The versatile Diamond CP-5HSII 5 band vertical

HA3MGA Gabors childhood dream was to be a radio amateur, but he always had more important things in his life. Finally, during the COVID lock down, Gabor thought there is was no more reason to wait and decided to do the exam. He was licensed on 2021 July with the call sign HA3MGA. Being an IT expert, he mostly likes the legacy digital modes like PSK, RTTY and Olivia. HA3MGA also became a big fan of RTTY contesting during the last year. He is active from 80 meters to 70 centimetres and from QRP to QRO.

As I remember, I bought this antenna in January of 2022. It was never deployed as initially I don't have time to do it. Later on, I changed my mind and bought a different antenna. The Diamond CP-5HS was just put behind the bed in my shack. It was completely forgotten until recently, when I started to think about a portable HF antenna. Finally, on the weekend of the SP DX RTTY contest, where I participated in the QRP category this year, I decided to give it a try as a portable antenna.

This antenna is not really intended for portable activities, but it is not so heavy and it was surprisingly easy to assemble. It took only a bit more than 10 minutes. You need only a crosshead screwdriver and a 10/13 wrench. According to the manual, only those radials need to be installed which bands will be used. As my QRP Labs QDX radio can work only on 80/40/20 meter bands, I installed only the 40/20 meter radials. This antenna can't work on 80 meters and it was a late forenoon, somewhat also late for 80 meters with QRP.

I deployed it in the garden, intentionally close to the ground and other "disturbing objects". I wanted to check how complicated it is to tune and what are the VSWR figures, if the conditions are not so good. As a second surprise, it tuned quite well! Unfortunately, I didn't not make any VNA screenshots, but the VWSR and bandwidth was absolutely according to the manual. On 40 meters it was 1:1.2 and better on 20m, as I was able to achieve 1:1.1 on this band. Tuning was very easy with my NanoVNA-F, only the length of the appropriate radial needs to be aligned with a crosshead screwdriver. It took only a few minutes to tune it into the digital segment of both bands.



After the successful setup of the antenna, I deployed my QRP station. Nothing special here, just a not so young HP Folio 13-2000 laptop running Fldigi, and a modified (forced air cooling) QRP Labs QDX Revision 3a radio running from battery. The transmission line was 8 meters of Aircell 7. I really love this cable, as it has low loss, really flexible, not so thick, light, therefore easy to handle.

I had only less than two hours for the whole experiment, and I was skeptical initially, as it is a small HF antenna and QRP is QRP. Nevertheless, I was able to make several contest QSOs across Europe on both bands. It was not bigger "pain" than doing it with my EFHW. I also heard a station on 20 meters from Puerto Rico with the Diamond. We had several QSOs from previous contests (made them with my EFHW and 50-100W ), but there was no success with the Diamond and 5W this time...

This short period of time was not enough to figure out whether it is a better or worst antenna than my low hanging (6 meters) EFHW.

The advantages of the Diamond CP-5HSII as a portable antenna from my point of view in order of importance:
  • Not depending on hanging points (trees, etc)
  • Very easy to tune or retune, no tuner necessary
  • Easy and quick deployment
  • Acceptable transport size and weight
  • No grounding network necessary
  • Lower vertical radiation angle than low hanging dipoles or EFHWs, however, the gain which is more like loss is strongly dependent on the ground quality

The transportation length is only 140 cm using the original box.

It is not really intended for this purpose by Diamond, but because of the above advantages, I decided to use it as a portable HF antenna in the future. I think it is much better to use it for this purpose than just store it behind the bed in the shack... :)

73! de HA3MGA Gabor Molnar

Send us your reports!

Secure yourself 50€ now! Share your experience with us and other customers by writing and submitting your own customer report. We'll reward your efforts with a €50 WiMo voucher when we publish your review. Your review is important to us!

Submit report now You have questions?

Share this post with your friends!