded CC&R enviroment and I was looking for a 6 meter vert. antenna that was light weight, easy to errect and deploy by myself, and wouldn't cost a whole chunk of change. A local ham (NJ6F) recommended that I look into the Comet GP-15 tri-bander.
Assembly was easy, however I felt that on 6 meters it had a very narrow band width. I got it mainly for 6 meter FM/repeater work here in my location and use for USB as well. My Icom 746 Pro could tune this antenna for the FM and USB portion of 6 meters with no problem. For my Icom 706MKII, (which is my back-up rig) I use a LDG-100 Pro tuner. The LDG -100 Pro would only tune as low as 1:7 SWR. Yes, I'm picky!! I've built several 2 meter and 6 meter loop antennas out of 1/2' copper pipe (K0FF's design) and I try to tune them as low as possble.
Using a Vectronics 584B analyzer set for 53 MHz. I found that the 6 meter radial portion was too long and did not wish to trim it down. So, I used a piece of ceiling wire and cut/tuned it to a flat SWR. The length came to 13 1/2", measured from the set screw to the tip. For 50.200 MHz. I used the stock stinger that was supplied and achieved a flat SWR. The length came to 28 1/8" from the set screw to the tip for that portion of the band.
At only twenty feet up in the air, I get excellent reports with it. Great 2 meter and 440 coverage with 6.2dB and 8.6dB respectively.
I know that most out there have their antennas up in the air for good, but I felt that my experience was worth sharing. Tune it how you want or let the auto tuner find it for you.
73
|
|
K6JJB
|
Rating: 5/5
|
Jan 28, 2005 18:11
|
Send this review to a friend
|
|
Great antenna
|
Time owned: more than 12 months
|
|
No corrosion after more than 6 years outside. All specified Tx bandwidths verified.
|
|
KB1GBR
|
Rating: 5/5
|
Mar 19, 2004 14:32
|
Send this review to a friend
|
|
Great antenna, Great price
|
Time owned: 0 to 3 months
|
|
This antenna performs very very well.I have had it installed about a month and have made many good contacts.Its mounted on a 30 ft.mast and I run about 125ft. of #9914 coax to the antenna.Even with all that line loss, It still cranks out the signal.The radio I am operating is a ft100d w/an EQ and a Heil GM5 mike. 73's MARK KB1GBR.
|
|
WV9G
|
Rating: 5/5
|
Feb 18, 2004 00:55
|
Send this review to a friend
|
|
Nice antenna!
|
Time owned: more than 12 months
|
|
I've had my GP-15 for 3 years, and have found it to perform flawlessly and remain intact and reliable even through several wind storms. It has good SWR on all bands, and I don't know what people expect, but even on 6 meters it is 1.8:1 at the top and bottom of the band and shows a perfect match for over 400 kcs in the FM portion. My Pro2 tunes it perfect all the way across, and my MFJ SWR analyzer says it is super on 2m as well as 440 MHz band. I work the FM repeater in Goshen, IN from Marion, IN with it.
|
|
KB9YTA
|
Rating: 1/5
|
Feb 2, 2004 19:20
|
Send this review to a friend
|
|
don't get what you pay for
|
Time owned: 0 to 3 months
|
I got the comet gp-15 in december 03.
Very narrow bandwidth
70c over 3 swr from 440-449 mc!
Although at 438 mc a 1.2 swr.
2meters 145-147 1.5 swr 144 over 3 swr.
6 meters about 500 kc tunable outside that over a 3 swr.
I bought this antenna from aes milwaukee.
I told them it was junk they told me for a replacement to call ncg and so i did and they wanted me to take the antenna apart "breaking the water tight seals" and mail them the coil.
I will never buy another comet its overpriced even if it worked on 70c.
At 177 dollars what a rip off.
Homemade copper j-pole works much better!
|
|
N8PEP
|
Rating: 3/5
|
May 29, 2003 16:12
|
Send this review to a friend
|
|
Good antenna for 2m and 440; poor for 6m.
|
Time owned: 3 to 6 months
|
|
This is a well made, very sturdy, yet lightweight antenna that is easy to mount. It is of one-piece fiberglass construction. It tuned up well on all three bands (SWR <1.8:1 on all bands), and performed very well on 2m and 440. However, when I worked 6m FM, it was not even as good as my 6m 1/4 wave ground plane. I was very disappointed since I purchased the antenna specifally for use on 6m FM. The poor performance on 6m is the ONLY reason I did not give the antenna a "5" rating.
|
|
N3HSH
|
Rating: 4/5
|
Feb 18, 2003 12:28
|
Send this review to a friend
|
|
Great in some aspects, fair in others.
|
Time owned: more than 12 months
|
I found this antenna to be sturdy, durable and a good performer except for difficulties tuning the 6m band. It seemed to work much better for me on 2m and 440. Perhaps a longer counterpoise as others have described would have resolved my problem.
After several years of service the antenna has fared quite well.
|
|
If you have any questions, problems, or suggestions about Reviews,
please email your Reviews Manager.
|
|
|
|
|
