On the table there are points which are not ok for me: That FM is more efficient than SSB is not correct. I have never heard that before and my own tests clearly show the opposite. JT65 is not 25 dB better CW, but 25 dB better than SSB. CW is 8-13 dB better than SSB, depending on the speech processor. But not 17 dB better.
"-12 dB ~ To protect final transistor blow out manufacturers recommend reducing power to one-fourth normal when switching from ‘intermittent modes‘ (CW, SSB) to ‘Key-down’ modes (AM, RTTY, Digital)" All I can surmise from the 10 dB stronger signals than any other CW or SSB stations on any band at any given time is that the FTwhatever crowd must be using some of the best antennas on the planet at perpetually the highest efficiency elevation over ground. Either that or they must all be located 3 blocks from me. If I find out they aren't doing that, I'm going to invest in RF final transistor futures.
These days noise levels, especially QRN, play a large part in the effectiveness of your station. If you cannot hear them you cannot work them. On most SOTA summits noise levels are much lower than near or in town. On some of the summits a portable rig working QRP into a 22° Inverted V has a big signal and you hear and work plenty of stations, so location has an effect, one which you cant do much about working from home.
Hi Dr. Flab, Let's discuss for a moment the definition of the word 'effectiveness' and just what constitutes and 'effective' signal? If we make an assumption (always a dangerous activity) that an effective signal is one that can be heard by the station that we want to contact then an effective signal will have a value in micro-Volts which can be stated in deciBells(dB) related to 1 micro-Volt. The deciBells by themselves are a ratio and unless they are anchored by some standard value may have little relevance to the discussion. A Path loss calculation determines the signal level (in dBm) that must be generated by the source (transmitter) in order to overcome all of minuses of the path. So if the noisy suburban location requires 5.0 micro-Volts (uV) of signal at the receiver input to be heard in the chosen mode on a 50 Ohm antenna, then the distant transmitter must produce sufficient power to deliver 5.0 uV to that receiver. The mode does not matter at this point because the 5.0 uV calculation has used it already. What does matter is Transmitter power out (dBm), antenna gain (+dB), transmission line loss (-dB), conversion loss from signal on the antenna to RF field strength at 28 MHz (-235 dBm?) and on HF various ionospheric and path losses like hops over water and hops over land (all -dB) until the signal gets to its destination where it is again helped by antenna gain (+dB), hampered by transmission line loss (-dB) to finally arrive at the Receiver antenna port where it must be 5.0 uV high to be heard (effective level). You may have noticed that some values were in power levels dBm (deciBell milliwatt), some in dB (gain or loss) and some in dbuV (dB micro-Volt) which is of course a voltage. But since we are in a 50 Ohm system a 5.0 uV signal in 50 Ohms can be converted to power and then compared to dB referenced to 1 milliwatt and found to be -93 dBm. So you add up all the pluses and minuses and determine what the pluses must be to overcome the losses and have enough left to be heard on the distant receiver and you have a 100% effective path for that QSO. The Next QSO will be different and the antenna pattern will be different and the phase of the moon will be different, etc. etc. So how effective is your station? 100% if you made the contact and 0% if you didn't. So all we humans can do is maximize the pluses we can control and minimize the minuses we can control and understand why sometimes it works and sometimes it doesn't. Tom K5VOU
I have a 23 foot vertical antenna strapped to the chimney on my flat roofed house, 75 feet of LMR 400 cable and an old ICOM IC 706 producing less than 100 watts. I operate only CW. Many of the contacts I make have hugely expensive enormous antennas, expensive amplifiers and just fantastic radios. Not sure how effective MY station is.
It is really hard to correct an error here - Tom K5VOU That -235 dB number was off because I put in the freq in Hz instead of MHz It should be ~32 dB.
Well, the article is what it is. But if we were overly-worried about these things, we wouldn't bother trying. The QSOs I remember aren't the ones with macho big gun stations, but the ones who are bored, in a student dorm, say, with a wire thrown out the window - in this case, using OLIVIA. Or hearing the background noise of a pickup truck on SSB via a simple HF stick antenna as it trundles across vast dusty swathes of Australia. If there's one thing I don't understand, it's why so many complain about an inability to get out, yet so few use effective weak signal modes like OLIVIA, ROS, etc. As some others have commented in the past, it seems those modes might be underused and remarkable capabilities going unrecognised, simply because it involves a degree of real person-to-person effort. On the other hand, you can compete with your own and/or others' 'effectiveness' using WSPR. The daily WSPR DX listening challenge is very interesting in that regard - and involves precisely zero human bias or wishful thinking - unless you're one of the very few who can't resist saying they're transmitting 100mW, whilst actually sending 5W (yes, really!)
Well I am a TECHNICIAN CLASS ham & using 100 watts to a 5 /8 wave vertical tuned for 10 # meters I got my DXCC for 10# meter phone last year ! Worked all contents 10# meter phone & VUCC + on Satellite ! 43 states so far on 6# meters ! 39 states on VHF/UHF via satellite ! & 68 countries on 15# meter CW & quite a few on 10# 40# & 75# meters ! LOOK OUT BIG GUNS !!! when I get my GENERAL ! 73' Phil KI6PMD..
Thanks Jeff WN1MB I hope to work you soon on the bands CW the correct wave ! By the way 15 meters right now is PLAYING like the band ! & Jeff love your QRZ & your WEB sites they are great all the best & keep up the GOOD work 73' Phil KI6PMD ..
My station has performed very well over the years, always putting thought and effort in antennas more than QRO, working the world with QRP and QRO when I have to. The most important is use the minimum power necesary but don’t be afraid to use it when you need it, and of course use what you have and can afford. If you cannot afford it due to finances and or HOA, then use what you can and have fun. There are way too many variables at play to make absolute statements as to what is effective. What an effective station is to me is one that you can afford and able to build. I worked france on 160 meters with 30 watts at 9pm last august with a 528 foot end fed at 5 feet off the ground and it was home made including a self wrapped UNUN, cost me .50 cents for the core, and 40$ for the wire. Now is that effective.
