Antenna Switching

One of the most important things in a multi station environment is certainy the flexibility of the antenna switching. We have been discussing for a long time, what would be the best for what we need in terms of antenna switching and we found a lot of brands and techonologies avaialble on the market.

From high end antenna switches from 4O3A (which features IP control over LAN) to the simplest forms of relay switching you really need to define what you need for your station layout and mainly to the category you aim compete.

What most of the contesting community does not know is that a very competitive product is available from Brazil. The Hamplus ind. from Brazil provides a wide range of antenna switching matrixes, band decoders with proven quality, being in use in the biggest stations in Brazil such as former PW7T for years.

The Hamplus owners, PP5CFS and PP5MS are very gently and offer a great product support. Below there are some pictures of our recent aquisition of a 8 antennas x 2 radios switching and 2 band decoders from Hamplus.

Proudly made in Brazil.

 

A-Ha! A Operation Desk!

Since our last operation from PY0F, during the CWWW CW 2017, we have been looking for suitable operating desks for the station. Since we have limited space for operations (the station is located inside a shipping container), we have to optimize all space available.

While waiting my wife shopping at Walmart Mall in Recife, I found up with a good option for the operating desk. These are demountable desks used for outdoor activities. Got it with a fair price for its size – 1,50m x 0,60m, enough space for a station. We got 2 of it for about 110 USD.

Stack Match Box Testing

Today we had some time for getting a look inside the stack match box by WX0B – Array Solutions.

Although we will not use it for stacking purposes (since we do not have high enough towers) it will help us during the multi direction propagation opennings between Europe and North America.

Multi direction switching is very desirable in huge pileups, when propagation seems to open in two or more directions. Switching to a specific direction, improves the gain to that direction AND attenuating signals from all other directions – that improves a lot the capacity of the operator to pick up the signals in a very noisy envoirment meaning higher QSO rates.

During the tests, the unit worked properly and all the contacts seemed in pretty good electrical conditions nevertheless the overall signs of the years up on the tower.

Some photos:

73,

Renner, PY7RP

Antennas ready to go!

Finally the antennas are packed and ready to go!.

This first pack of antennas consists of 2 x KT34XA. These antennas were made by KLM in America (nowadays these antennas are manufactured by M2 Antennas). One of them we bought it in second hand conditions and the other one in almost MIB (Mint-in-Box) conditions… for over a decade stored!.

A great effort was needed to check all parts before packing them (they are a lot per antenna! – over 100 items per antenna). The used KT34XA had some parts that got to be replaced and it that delayed our work.

The KT34XA is such a great antenna. They were a very common high gain antenna on in mid 80’s up to 90’s. It design was developed after KT34A – which is still in production and owns a 5/5 review at eHam.net. The difference between both antennas are the implement of 2 new directors elements on the XA model, which improves the gain of the array in 2,5db.

Besides the improved gain, they are heavy and long antennas. Each KLM KT34XA weights over 30 kilos and have a boom lenght of over 9 meters long. The gain is really impressive : a 9dBd on each of the 10-15-20 amateur radio bands.

We had to build a strong wood box for transportation of those antennas. The shipment weights more than 70 kilos!. We hope to dispatch these beauties very soon to Fernando de Noronha Isl.

Photos:

The “never used before” KT34XA

Ready for transportation!

Job done by (L-R) PY7BR-Jean and PY7RP-Renner

The second hand KT

Wooden box for transportation

Everything fitting the box!

 

Thanks for visiting!

73 Renner, PY7RP

CQWW CW 2017

Hello Contesters!

This was our first contest from Fernando de Noronha Isl – PY0F. We got on CQWW CW 2017 with a very simple setup in M/S Low Power, everything  was arranged in the last 15 days before the contest. We used the actual PU0FDN´s station which is composed by an A4S tribander by Cuschcraft, 2 elements on 40m by PP5UA, a 1/4 wavelenght for 80m with 4 elevated radials and a 1/2  wavelength sloper for 160m. The antennas for 80m and 160m were setup on the friday before the contest! The team was composed by Léo – PP1CZ, Julio – PP2BT, Fábio-PY1ZV, Renner-PY7RP and PU0FDN-Marenga our host.

Fig.1 – PS0F Team on CQWW CW 2017

After a long working day assembling the low bands antennas under + 30º centigrades on 3º degree south latitude, we enjoyed our first night of contest with very good running on 40m despite our LP conditions. The 2 el on 40m really did a good job. Big signals coming from NA all through the night and a good running on 80m. We finished our first night with almost 900 QSOs in the log, with almost around 700 QSO´s on 40m and 200 QSO´s in a short 80m running during the early morning.

Fig. 2 – Tribander and 2 el on 40m

We did not expected any good openning on 10 meters, and in fact it did happen during all 48 hours of contest but what really disappointed us was the 15 meters conditions. The signals were not strong as usual during our morning to Europe. We expected some good runnings to Europe on 15m and planned as our main band during the day light, BUT we had to look forward on 20m. That happened also during the second day in even worst conditions.

Our propagation  experience, pointed that 15m would be the main band but with signals so weak we realized that some geomagnetic sun interference might be occouring what was confirmed yet during the contest. Some specialized sites on the internet showed high A and K indexes and a moderate geomagnetic storm occouring.

During any geomagnetic storm, all HF spectrum is influenced and bad propagation condition is usually expected. That happened specially with our main band 15 meters. Switching to 20m was a ‘must’ since runnings on 15m were really bad.

The final score represented a very unusual QSOs per band numbers since the number of QSOs on 20m was higher than on 15m. Ten meters, as usual, did not showed its face due to very low SSN (as expected) the moment of current solar cycle.

What really amazed us was the result on 40 meters and 80 meters  with our modest conditions: 1,320 QSOs on 40m – really impressive for LP (although being from a semi-rare dxcc multiplier) and 230 qso´s on 80m.

After the contest, as usual, we had time to share the experience and point out some improvements and plannings for the next contests.

This was our claimed score:

Thanks for all QSOS! Hope cu agn on next contests!

PS0F Team.