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Messages - cockpitbob

Morse Code / Re: Activation "Vértice Geodésico"
February 26, 2018, 12:16:03 AM
I enjoyed that.  Reminds me that I need to get out more.
Among other things, they probably needed to do a major redesign on the ft-817 because it is such an old design that key chips were going obsolete.  We have that problem at work on boards more than about 10 years old.  The fact that they didn't charge the enclosure at all is.a big giveaway to me that Marketing didn't tell them they needed to come up with a new product.  Still, the FT-817/8 is a helluva radio with all it can do in such a small package.
Technical Corner / Re: The $4 Chinese Pixie Transceiver.
February 15, 2018, 03:53:35 AM
Quote from: Andywragg on February 14, 2018, 07:18:17 AM
You can't polish a turd, but you 'can' roll it in glitter.

;D ;D ;D
Reminds me of the last U.S. presidential election.  When someone asked me if I was going to vote for Hillary or Trump, my reply was "You're asking me to pick up a turd by the clean end.".
Technical Corner / Re: The $4 Chinese Pixie Transceiver.
February 13, 2018, 02:16:18 AM
If you are into putting makeup on a pig (kind of fun actually), for about $5 plus shipping you can add one of the QRP guy's 7-pole low pass filter kits to it.
Nice vid Gil.  I like the white board presentation.  It made things nice and clear.

One idea for a OTP that I kind of like is the news paper.  You and your counterpart agree on something like:  the key starts on the first letter in the first column on page-2 of yesterday's Wall Street Journal.  Not as secure as something truly random, but it has exceptional convenience.  Every day the paper boy (do they still exist?) delivers your pad for tomorrow.  I've also heard of using the text from a novel (starts with 2nd paragraph on pg 132, etc).
Antennas / Re: My Take on The NVIS X-Pole
January 20, 2018, 06:05:19 PM
That looks nice.  Since this antenna requires a tuner I suppose it could be used for the higher ham bands too.  Of course they would be more for DX than NVIS, but it's always nice to have lots of communication options.

I'll have to remember this one.  Here in New England we have more trees than we know what to do with, so I could leave the poles at home and throw a line over a 15' branch.
CB / Re: Best CB radio for inside a jeep
January 18, 2018, 04:36:13 PM
Quote from: gil on January 18, 2018, 08:57:17 AM
If you want more bandwidth and power, look to amateur radio. Anyone with $15 in their pocket can study a bit and pass the exam, at least Technician and General classes. Kids in primary school do it... It's super-cheap, very easy, no excuses. Ebay is littered with cheap amateur gear, often costing no more than a new CB radio.

With a very simple mod (jump across 4 pads) I could wide-band my Yaesu FT-857 and (illegally) transmit on the CB band with 100W, along with all the Ham, Marine and military bands.  I haven't and won't do that, but it's comforting to know I could if TEOTWAWKI happens.

And to brag a little, my older boy got his General class ticket when he was 11 8).  He basically ground through the practice tests used that young, super absorbent brain to memorize the correct answers.  But, you do learn quite a bit when you do that.  Sadly, he hasn't been active since the hormones kicked in and girls, iPhones, etc became more interesting than talking to a bunch of grey haired geezers far away. :P
This is the one I have.
I got it 2.5 years ago mostly for my "engineer from birth" son.  I paid $850 for it.  It's print volume is 10" x 9" x 8".  Of course you can make bigger things in multiple pieces and glue them together.  Printers keep getting cheaper.  There's $250 kits that take about 6 hours to screw together that work very well(sorry I can't remember the names).

Bare in mind that there's no magic in these printers and often not a lot of difference between the $300 and $1,000 ones other than a pretty enclosure, display and no need to be connected to a computer.  They all have a heated print bed, 3 axes of stepper motors, an extruder and a controllable print cooling fan.  Most use the exact same set of Arduino boards and software to run them.  The good ones are a bit more accurate because they are stiffer.  The expensive ones use guide rods bigger than 6mm, but my printer with its 6mm guide rods does great work. 

General Discussion / Re: Merry Christmas!
January 08, 2018, 10:51:32 AM
Merry Christmas and Happy New Year everyone! ;D

All I wanted for Christmas was some time with the family out of the house so I could throw breakers and track down why I have S7 to S9 broadband background noise :P. 

I got my wish, but it didn't work out the way I hoped.  Last year when I threw the main breaker the S7 to S9 noise would go to S2 or less.  Now it looks like my neighbors are making noise too because now the noise only drops 1 to 3 S-units when I throw the breaker.  Having their noise mixed with mine will make it harder and less useful to find my noise sources ???.  Funny, but I'm looking forward to the next major power outage.  I'll run my house on my generator and the only noise sources will be mine.

It's a good thing CW gets through almost anything ;)
Gil, I just renewed :), a few months late.  I'm always late with this kind of thing unless I'm sent a reminder ???.  If there's any way to set things for reminders when the subscription is about to expire that will help.

Quote from: Andywragg on January 08, 2018, 03:32:00 AM
Thanks Bob.
Just out of interest, how much does it cost to print a box?
I have a 3D printer and for the common materials (PLA or ABS) it's about $0.75/oz.  It's even cheaper than you might think because for areas of an item that have a lot of volume you tell the printer software to fill the areas with honeycomb of whatever density you want.  I use anything from 20% "infill" to 100% infill.  It saves weight, materials, print time and you lose very little strength.

Printing is a slow process.  I think printing all the parts for a uBITX box would be about 15hrs of printer time.  That's OK since it takes 5 minutes to set up a print, then I just let it run over night.
For what it's worth, there are two 3D printable cases for the uBITX on thingiverse

I've made a couple cases for RF stuff on my 3D printer.  For shielding I line it with copper tape.  This makes for a very light enclosure.  12feet of 1" copper tape is only $3 on
That looks great for the price!  This really is the glory days of Ham Radio!

Give some thought to the uBITX.  It's an all HF band, 10W radio, except no box.  For $109 you get a fully tested set of boards you wire up in whatever box you want.
If you know someone with a 3D printer, there's already 2 enclosure designs posted on

If you're a builder like me, starting about a year ago I began feeling like a kid in a candy store with too much to choose from ;D
Joel, thanks!  Those are very reasonable power numbers.  This rig is looking more attractive every time I look at it.
Does anyone know how much power the uBITX draws during receive?  Battery life is important and nearly an obsession in this forum 8).