Chameleon MPAS2 antenna review

With my pending mini DXpedition to Niue in April 2024 as E6SP I will be using my Chameleon MPAS2 antenna, I thought it was useful to update my experience with what I have found is an exceptional antenna.

I am past 60 and was late to getting my amateur license in 2018 and became active on HF in July 2018. As I work from home, I found that the digital modes were compatible with working and non-intrusive to getting work done. My interest is propagation and digital modes are great for that and is rewarding chasing exotic signals.

I enjoy SSB voice but in terms of efficiency it was not compatible with working. When I originally got on air we were at the bottom of the solar cycle and it would have been easy to lose interest. I use Log4OM for logging, a Yaesu FT-DX10 and FT-991A as back up, JTDX and JTAlert for digital modes. Also, I dabble with FL-Digi for Olivia, RTTY etc; latterly I am enjoying VarAC. To get to 50,000 QSO’s since I started is about 20-25 QSO’s a day average.

Background:

I originally bought an MPAS1 model in 2018 and installed it semi permanently on a tripod at my QTH in Christchurch, New Zealand. My initial observations were the build quality was exceptional; I used the version with the mini balun versus the micro for the power handling of 100 watts on digital modes above 40m. Below 40m while the radio ATU will tune to 1:1 SWR the balun will overheat and reach its curie temperature and SWR would rise when running over 50-60 watts. On the occasion this occurred the balun would always return to normal state without issue.

The configuration I used was the MPAS2 on a tripod with the 3 supports anchored with metal tent pegs and 5 of the standard Chameleon radials in a star configuration layout. The radials were elevated and the balun/antenna were affixed to the tripod with the Chameleon jaw mount. I also used the Chameleon RF choke. I replaced the MPAS1 with the MPAS2 in September 2019 using the same radials, coax cable, choke etc and taking the CAPHAT from the MPAS1 to the MPAS2.

In 2020 I moved locations in Christchurch to basically the inner city of Christchurch at noise central. The current configuration as shown in the photo has the MPAS2 elevated on a 3 metre aluminium pole with the same radial pattern as per the original QTH.

Maintenance/Durability:

The MPAS2 has been in place at the latest QTH since June 2020. I have only taken it down once when the coupling nut between the balun and antenna slowly stripped the thread over time with wind movement stress. This was about 12 months after installation and can be attributed to having not tightened it sufficiently in the first place. While intended as a portable antenna and not for permament installation it has fared exceptionally well in the Christchurch climate with temperature extremes of -10C to 36C annually and wind gusts of 120kph not being uncommon. As per the information PDF’s available from Chameleon I used Noalox on the antenna segments and additionally a 3M transparent UV resistant electrical tape on the joints.

I anticipate when I dismantle it this week in preparation for the Niue trip all will be OK!

Performance:

Given the limitations of my urban locations and the high noise floor I find the Chameleon very quiet. At both QTH’s I tried an EFHW, two different models from a reputable supplier and was puzzled that the EFHW’s were so much noisier than the Chameleon. In the last test 40m was unusable on the EFHW despite trying different configurations because of noise, but there was no noise on the MPAS2. On each A/B test I did between the EFHW and MPAS2 signals were better on the MPAS2, and monitoring my signal on remote SDR’s invariably the MPAS2 was better. The MPAS2 works well for NVIS on 160m and 80m. These are bands that I have not focussed on.

Below is an SWR plot of the MPAS2 with a RigExpert 600, this is consistent with the resources available from Chameleon online. Interestingly, despite the expected high SWR on 160m and 80m the internal tuner on both the FT-DX10 and FT-991A will tune up to 1:1 so was usable.

Below are slots worked and those confirmed on LoTW by DXCC in Clublog which proves the MPAS2 capabilties using a maximum of 100 watts from the bottom of the world, I actively chase new DXCC entities by band slots and it is a fun challenge.

On SSB I have worked European stations where we have started at 100 watts and reduced power to 5 watts and still been copiable. Bouvet was confirmed on 17m FT8. With WAS 40m, 30m, 20m, 17m, 12m, & 10m are confirmed in LoTW.

My dear friend Bill ZL3NB who was previously WA3GLX, recently a SK, referred to my MPAS2 as the “stick.” Bill was ex-US Navy and had lived in Christchurch for many years and was on the ARRL honor roll. With his 3 element beam he was often surprised at what I was hearing, or working on the stick.

All going well I will update this review after my Niue E6SP adventure in April.

Gavin ZL3GAV/E6SP

31 March 2024. rev 1.0

Chameleon MPAS2 on 31 March 2024 cloudy autumn morning in Christchurch

ZL3GAV - Clublog Band slots worked at 31 March 2024