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Reviews For: Diamond CP-610

Category: Antennas: HF: Verticals; Wire; Loop

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Review Summary For : Diamond CP-610
Reviews: 10MSRP: 239.95 in the US
Vertical dual-band antenna for 28 and 50 MHz. 5/8 in 28 MHz, 2x5/8 in 50 MHz.
3.4 dB 28 MHz / 5.5 dB 50 MHz
500 watts SSB, 200 watts FM.
Product is in production
More Info:
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
W6CJ Rating: 2023-04-30
Diamond Does Not Respond - No Customer Service Time Owned: 3 to 6 months.
I ordered a Diamond CP-610 from HRO. I liked the idea of being able to operate on both 10 and 6 meters with a single antenna.

The "instructions" were a joke. I don't know why some overseas companies don't hire a proof reader before inflicting their gibberish on the consumer. Aren't they proud of their products?

I got through the assembly without incident and temporarily mounted the CP-610 on a 20-foot push up mast, in order to sweep it using a Rig Expert antenna analyzer.

The CP-610 failed my tests on both bands:

SWR was out-of-spec near my chosen low end of 10M, and nothing like the SWR curve depicted in the instructions.

Across 6M, SWR was way out-of-spec and UNACCEPTABLE. The lowest SWR point was at 47 MHz, rather than my chosen low end of 6M. SWR on 6M rested at 2.1, but would suddenly jump to 3.5 with sudden changes in the SWR curve.

I re-checked my work, including trying alternate mast locations and alternate feedline lengths. Tests failed again.

Diamond Antenna did not respond to my repeated calls, emails and faxes.

(Disclaimer: I have installed, swept, set up or built many public safety, commercial and military antennas from MF through SHF... and am familiar with antenna analyzers, return loss bridges, TDRs, and all the rest.)

Ham Radio outlet came through. They (HRO) also had no responses from Diamond, so the store manager waived the returns deadline and shipped a replacement CP-610. I put up the replacement CP-610, ran the same tests and it met spec on 10 and 6 M.

The replacement antenna works, but I'm still giving the CP-610 a zero (awful) rating because Diamonds customer service does not exist. I will probably stay away from their products.

KD2GOE Rating: 2022-05-31
well it works and works on 20m???????? Time Owned: more than 12 months.
EDIT: after Having this up for 3 Years it died completely it will not match on 10m or 6m any more. 3:1 or higher

the most power i ever put in to this thing was 100W from my TS-2000

it gave it 6 stars now it has 0

I am running it with a Kenwood TS-2000 I was scared to get any thing from Diamond after getting the shaft from them on my Diamond X50.
I was hopping I wouldn't have the same experience with the CP-610, This time lucky for me it's working well on 10m and 6m.
10 meters has a 1:1 SWR from 28.3 to 29.9 a and 1.6 down at 28.00
6 meters is 1:1 at 50Mhz to 53Mhz the tuner can touch up all the way rest to 54Mhz
It will not tune on on the upper portion of 15m but will tune on the lower CW/Data parts of 15

it's amassing the internal tuner will load this Antenna up on 20 meters the match is real close on the upper part of 14Mhz it just needs a little touch up. ill go out and say for me this antenna works real good on 20m it blows my wire G5RV antenna out of the water on 20m. I'm not saying this will work for every one this way but I think if you have it up on a 25~30" tower like me it will work on 20m

so far I am happy with this antenna I do think it is a little expensive at $250 it shod be like $180 MAX!
When 6 meters rolls in ill update the review right now i only have some local talk to compare with 10m SSB.
KJ4TCP Rating: 2022-05-18
will not tune on 6 Time Owned: 0 to 3 months.
diamond has some of the sorriest people to work there I had this antenna for 2 -3 weeks it will not resonate on 6 meter call 5 times could not get any one to pick up or call back thy say thy have a 1 year warranty but good luck on that how can thy honor it if thy will not pick up the phone as far as I am concern don't waste your money find some one else if you do buy any thing from them I told you so hahaha
W2MRD Rating: 2022-02-26
Tunes on 6, 10, 12, 17, 20 Time Owned: 0 to 3 months.
Just put this together and tried it on a telescoping tripod in the backyard. Good SWR with my MFJ259 on 6, 10, 12, 17 and 20. No go on 15M (very high SWR). 6M was dead, but it worked better on 10M compared to my low wire antenna. I was able to make FT8 contacts on 12, 17 and 20...but haven't made detailed comparisons yet.

Inside assembly took about an hour...including the time to drill a set of holes that the factory missed drilling (to line up with the holes of the section that was sliding in to it). Instructions were not great...but it wasn't a complicated assembly so it still "made sense".

When it warms up, I'll paint it green to blend in and try to come up with a fixed mounting.
WD4AB Rating: 2019-01-18
Excellent Performer Time Owned: 6 to 12 months.
I purchased this antenna to work 6 meter FM and SSB plus 10 Meter SSB and FM. Assembly was easy and so was the tuning. The antenna performance is simply amazing,59 +20 signal reports on 6 and 10 meters are frequent. The big surprise was that this antenna will load on 6 thru 40 meters using an outboard tuner very easily with excellent transmitted signal reports and great reception, just go to QRZ and see my logbook. Excellent performer and I will highly recommend this vertical to all my friends.
K6WGX Rating: 2017-06-22
Works for me - quieter than my dipole Time Owned: 0 to 3 months.
I was able to assemble and mount the CP-610 in a little over an hour. I wanted to add 6 meters and keep my 10 meter ability so I replaced an old 10 meter vertical. The antenna is tuned by varying the length, also the 10 meter radial needs to be tuned. The measurements are in the instructions so all you need is a tape measure. You will need a couple of screwdrivers and wrenches for the assembly. Mine had 10mm bolts and both straight slot and Phillips screws.
I set it up for the lower end of the bands per the instructions. My analyzer picture mostly looks like the sample in the instructions. Mine works well with a tuner on 20 and 30 meters. I do have a 40 meter ground mounted vertical within about 30 feet so maybe the ground radials from that help. Using 6 meter JT-65, I was able to get about 2db improved signal on a reporting station about 100 miles away, over my dipole. This is noticeably quieter than the dipole at my residential neighborhood.
The pdf instructions from the manufacturers web site are a little faded and the picture seems not real clear, but it is not hard to figure out how it all goes together.
KX4DX Rating: 2016-03-19
Works as specified on 6 and 10 meters Time Owned: 0 to 3 months.
I just purchased this antenna to use with my Yaesu FT-8900R in conjunction with the Comet CF-530 duplexer and the Comet CX-333 tri-band(144/220/440 MHz)collinear vertical. The CP-610 was mounted on a chimney mount 20 feet above the ground, while the Comet CX-333 was mounted 20 above the ground on another chimney 45 feet away. The transmission lines from these 2 antennas were then connected to the Comet CP-530 duplexer in the shack and then to the Yaesu FT-8900R.
The CP-610 performs essentially as indicated in the instruction manual. I assembled the antenna measurements for a 52 MHz setting(insertion length 27 cm for pipe #3 into pipe #4).
VSWR measurements using my Bird 4304A-1 indicated 2 apparent resonance points on 6 meters with a minimum VSWR of 1.59 on 51.100 MHz and 1.47 on 52.900 mhz. The CP-610 also exhibited a minimum VSWR on 10 meters of 1.23 at 29.000 mhz.
I can easily operate 3 50 MHz repeaters within 50 miles on my QTH. I haven't had any experience with 10 meter repeaters as yet, but am looking forward to such as band conditions allow.
Overall, I am very happy with the CP-610 so far!
PA3FPZ Rating: 2013-07-30
OK on 6 bad on 10 Time Owned: 0 to 3 months.
At first glance a decent antenna. Comes in a good box, with all parts individually sealed. The aluminium used is hard drawn, makes a high pitched sound when tapped. Assembly is easy, tuning is pre-set, just follow the instructions in Japanese English (HiHi). Installing it on my tower went stress-free as well, until I came to the final part, the 10 meter resonator. The thread on the resonator did not fit into the radial ring. I had to re-tap the tread. Then came the final tuning. I tried 6 meters, big smile, nice resonance on 50.7 MHz, good reception as well. A real winner, at least I thought so.
Tried it on 10 meters, no joy! I could not get it resonant anywhere. Borrowed an analyser and found it resonant on 32 MHz. No matter what I tried, I could not get it to resonate on 10 meters. Talked about it to my dealer, supposedly a known problem and within two days I got a replacement resonator. After replacing the resonator, still no joy, it was now resonant on 30 MHz and 16 MHz. I lost all confidence of it being a dualbander, also this known problem should have been explained to me on buying the antenna.

Conclusion: Great for 6 meters, definitely not anywhere else.
MM0OVV Rating: 2012-06-12
Better than expected Time Owned: 3 to 6 months.
I think this is a great antenna because it does more than it says on the packet.
For what it's worth I don't regard myself as a serious hobbiest when it comes to my radio, would like to have time to do it more but alas as things stand at the moment I can't.
Before the 610 went up I had a Carolina Windom that was in an inverted V configuration around 50 feet from the ground. It wasn't very good. Think the Windom would be a good antenna if you can get it high in a Horizontal configuration. After a storm that blew it down and my colinear I put up the 610.
Building the antenna was not a problem. Followed the instructions pretty much to a T. The main section I decided to fix a bit longer maybe 30 cm so I could catch the 11 meter band as well. SWR is 1.1 at the bottom of the 11 meter band and just below 2 at the top. The top of the 10 meters is 1.1 and just over 2 at the bottom. The 6m band has a 1.1 at the bottom of the band and below 2 at the top. However the surprise for me was I was able to match the antenna on 15m 20m & 30m and have had some good results on these bands. 20m realistically is probably the best band out with what the antenna was designed for with an SWR just below 3 without a matcher in line. Contacts mainland Europe Spain, Italy, Germany, Holland, Romania and Also Canada and the USA. The bands that the antenna is designed for I would suggest you can't get a better vertical antenna for. Managed to make a contact the other day with a station in Spain on 6m. I'm in Scotland.
EB3BRJ Rating: 2011-02-15
Excellent performer Time Owned: 3 to 6 months.
After having two Diamond DP-GH62 antennas in the last 15 years I wanted to ger the new CP-62 as it would handle more power. However I ended up making my mind for the CP-610 and donĀ“t regret it a bit.
With a diplexer I can separate 10 and 6 meters to 2 separate transceivers with great results.