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Reviews For: Diamond CP725H

Category: Antennas: HF: Verticals; Wire; Loop

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Review Summary For : Diamond CP725H
Reviews: 5MSRP: $399.95
Description:
Diamond’s new CP725H is a four band (6M, 10M, 15M and 40M) trap vertical antenna with trap radials. Its light weight, 6.6 pounds, makes it very manageable during the installation process and will allow for a simple mast solution. It is 11.8 feet tall and the radials are 71” long and can be mounted 360 degrees around the antenna or concentrated on one side if you need to mount it close to a structure.
Product is in production
More Info: http://www.rfparts.com/diamond/cp725h.htm
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
0053.2
OE5RBO Rating: 2023-03-21
Worth the buck - but not a cent more. Time Owned: 3 to 6 months.
Bought it to use it for trial-period with a Winlink-CMS for 40/15/10m.

Assembling is easy, all iteams were matching well without any trouble. Working step by step it takes maximum a hour to have the antenna assembled, even if untrained.

I had the antenna positioned 5m over ground on a aluminium pole.

Performance:
40m...Surprisingly well. Even that the 40m radiator is very short as the whole antenna, the SWR was at 1:1,3 with less afford to adjust.
15m...Good, a SWR of 1:1,8 was reachable.
10m...Red Alert! Unable to bring the SWR under 1:2,5 without tuning and several attempts to find a better setpoint. Sent some request for assistance to Diamond: No answer/response nor any help.

The working parameters of the antenna are not influenced by rain or wind, those stay stable.

All together: It is not that big money you invest in a CP725H and you get what you are paying for. A small antenna, mechanical not that bad with usable performance on 40/15m and a bad performing 10m band.
Compared with end endfeed-wire with 1:9balun i would prefer to have the CP725H for 40/15m, for 10m i recommend any CB-Vertical as much better alternative solution.

I will disassemble the 10m radiator when replacing it for analysis what the problem might be. So stay tuned for diagnosis

p.s @ Diamond: It might be tolerated that you are not capable of granting ANY support, but not even answering Emails is rude!
VE7CEU Rating: 2008-09-14
non functionig Time Owned: 0 to 3 months.
Got this antenna 3 weeks ago, to replace my very old R5. Installed , and on 7 Mhz 2.5=1, 21 Mhz 3.5-1 swr. Covers 50 Mhz partly. Phonecalls to Rf parts in San Marcos helped not at all. Aftermarket help, or service nonexistent, costumer service is an answering machine, calls never returned. My advice is to stay away from Diamond as far you can, and have a cushcraft instead
VK2FRO Rating: 2008-08-27
Simple to assemble, light to put up Time Owned: 0 to 3 months.
I got this antenna as my first HF antenna. The stockist was packing up for a hamfest, and held this one for me (he had no CP-6's left). Easily erected by one person, just install the mounting pipe. drop the vertical section in place with the capacity hat alreay installed, then install the bottom traps. As a bonus, it tunes up on 20m as well! It covers a larger than i expected portion of the 40m band, but I cant get it down to 7085, so I'll need a tuner. Covers half the 10 m band, a good slice of 20m (which its not made for), and all of 15m. Covers half the 6m band as well.

its no beam on a 65ft tower, but as a first antenna I'm pretty happy. Covers 11mhz cb as well (with a tuner).

I was originally going to rate it a 4 because of the 40m tuning problem, but then decided it deserved to be rated a 5 because although I'll need to use a tuner to get it down far enough in 40m, I got a good slice of the 20m band, and it will tune the 11m band as a bonus. A tuner will fix the 40m band problem, and getting it to work on 11m.
KE3JH Rating: 2008-06-22
well made ruber duck Time Owned: 3 to 6 months.
Had this ant. only a few months some years ago and compared it to my g5rv. if ya like a ruber duck on HF then get this ant if not DONT GET IT. The g5rv blew it out of the water. it was made very well. easy to put up, got great swr all around. wish it worked well but it didnt so i sold it! got a gap eagle love it. 73
WB7DNU Rating: 2008-04-13
Great Antenna for the Size Time Owned: 6 to 12 months.
I purchased this antenna to mount on a mast through my garage roof. It is small and light, was easy for me to handle alone, and required no radials. It tuned very easily on 40M, 15M, and 10M but only tuned to a 1.8 SWR on the lower portion of 6M. It has held up very well all winter and has withstood some very high winds with no ill effects.

As to performance. It works very well on 40 and 15M. I have used it on the repeater frequencies for 6M and it worked well there. Using an LDG AT-100 Pro antenna tuner I have made a couple of contacts on the 50.125 MHz and it worked well there. When I made the contacts on 6M, the band was going out and the contacts faded quickly so this wasn't a very good test, but the signal reports were good considering the band conditions. I have not made any contacts on 10M because of the poor band conditions. I have listened on 80M and it receives fairly well, similarly on 20M. I have not tried to use the antenna on these bands because it wasn't designed for them.

For its size it works very well. It isn't a dipole or a beam but on 40M I am suprised at how well it works. I have made several contacts in CA using 100 Watts and they can hear me as well as another ham in town using a linear amp with a G5RV. I have also made several contacts on 15M and have received good signal reports. The antenna is only mounted about 18 feet above ground on a 6 foot mast above my garage roof so that says something about the antenna.

I gave the antenna a 5 because it is well built, and works very well for its size. It works as well or better than a dipole on 40 and 15M.