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Author Topic: Coffee Shop - Part II //  (Read 3576 times)

RadioRay

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Coffee Shop - Part II //
« on: December 11, 2012, 04:47:30 PM »
After MUCH head scratching and etc. I discovered why signals from Gil were quite readable but not as strong as they probably should be.  More importantly, my signals to him were not at all strong.  Using analysis software - and Kentucky Windage- it was determined that my 130 foot doublet antenna makes a big null right on his location and the take-off angle is too high for the prefered path, forcing us to a lower band, higher absorption and noise.  We were making useful contacts - no question - and it was quite impressively functional considering the use of expedient antennas and powers as low as 200mW..  HOWEVER - I didn't want to settle for "functional" and so designed a wire beam of a type I used a long time ago with manpack sets: the Half Square antenna. (GOOGLE)

In about two hours, I put in a quick and dirty Half Square pointed toward Gil, expecting him to be at home with his best antenna at the ready.  At the appointed time I heard his signal, switched between antennas and sure enough, about one S-unit improvement, little or no fading, while on my 'regular' antenna, he was down one S-unit with deep fades and increased noise. THEN he taps to me that he's not home running 14 Watts into his PAR EndFed, properly installed, but instead he's at the coffee shop using a BuddiStick, wedged-in among chairs, tables and frightened housewives...   ::)   using his K1 at 5 Watts. So - his signal ranged from S3 to S5 on the first test, S4 to S7 on the second about 45 minutes later. I recorded the audio and have sent it to him.

:o  ! The RF noise in an urban cyber cafe' must be tremendous !       :o

Be Warned!!!  JUST when you THOUGHT that it was safe to go enjoy a fine cup of coffee , served by a shapely 20 year old barrista...


some guy sets-up a 'coffee clandestine' radio station and begins to radiate mystery signals into the ether to who-knows-whom???   ha ha




de RadioRay ..._ ._

« Last Edit: December 11, 2012, 06:57:56 PM by RadioRay »
"When we cannot do the good we would, we must be ready to do the good we can."  ~ Matthew Henry

KC9TNH

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Re: Coffee Shop - Part II //
« Reply #1 on: December 11, 2012, 06:06:10 PM »
Actually, alot of residential backyards could support a 40m half-square, easily a 20m version. Nice option.

Great job! 
(I thought you were terrific in 'Dawn Patrol' but you need to ditch your g/f in the coffee shop)
8)

gil

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Re: Coffee Shop - Part II //
« Reply #2 on: December 11, 2012, 07:54:05 PM »
It was an interesting experiment. Probably very RF noisy indeed. Lots of cars zipping by only feet away.. I don't have a noise blanker on the K1, but it was all right. Earphones help a great deal. There might be a 10/11/12/15/17/20m magnetic loop in my future, after I build my 20/30/40m model. Trip to Home Depot planned tomorrow!

Gil.

RadioRay

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Why Do We Mention "Java Mobile" Operations?
« Reply #3 on: December 12, 2012, 02:26:32 PM »
This being a site with emphasis on alternative radio communications with possible use during emergencies, I want to emphasize that Ham radio does NOT require thousands of dollars in transceivers, towers and world class beam antennas.  Those things are VERY cool and yes - they extend your reach. (I'd love to have them, but there is this thing called 'thrift' that keeps getting in the way...) , but this coffee shop portable series of demonstrations is proof of concept that YES you CAN set-up and operate just about anywhere, with good results and by doing this as a hobby it's also enjoyable practice, should you have to set-up your portable radio station for less desirable reasons.

The idea of Gil, a relatively new ham, operating 'portable' at a table in a coffee shop is a clear demonstration that you CAN operate successfully with relatively inexpensive gear, expedient antennas in odd locations and STILL enjoy ham radio.  Naturally, what we do as a hobby/mania would become a rather powerful tool when/if ordinary infractructure based communications fail. It also emphasizes the HUGE difference that CW makes over voice.  Gil & I have done a couple of experiments in switching from CW to voice and when conditions are 'better' we can make voice contact and have fun with it.  However, just for fun, I usually sign-off in voice THEN in CW as we did today.  When Gil 'beeped' back in CW, the difference from 'weak readable' in SSB went to OUCH! my ears, because I had the gain up so high to pull-out the voice, that the Morse was quite strong in my headphones.

So - what are YOUR thoughts?  If Gil can set-up in a coffee shop and tap Morse over 800 miles to me - operating with 5 Watts (max) into an antenna leaned against a post, other diners, orders being served, cars whizzing by ont he busy street, could this serve to illustrate the use of listening/transmitting as necessary for other than hobby use?  Remember - what we do as a radio hobby, was state of the art Special Operations territory a generation or less ago in history.  Our hobby is a powerful tool.

Your thoughts?



>Ray
« Last Edit: December 12, 2012, 03:14:59 PM by RadioRay »
"When we cannot do the good we would, we must be ready to do the good we can."  ~ Matthew Henry

gil

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Re: Coffee Shop - Part II //
« Reply #4 on: December 12, 2012, 03:01:26 PM »
Our last contact today: Using my $30 DC20B from http://qrpkits.com. 800+miles on 500mW on 14060. SSB with 12W was barely usable.

Gil.

KC9TNH

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Re: Why Do We Mention "Java Mobile" Operations?
« Reply #5 on: December 12, 2012, 06:04:05 PM »
Remember - what we do as a radio hobby, was state of the art Special Operations territory a generation or less ago in history.  Our hobby is a powerful tool.

Your thoughts?

>Ray
Along with your post elsewhere about the fine time on 30m you've reinforced why in a modern no-code testing environment I dredged it back up anyway to put in the toolkit. It's always been a go-to mode. Plus, with the modern stuff you save money because one should, at least in my view, flip for the coffee of the guy cranking the G-43. Modern solar panels & battery capabilities are light-years beyond my youth.

Good to see you're having fun with it and continually proving the concept.

Radio Preppers

Re: Why Do We Mention "Java Mobile" Operations?
« Reply #5 on: December 12, 2012, 06:04:05 PM »