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It's arrived and I've made a start.

Lots of work to do but I'm out with the band tonight so I'm chilling this afternoon.
General Discussion / Hawaii , Alternative Power Source and CW
« Last post by RadioRay on June 16, 2018, 02:03:57 AM »
Once again, I enjoyed a nice chat in Morse with AH6V who lives on Hawaii.  Listening to his previous conversation, he mentioned that he is 45 miles from the volcano, so no trouble. Electrical power is no issue for him, because he has been living off grid for decades.  His antenna is a dipole, high and in the trees and my antenna is not at all good for long range, being a full wave , horizontal 80m loop up only 5 meters at the support poles, sagging to 3 meters at some points in between.  We discussed his large solar power system, which powers even his refrigeration & etc. -vs- my small sailboat sized system and the work shop/ham shack that it powered. 

Radio is simply amazing and the BEST 'communications computer' is your brain.

73 de RadioRay ..._  ._

Morse Code / Re: The One-Watt Magic Number.
« Last post by caulktel on June 15, 2018, 11:16:37 AM »

I know you are talking about CW as the mode however.....

 In 2015 I was building from scratch a Beach 40 DSB transceiver dead bug style on a piece of PCB. This radio was designed by Peter Parker VK3YE, I had just finished the receiver section, and the pre driver, and driver section, but was having problems with final amp going into oscillation, so I disconnected it. It was putting out about 300mw into the LPF measured without the final in the circuit. I was listening to a guy running a special event station aboard the Queen Mary docked in LA Harbor a distance of almost 1000 miles for my Oregon QTH while making the last connections to the mic amp stage with a electret capsule just hanging from some wires on the bench. I kept saying my call while looking at the waveform on my scope, Yep you guessed it, the guy returned my call sign and thanked me for checking into the Queen Mary. He gave me a 57 signal report with great audio. Keep in mind, I was running Double Side Band which means half of my power was going to the opposite side band, so that means I was getting out to S. California on about 150mw. You never can tell where your small signal is being heard. BTW, I had a lot of fun with that radio after I got the final amp section fixed, I made hundreds of contacts including one to Japan, all this on a bout 3 watts.

Morse Code / Re: The One-Watt Magic Number.
« Last post by solaris0121 on June 15, 2018, 10:40:12 AM »
Some interesting points there Gil - Id really like to see some of the rigs (MTR's QCX's and so on) have the option to redcuce power output.  If all I have is a 12volt battery and the transeiver is putting out 5 watts, id personally like the option to drop the power (and save some battery life ?) on the fly.   I might not always want to reach out to other continents.

As to your question about power threshold for a SURVIVAL radio then I really only need a few hundred miles distance - that might necessitate using a low, horizontal antenna for NVIS or ground wave if im high enough.
Morse Code / The One-Watt Magic Number.
« Last post by gil on June 15, 2018, 08:38:19 AM »

Trying to make a contact again with my Pixie and maybe 300mW, I recalled most of my past QRP and QRPp attempts using CW. Usually, anything a Watt and above is no trouble at all with a full-size antenna. I even made a contact once from Florida to Estonia (5K miles) using 1.3W! Even my Rock-Mite on 40m seemed to work fine, though the issue was more of a receiving one, because of the lack of selectivity. Then we get down to 500mW, where contacts are still possible, just a bit harder. Below half a Watt things become very dicey, though I have tested 100mW successfully on more than one occasion with Ray 820 miles away. For calling CQ however, one Watt seems to be the practical limit. It gets better from there on up, of course, up to five Watts or so, after which adding power doesn't seem to do much more, at least when conditions are somewhat favorable.

This brings me again to the conclusion that QRP radio designers know their business. Aside from Pixies, Rock-Mites and such, which are fun novelties, great practical radios start at around two Watts. I especially like the SW+ series (ME+ now), and of course, the Weber MTR rigs for QRO operations  ;) I would love to see a surface-mount SW+! Instead of adding current-hungry features, what don't we make radios smaller? We have the technology with SMT components. There should be rigs out there the size of a small box of matches. The limiting factor should be the connectors and controls.

Anyway, just rambling... I think a practical radio should have a minimum of around 2-3W to be safe, with 5W being great. One Watt could get the job done but I would not count on it. Below one Watt you're just having fun, and that's great. BTW the 817 with a less than a full battery outputs 2.5W and people make plenty of contacts with those, even using SSB.

What do you think is the practical power threshold for a CW-mode survival radio?

General Discussion / Re: Looking for Survival Camp Ideas
« Last post by vwflyer on June 15, 2018, 02:46:01 AM »
Agreed! Avoid real distress calls!
A simulated emergency call should have some goals to be met to prove that the exercise  was successful though. When organizations like ARES demonstrate their abilities to public service agencies, they have to show the value of the radio by proving that important/life saving communications can reliably be handled by their radios. They do this by transmitting non-important but equally challenging messages. Things like your coordinates are a good test of successful communication since it's something that can easily get messed up in the transmission with all those numbers (number don't have context to help fill in the blanks), and it's something that would likely have to be transmitted in a real crisis. It also involves other survival skills like being able to read a map or use a GPS, so it ties the radio in with the rest of the outing.
General Discussion / Re: Looking for Survival Camp Ideas
« Last post by gil on June 14, 2018, 02:00:20 PM »
I suggest not using words like "Mayday" or SOS in Morse... Even for a simulation, and even with a warning.

General Discussion / Re: Looking for Survival Camp Ideas
« Last post by vwflyer on June 14, 2018, 01:43:07 PM »
And as for simulating a distress call, perhaps you can prearrange a call with a ham you know. Have the scouts provide you with coordinates from a map or gps. Make it vary clear on the air that itís an exercise or simulation and make the information passed benign so that other hams donít get excited by tuning into the middle of the QSO.
If you can set up a 60 or 80 meter wire you can be pretty sure of solid local QRP contacts using NVIS.
General Discussion / Re: Looking for Survival Camp Ideas
« Last post by gil on June 14, 2018, 01:23:53 PM »
Morse code with flashlights! Then have them try to decode slow code on the radio...

General Discussion / Looking for Survival Camp Ideas
« Last post by N4AE on June 14, 2018, 11:40:06 AM »
Hello from Chicago.  Hope everyone is enjoying time outside, especially with Field Day upon us.

I'm looking for some ideas to incorporate radio into a survival exercise with my Boy Scout Troop.

Each December, we take to the back woods of Michigan for a weekend survival camp.  The boys dig trenches, build shelters, and sleep in the snow.  They make their own meals with limited provisions.  It's an individual effort and the boys learn that they can make it using the Scoutcraft they know.

This year, I plan to bring along my Field Expedient Station (FT-817ND, Chameleon Emcom III Portable) without digital.  Just phone for simplicity.

My first thought is to demonstrate how to build a hasty antenna deployment.  Maybe an end-fed inverted Vee.  Simulate a distress call (not sure how I will do that).  Try to make contact in the daytime (groundwave) and night (skywave).

I would appreciate any input you have.


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