Am I doin' it right?

Discussion in 'Becoming an Amateur Radio Operator/Upgrading Privi' started by KJ4RZZ, Feb 15, 2010.

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  1. K0RGR

    K0RGR Premium Subscriber QRZ Page

    When the band is open, you should be able to make lots of contacts with what you have. 16' is not very high, but on 10 when the band is open, it won't matter that much. I worked lots of DX on 10 with a 25 watt mobile rig during the last sunspot cycle.

    Right now, what you're hearing is Eskip, and that will peak in early summer, when I'd expect it to be open for you almost daily.

    Meanwhile, when you do hear activity on 28.400, try moving off frequency 5-10 kHz. and calling CQ. Keep it fairly short, maybe 'CQ CQ from KJ4RZZ, Kilo Joliet Four Romeo Zulu Zulu and repeat that once, then listen. If you don't get an answer after about 10 seconds, try again.

    One of the problems on 15, 12, and 10 meters, in particular, is that you usually will only hear one side of the conversation. You must learn to ask if the frequency is in use before you call CQ. The skip zone on these bands is quite large, and you won't hear anything between your local area and the edge of the skip zone. So, a distant station can be working somebody 200 miles from you that you won't hear, so you need to ask before you blast him.

    Also, the band shifts so quickly that you can be calling CQ and suddenly find yourself in the middle of somebody's local net. This happens all the time on 10 and 6, and less so on 15 and 12.
     
  2. KJ4RZZ

    KJ4RZZ Ham Member QRZ Page

    Ok, good info. Thanks a bunch.

    Sounds like I need to use the antenna tuner in bypass (for now) and make sure my antenna is resonant. I will also get the "Simple and Fun Antennas for HAMs" book.
     
  3. KJ4RZZ

    KJ4RZZ Ham Member QRZ Page

    This is really the meat of the info I was looking for in this thread... antennas can be improved in time, but I really want to make sure I am doing things right when trying to make contact.

    I do not want to burst into a conversation that I cannot hear. Despite all of the technical details in the manuals, there is very little about actually talking. A brief mention of how to call CQ and how to respond to a CQ, and a table of the phonetic alphabet and abbreviations.

    It's proper radio etiquette which most concerns me at the moment. I will try moving off 5 - 10khz before calling CQ and be sure to ask if the frequency is in use. I had not even realized that two locals could be working the same skip and not hear each other!
     
  4. W0VYE

    W0VYE Ham Member QRZ Page

    I'm not sure what the advantage might be in bypassing your tuner, however I agree that you shouldn't need it. SWR gets way too much attention by some, IMO, but there's a limit to what your rig will tolerate. It's worth remembering that anything in the line--tuners, baluns--always costs you something. If you're not sure they're paying their way and then some, get rid of them. That's why I suggested unwrapping that coax balun.

    Many times, esp. on 20 meters, an East or West Coast station will be working another station right here in town, maybe 10-15 miles away, and I won't be able to hear the local station at all. At these short distances any communication is probably via ground wave. Absorption of ground wave by the earth increases rapidly with frequency. So a daytime AM broadcast signal can be heard as much as 100 miles out. The 160-meter and 80-meter ham bands are similar, though distances are shorter. But at frequencies above 10 MHz or so, ground wave propagation has all but vanished. If you don't have line-of-sight or some sort of "skip", there's nothing there.

    You and another local station may have a common "skip path" to a distant station, but you likely have no path to each other.

    As a matter of etiquette, it's pefectly acceptable to jump into a QSO in progress most of the time. You'll hear a lot of stations inserting only the last two letters of their call. The trouble is, this isn't legal. However, "KJ4R-Zulu-Zulu" is perfectly legal and accomplishes the same goal, I think. They won't catch the whole call, but they'll copy the last two letters, and you will have sent a complete station ID. Good luck!
     
  5. KJ4RZZ

    KJ4RZZ Ham Member QRZ Page

    Ahhhhhhhhhh this explains some of what I was hearing that I didn't understand... good tip, thanks!
     
  6. KE5FRF

    KE5FRF Ham Member QRZ Page

    KD0JXG
    posted:
    "I'm not sure what the advantage might be in bypassing your tuner, however I agree that you shouldn't need it."

    I provided a good explanation for why he should bypass his tuner. The only thing he needs on it at the moment is an SWR indication.

    "SWR gets way too much attention by some"

    In a lossy coax fed system, SWR can be a problem. Not so much so with balanced feedline as I explained. I agree that SWR is not always a bad thing, but in a non-resonant antenna situation loading feedline of 50 or 75 ohm characteristic impedance, for every foot of coax he will be losing power as the RF turns to heat. P=I(square)R

    "That's why I suggested unwrapping that coax balun."

    In an unbalanced feedline to a balanced dipole he needs something to prevent unwanted common mode currents. He does not want his coax to become the antenna itself. Unwanted currents are more detrimental than the choke. Besides, this is not a true balun with a ferrite core so there will be no loss due to permeability. It is an AIR CORE CHOKE. In this case there is no good reason to not use one and many good reasons to keep it as it is.


    BTW, the most important thing here is getting the BEST system on the air that you can. Not everyone can locate their tuner at the antenna. Not everyone can use balanced feedline. Not everyone can get their antenna 100 feet up in the air. But when you are trying to get performance on a marginal band (as 10 meters is right now), you should be doing everything possible to MAXIMIZE your system efficiency. With the right antenna system (efficient) you won't need 100 watts. As RGR pointed out, he was able to work 10 meters mobile with only 25 watts. But each improvement you make can afford you a few percentage points of dB (not in gain, but rather in avoided losses!!!!) Why throw something up that with a little more effort can be made 50, 75, or as much as 90% better?

    Oh, and this works both ways too. Your improvements will show up in the front end of your RX as well. (This is called DUALITY) You may actually find that those stations the DX you are working is talking to (that you can't hear) may actually be readable with an efficient antenna. That little advantage will probably help you with your operational concerns as well.
     
    Last edited: Feb 15, 2010
  7. KJ4RZZ

    KJ4RZZ Ham Member QRZ Page

    Ok, so I went and double checked my antenna. I put the tuner in bypass mode, and keyed the mic. In CW nothing happens, I get zero watts output unless I press the key. So I switched it to AM and set it for 10 watts while keying the mic with gain all the way down. For 10 watts, I saw an SWR of around 5:1 for my antenna in the 10 meter band! Whoops. I ran outside and cut it down 21" on each side (I knew it was a little long). Tried again, and came in at around 2:1. Then I noticed something strange... if I increase or decrease the power the SWR reading changes also.

    So how can I determine what my SWR reading really is if it's directly related to power output? I noticed handheld SWR meters have a calibrate feature, which my tuner does not have. The AT-250 manual says to transmit less than 20 watts to measure SWR, but the difference between 5,10, and 20 watts makes a big difference on the SWR meter in SWR mode.
     
    Last edited: Feb 16, 2010
  8. K2ER

    K2ER Ham Member QRZ Page

    Sometimes the SWR will change slightly (usually for the worse) when you apply hundreds of watts vs. just a few watts. But that's just the meter having more data to work with, hence it produces a more accurate full scale reading. Overall SWR should not dramatically change as you modulate power.

    A dipole antenna sized at 16.5' total length (8.25' per side) is theoretically resonant at 28.364 MHz. Close enough for rock and roll. Make sure you are close to that, preferably longer if you need to fudge it a little.

    I read through all the replies and it was clear to me, too, that you were originally asking about operating techniques. Everyone wanted to know what rig you had... (welcome to the land of well-intentioned, but distracting non-sequiturs and 1001 opinions :)).

    Next time you find yourself in that situation, either wait til the strong station is finished with his QSO, then call him directly: "K2ER, this is Kilo Japan 4 Radio Zulu Zulu. K J 4 R Zed Zed. Do you copy?"

    ...or call CQ nearby. But that is less likely to produce results on 10 meters now, however. The guy you're hearing is already busy, and there might not be anyone else out there. The band is just too flaky most of the time. And even though others might chide me for this (and I do applaud your courtesy regarding QRM), up the power to 100W and keep it there. You need all the help you can get on 10M now. 100W is not going to blow anyone's doors off.

    Good luck, and I hope to hear you calling one day!
     
  9. KE5FRF

    KE5FRF Ham Member QRZ Page

    One of the major problems with seeking "internet Elmering" (while a very good thing to have!) is that we are not there to see your meter, check your coax and soldering work, inspect your antenna location, and generally offer first hand advice. It is more preferable to have a local ham, an experienced flesh and blood Elmer, to work with you.

    I realize that you are asking questions about operating technique...but the reality is that all the technique in the world don't mean SQUAT if nobody hears you. Also, all that operating technique goes out the window when you damage your equipment. My advice is to get your equipment as optimally configured as possible, then the technique stuff will come right along as you get on-the-air experience.

    I haven't been a ham 30 or 40 years like many folks on here. But I've been doing it long enough (as well as professional military comms experience) to offer some hard earned advice. I can also offer you a personal anecdote.

    Today, I had my FIRST 160 meter QSO. Well. several years ago I TRIED a QSO, and someone heard me, but they couldn't copy my call (even CW!) through the QRN. I was using a 110 foot doublet fed with ladder line to my tuner in the shack back then, barely getting a 3:1 match on 160 meters.

    But I just today installed a remote autotuner on my current all band antenna (an end fed Zepp) The tuner is located at the antenna feedpoint rather than in the shack next to the radio. This tuner was able to match the Zepp with a near 1:1 SWR! Biggest surprise, I was hearing more stations on 160 meters than ever before.

    The same antenna would barely get a 2.5:1 match with my manual tuner in the shack. And like my old doublet, nobody heard me.

    So, you see what a vast difference improving my equipment made. This is demonstrable.

    I needn't worry about my technique or 160 meter etiquette (Gentleman's band right?) Someone heard me! Over several thousand QSOs in the log and TWO 160 meter QSOs tonight...one was a Canadian (I'm in louisiana)

    So, you see a little extra effort and planning makes all the difference in the world.
     
  10. K0RGR

    K0RGR Premium Subscriber QRZ Page

    The SWR reading shouldn't change much as you change the power level. Do you have a single needle meter or a dual needle meter? With a single needle meter, you have to first set the meter to read full scale (or to the end of the scale, not 'PINNED') with the meter in the FWD position, then switch to SWR and read the SWR. If you don't set the FWD to scale, you're not reading the SWR.

    Now, with a dual needle meter, the SWR reading is where the two needles cross. It will move up and down with the power level, but that shouldn't change the SWR reading.

    There will be a slight difference due to power level, because the diodes in the meter are not linear, so they react slightly differently at different applied current levels.
     
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