Comment opérer à partir d'un appartement

Comment opérer à partir d’un appartement ? Voici un article publié en 2003 sur le site par Dave, VA2DV

Version en langue anglaise.

A few tips for the apartment operator

After more than 5 years of operation from apartments, I have some useful advice for hams in the same situation. My experience shows that not everything will work in every situation but I am sure operation still possible even from very « unfriendly » radio location. Don’t give up and you might be able to ragchew and work DX from a rented place.

1 — When you are in the process of renting a place, always choose the top floor if possible. That leaves you with better options (possible attic installation and useful elevation from ground). A balcony is also an important thing to seek. Many types of compact antennas can be installed on a balcony and disguised as furniture. Check for satellite TV dishes around the building. Ask the landlord if you can put a small antenna for TV/FM reception .You can even tell that it is for your work… (To receive some dispatch calls…) Even better, try to make it included on your leasing document. It might save you some problems later.

2 — When you finally move in, don’t put your antennas up the first day. Everyone will be looking at you and it’s not a good idea to look like a CIA agent with your high-tech stuff. Begin with the smaller antennas: VHF/UHF. Many vertical models are real small and even a cheap discone can make the trick (BTW, if you don’t use 6-meter FM, you can remove the top whip to make the antenna even smaller). A small 3 or 4 element beam can also easily be disguised as a FM broadcast antenna. A small roof tripod with some weight at the base can be useful if you don’t have a structure to install the antennas. A short mast inserted in a medium sized flowerpot fill with concrete can also be a great solution. Try to make your balcony look as nice as you can. An antenna will be more unnoticed on a clean good-looking place than on a pile of junk. Flowers and small trees are a good way to hide your small antenna farm. If you have to make some holes for the coaxial cables, try to make them where it’s easy to repair when you are going to leave. If you have many cables to run, consider a remote antenna switch. That can save you a lot of problems

3 — Antennas for HF: I have tried almost every model of compact HF antennas. Half-wave verticals and remote-tuned mini-loops were about the best. Unless you have large space to install radials, try to find a half-wave design that uses a small counterpoise system. Some examples are: Cushcraft: R5, R7, R-6000, R-7000 and MA5V. Hy-gain: AV-620 and AV-640. There are many other models from company like Comet, Diamond and GAP but they are much bigger. Mobile HF antennas can perform relatively well but remember that they are quarter-wave designs; you will need an extensive ground system to make them work properly. Remote mini-loops like MFJ-1786 and AEA Isoloop are also great choices. If retuning several times when changing frequency does not bother you, they’re perfect. You won’t radiate like a KW in a beam but background noise will be low and the performance is rewarding. Isotrons are not to bad, but in my personal case, RF feedback on the feedline was a real problem. Tuning was unpredictable and unstable.If you have some horizontal space, mini-dipoles using Hamsticks can be useful but remember that they are mono-band antennas. The best friend of the apartment operator is a good manual antenna tuner. It can be used with random wires and can also be used to extend the inherent narrow bandwidth of compact antennas

4 — Mode and power: In the first weeks of operation, try to maintain your output power below 20 watts, 5 watts if possible. This way, you will be able to detect any interference to your own electronic equipment and prevent association of TV and stereo problems with the « new antenna » in the neighborhood. If no problems show up in the first month or two then increase your output to 25-50 watts. Just remember; there is no law forcing you to use 100 watts on every contact! 90% of my logbook is made with 50 watts and less. And I don’t even use CW! (But it’s a real good mode for this kind of setup) PSK-31 is also a great way to enhance low-power operation.

5 — Knowledge and patience: Maybe the most important thing to do while operating from an apartment is improving your knowledge about antennas and propagation. Try to find a good edition of the ARRL Antenna Handbook. There are many great books about these subjects (I found mine for a few bucks on eBay.) You can also find numerous sites on the Internet about propagation and DX information. You may pass a little less time in front of the radio but at least, you will be on the air with a decent signal.

Hope this will help, I have not covered specific information about rigs or antennas but feel free to email me with your questions.

Good luck!

Dave VA2DV