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Messages - gil

#3016
QuoteIf that makes me an elitist, so be it...

No it does not, that is not what I meant...

Gil.
#3017
General Discussion / Re: Burning Man Anyone?
September 04, 2012, 12:17:30 AM
Hello,

Thanks for joining. I am getting into solar power myself. This is my next "unreasonable" purchase: http://www.amazon.com/PowerFilm-F15-600-Folding-Solar-Charger/dp/B002LCEQPU/ref=?ie=UTF8&m=A1VOUFSIGRIGBC I like the flexible panels, but for a truck, you might want the rigid ones... I'll build the charge controller from a kit... No RV for me, but I sleep really well in a tent  ;)

Gil.
#3018
Antennas / The Antenna Dipper.
September 04, 2012, 12:07:43 AM
A well tuned antenna will make your radio hear better and reach further. It will also avoid damage to the final transistor(s) that amplify the signal to the antenna. That is why you can't plug in any length of wire to a transmitter without some kind of tuner. It is always best though to operate without a tuner if you can. Antenna length depends on frequency. The higher the frequency, the shorter the antenna, and vice-versa. The usual method of making an antenna is to leave it a little longer than required, and measure how much power is radiated versus how much power returns to the transmitter. Ideally, all the power generated should be radiated. The measuring instrument that does this is the SWR meter (Standing Wave Ratio). You plug it in between the antenna and the radio.

The problem with the SWR meter is that you actually have to use your radio and transmit a signal to find out the correct antenna length (by trimming it inch-by-inch). You can only transmit a couple seconds at a time (in case the SWR is dangerously high), and at reduced power if possible. So how do you tune your antenna if you don't have a license yet or don't want to draw attention by broadcasting while tuning? Here comes the antenna dipper!

The best way would be to use an antenna analyzer, which is a combination of radio frequency generator and SWR meter. Some models do much more, like displaying a graph. These gizmos however start at around $250. As much as some good radios! The advantage of the antenna analyzer as well as the dipper is that the signal used to measure SWR is very weak. Not much gets out.

The antenna dipper is much cheaper and works quite well. You just don't get a fancy display of your SWR. All you have is a frequency display and LED to show where your antenna is tuned.



The one I built is the "Deluxe Tenna Dipper" from http://qrpkits.com. At $85 it is much cheaper than an analyzer. It was easy to build and works quite well. You plug it in your antenna wire and turn the frequency dial until the light goes out. The frequency then displayed is your resonant frequency. That's it! If the displayed frequency is higher than you want, you need to lengthen the antenna, if is is lower, you shorten it... Nothing else to it. It goes up to about 30MHz.

The Hendricks kits are quite good (I am not associated with them), and work very well. I have built the SOTA tuner, SWR indicator and the DC20B CW transceiver. They all worked just fine. I highly recommend the SOTA tuner for low power operations (max 5W)!

I had some safety-orange spray paint left over, and it worked out well.

So, before you spend $300 in an antenna analyzer, or risk frying your new radio's finals by trying to tune you wife's clothesline, think about the simple antenna dipper. While not necessary (A $30 SWR meter works fine), it does save the experimenter a lot of time. You can leave the dipper on and look at the LED while at the other end trimming wire. No need to involve your eye-rolling significant other  ::) The LED is quite bright. If you want to tune an antenna for best reception without transmitting a signal, it is, with an analyzer, the only way to go. I found out that my CB antenna (Solarcon I-MAX2000) not only works for CB (11m), but also 10m and 15m! 10m I suspected would work, but I had no idea 15m would. Surprisingly, 12m does not..

I love building antennas and this little guy is great!

It doesn't mean I won't end-up buying an antenna analyzer (Ten-Tec sells a neat el-cheapo Chinese model with color screen), but right now money is tight, and the "Tenna Dipper" does it's job...
#3019
New To Radio / Re: So, what am I lookin at here??
September 03, 2012, 08:19:27 PM
Hello Sam and welcome aboard. If you can get them for a song, why not.. One thing to consider though would be if the batteries keep a proper charge. If you have to buy new batteries, forget it..

Gil.
#3020
General Discussion / Re: A question for all prepper hams
September 03, 2012, 04:13:12 PM
Quoterefer to people as "civilians".

I would burst out laughing if I ever heard something like that!
I don't think I could walk by a lights-and-signs car without making snazzy comments either  ::)

Gil.
#3021
Thanks, they seem to have good reviews. A bit expensive though...

Gil.
#3022
Morse Code / Re: Starting the Morse Code Board.
September 03, 2012, 03:12:40 PM
Morse Code and CW are not the same thing. You use CW to send Morse Code... You could use a flashlight to send Morse Code... CW is the radio mode, like FM or AM...

Gil.
#3023
General Discussion / Please Help Promote Radio Preppers.
September 03, 2012, 12:15:46 PM
Hello,

Radio Preppers can use your help in promoting the site. Budget for advertising is essentially zero and the site certainly doesn't pay for itself and I want to keep ads to a minimum. It is a one-man-band. So please, do not hesitate to mention us to your friends and on other prepping forums, Youtube videos, etc. Just don't overdo it, and do not send anything that could remotely be considered spam. We need to gather knowledgeable people here; it is a numbers game. Thank you.

Gil.
#3024
General Discussion / Re: The Postman Scenario
September 03, 2012, 12:05:56 PM
Hello colonel, and thank you for starting this thread here. My vote is for CW, but I trust your experience here when you say it is too slow. Maybe a good start though. I do think CW (Morse Code) is something all preppers should know. See the new Morse Code board I created last night...

I am not against data modes, but when you start adding computer, modems and such, we are leaving the realm of simple communications in dire emergencies. There might not be many working computers around.. Transporting a station composed of many devices would also not be easy, the the need arose. That said, I know some PSK31 transceivers can have everything built-in. That, I agree would be an excellent mode of forwarding messages. I guess one could build a small data station with one of those tiny PCs that cost less than $300 and a small radio... It would indeed be interesting.
Dave Benson of Small Wonder Labs used to offer a PSK31 transceiver. It is no longer there, but a replacement might be in the works...: http://www.smallwonderlabs.com/psk31_main.htm

Another thing to consider would be the Winlink system where messages are passed as emails and no operator needs to be present to copy a message. Speaking about copying, I don't think printers and their ink cartridges would be widely available in a large scale disaster, not to mention paper...

I am curious as to what ideas will pop-up here...
#3025
New To Radio / Re: Ham Radio Dictionary?
September 03, 2012, 11:50:04 AM
Hello,

I would encourage posters to place the full wording of acronyms at least once per thread, in parenthesis... I don't always remember to do so myself, but it is good practice for newcomers. I will look for a dictionary module for the Simple Machines forum software...

Gil.
#3026
General Discussion / Re: A question for all prepper hams
September 03, 2012, 09:41:33 AM
Hello,

Anyone who thinks EMP protection is overkill should read this:

https://en.wikipedia.org/wiki/Solar_storm_of_1859

Gil.
#3027
Sunflower, you make an interesting comment, and you are not the only one, about the perceived complexity of Ham radio. I say perceived, because it doesn't have to be. Although I am a programmer by trade, I do not like complex radios. I spend too much time as it is using menus and complex interfaces. I like my radios to have a volume button and tune button, and not much else! The least the better. More features does not make a radio transmit better. It does make it hear better sometimes, but bells and whistles are optional. My favorite radio, one I build myself, is the Elecraft K1. It isn't the simplest, does use menus and has a few knobs and buttons, but remains very easy to use, small, and has a very low current draw. Anything more complex, I shy away from. Let's face it, if I can't explain to someone how to use it in a few minutes, there is a potential problem there... I can't teach Morse code to someone in 5 minutes of course, but SSB (Single Side Band voice) radios can be simple too. Look at the MFJ-9440 or an old Atlas... That's the kind of simplicity I like. With the Tech exam being so accessible, why not? Sure, it's a pain to have to pass an exam and be "registered," but to practice, you need to get on the air. When the SHTF is not a good time to learn. You could use CB and learn a lot about antennas of course, but you limit yourself to one band that only allows long distance communications in the best of conditions.

By the way, other members can thank you for suggesting the "New To Radio" board, it is on.

Gil.
#3028
Morse Code / Starting the Morse Code Board.
September 03, 2012, 02:10:26 AM
Hello,

I am creating this board based on my opinion that Morse Code might be the ultimate communication mode when it comes to prepping. Sure, Morse Code is hard to learn (for me anyway) and somewhat slow compared to other modes (though that can be argued..), but it has many advantages...

- Morse code can be used not only with radio but with visual signals such as light, laser, sound, touch, the detailed list would be long.
- Morse doesn't need a lot of power to cut through the ether.
- A telegraph system is easy to set-up using new or existing wire infrastructures and insures privacy.
- Is is inherently more private than voice modes.
- CW-only radios are cheap and small, with low current drain.
- With an appropriate key and earphones, it allows to transmit messages silently.

Feel free to add more...

I use two training tools to learn Morse Code: The ham Morse iOS application, and http://lcwo.net. There are many more.

In my opinion, Morse Code should not only be preserved but promoted in the prepping community at large as a great emergency communication mode.

Gil.
#3029
That is a good idea, I will make one...

Gil.
#3030
ConfederateColonel, I agree about the importance of building communication networks in case of a "Postman" situation. The difficulty would be to establish somewhat of a standard.. II like the basic Morse radiograms. CW is after all a data mode and the availability of computers and the required software might be rather "spotty." I think that foremost, Morse should be not only preserved but promoted as the major SHTF mode. You can use it with radio, lights, banging things, visual signals, the list is endless. There should be a thread started on the subject, and I will do so when I have a minute, but if you want to beat me up to it, please do! I have a lot to do as is...

Gil.