Re: New siglent on the way
Thank you guys, but I already had a series of adapters, series of of BNC attenuators, a 6 dB N rated at 2 watts and heathkit Cantenna ?with a homemade attenuator and now a commercial 50 W dummy load with a 30 DB tap
On Apr 12, 2019, at 13:20, Jerry Gaffke via Groups.Io < jgaffke@...> wrote:
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Correction:
The 2000 ohm 3 Watt resistor is Mouser 283-2.0K-RC
On Fri, Apr 12, 2019 at 09:29 AM, Jerry Gaffke wrote:
Forty 2000 ohm resistors in parallel can dissipate 120 Watts,? Mouser 283-20K-RC
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HERE IS A cap (CHEAP AS POSSIBLE) WAY TO CONNECT UbITX OUTPUT TO A SCOPE, METER, FREQUENCY COUNTER OR SPECTRUM ANALYZER
This utube sight has several videos on DIY test gear and dozens on radio repair.
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Some are looking for dummy ;load for uBitx here is watts up
W8TEE designed this dummy load and published it on a webpage (which now seems inactive.) and QST magazine
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Re: Raduino with a different SDR?
I use gqrx on my Ubuntu laptop. I've written several Perl and wxPerl applications that use the UDP interface to implement various scanner functions. The UDP interface implements a subset of the rigctl protocol.
I understand that the RPi should have the add-on heat sinks when running this application.
James
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Standalone signal analyzer
Hi guys it's Kelly I'm thinking of trying to add to Standalone signal analyzer to my ubitx. I have added a buck converter from 12 volts down to 5.1 volts at 3A. I currently have it successfully powering the nextion display. I am thinking I could run the nano for the signal analyzer off the same 5v 3A source without too much loading?? If anyone has any thoughts, I would appreciate it.?
73,
Kelly K5AID?
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I bought a new old stock Cobra CB mic for $5 and gutted it. ?I used the original switch that came with the mic and used the element that came with the uBitx kit and put a 4 pin mic connector on the cord. ?I get good audio reports with the stock element.
Curt M.
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Re: ubitx v5 down: IRF510 heatsink very hot immediately after turning on the radio
#ubitx-help
#ubitx
Hi Evan, I created a small test amplifier on a breadboard to test the uBitx LM386 in isolation. It still works fine. It was an interesting learning experience to build this test circuit: https://photos.app.goo.gl/geLNimcdm4BWw3Av6 With or without antenna I can not hear anything other than noise and a slight clicking noise when I tune to different frequencies. I can increase/decrease the volume of the noise with the volume potentiometer. This probably means the RX problem is located somewhere before the audio amplifier. I did find a 'uBitx diagnostic guide' (written for the uBitx v3, is there a version for the uBitx v5?). I will try to determine how much of this guide is still applicable to the uBitx v5: /g/GCBG/attachment/105/0/uBitxTroubleshooting%20manuala.pdf-jens
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Re: New siglent on the way
Correction:
The 2000 ohm 3 Watt resistor is Mouser 283-2.0K-RC
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On Fri, Apr 12, 2019 at 09:29 AM, Jerry Gaffke wrote:
Forty 2000 ohm resistors in parallel can dissipate 120 Watts,? Mouser 283-20K-RC
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Re: Raduino with a different SDR?
Could simply replace the Nano clone on the Raduino with a Raspberry Pi Zero.
Easier to keep all software on one processor, no need to communicate with another processor.?
Would need to port the uBitx Arduino sketch over to C on the Pi Zero, but that should be easy enough.
A high speed morse keyer might be off by a few milliseconds now and then due to
interrupts and Linux housekeeping, but I doubt most of us would notice.
Jerry, KE7ER
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On Fri, Apr 12, 2019 at 02:04 AM, Dexter N Muir wrote:
The RasPi has heaps of GPIO too - I'm wondering if the likes of a 'zero' could take some of the 'control ' and display functions from the Raduino? Would/could I^2C tie them? There must be a heap of non-critical stuff not? absolutely dependent on the microprocessor immediacy? A zero-W could give Internet remote ops too! (or has that already been thrashed and trashed?)
73
ZL2DEX
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Re: New siglent on the way
I'm not so sure there is much point in buying a special high power 20dB attenuator.
Even at 10 Watts, a 20dB attenuator would be rather expensive.
You probably already have a 50 ohm dummy load suitable for use with your transmitter.
If you plan to work on your transmitter at all, you should have a dummy load.??
A 12 Watt 50 ohm dummy load could be built with four 3 Watt 200 ohm resistors in parallel.
You can get ten such resistors for one dollar from Mouser,? part number 283-200-RC
Forty 2000 ohm resistors in parallel can dissipate 120 Watts,? Mouser 283-20K-RC
To reduce transmitter power by a power ratio of 100), must reduce the voltage by a factor of? sqrt(100) = 10.
So add a 450 ohm resistor from the top of your 50 ohm dummy load into your 50 ohm step attenuator,?
The step attenuator must be capable of dissipating 100 milliwatts if the transmitter is giving 10 Watts.
The 50 ohm step attenuator sees a voltage that is reduced by a factor equal to its 50 ohms divided by
the total resistance of that leg, or 50/(450+50) = 0.10, which is a factor of 10 as computed above.
The transmitter will see 50 ohms in parallel with (450+50) ohms, or 50*500/(50+500) = 45.5 ohms,
close enough for government work.? Could correct this 10% error by making your dummy load
look like 55.55 ohms instead of 50 ohms by adding a 1/8 Watt 5.55 ohm resistor in series with it.?
(The 5.55 ohm resistor only sees 1/10'th of the transmitter's voltage, so only 1/100'th of the power.)
Kees has a kit available for a step attenuator at a good price, kit number 13 here:
? ??
Jerry, KE7ER
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On Fri, Apr 12, 2019 at 04:51 AM, Raj vu2zap wrote:
Congrats, you will learn a lot from an analyser.
You will also need some attenuators and dummy load type power attenuators.
A 30db power attenuator rated for more than 100W will suffice even for commercial rigs. For uBitx and such
25W should do.
You will also need optionally a variable attenuator, one that has 0-9db and 0-90db steps. With this you can
set any power input to 0dbm at the SA input.
Raj
What I use is similar to this one below and this is fixed after the big dummy attenuator below. This brand will be expensive.
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? ? Enviado desde para Windows 10 ?
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Re: New siglent on the way
On Fri, Apr 12, 2019 at 05:22:41AM -0700, Curt via Groups.Io wrote: We won't hold Gordon to making great advances with the acquisition of? this nice tool, but bonne voyage on having the dBs and MHz's presented.? (Okay he is welcome to further solve the v3 and v4 remaining spurs that his nice circuit board design partly cures).?
I have a Siglent that I have been wanting to find time to throw the uBitx on. Time is something I have in short supply right now. ;) I'll let the group know once I find some time. Yes the kind of stuff Raj shows is very familiar and quite useful.? I suggest if one does not plan to do lots of work up at UHF, one can scrounge useful-enough hardware at hamfests/surplus that works at HF or low VHF.?
Iz - I recall (but never used myself) some HP portable spectrum analyzers that indeed contained analog demodulators that allowed it to function as a receiver.? These items can easily be home assembled - see if this or another spectrum analyzer contains an IF output, then you have a path to making it a receiver - even an SDR or a multi-SDR/analog receiver.? As for low phase noise, look carefully to see if it has a lower phase noise than even a uBITX -- it might be similar or only slightly better.? The ubitx hears just as well as my K2 -- both have nice PLL's (I have not put the ubitx to test with large adjacent signals but I imagine the ubitx to be pretty good).? yes get and analyze some real numbers before assuming its an advance over what you already possess).? Yes there is a demodulator on the Siglent but I have not looked into it too much yet. Time.
Glad to see enthusiasm for the radio art - everywhere around the world.?
73 Curt
-- - db@... db@...
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Re: [JackAl] JackAL source code
tors 11 apr. 2019 kl. 15:13 skrev Jack Purdum via Groups.Io <jjpurdum= [email protected]>:
All:
A long time ago, Al and I agreed to use the MIT License for our software, which says:
Copyright (c)2018, Dr. Jack Purdum (W8TEE) and Al Peter (AC8GY)
Permission is hereby granted, free of charge, by to any person obtaining a
copy of this software and associated documentation files (the "Software"),
to deal in the Software without restriction, including without limitation
the rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE. I have been remiss in placing this in the software's *.ino file, but will do so. If you plan on using/selling the software commercially, Al and I would appreciate a notice to that effect, as we would like to at least track its use.
As to modifying the software, our hope is that people will use the [email protected] site for such changes. The decision about integrating any submitted changes to the code base that we maintain shall rest with Al and I. Users are, of course, free to implement any changes they deem desirable to their own copies of the code.
Jack, W8TEE
On Thursday, April 11, 2019, 8:44:34 AM EDT, mike.carden < mike.carden@...> wrote:
Having downloaded the JackAl source code from?
a couple of questions come to mind.
1. I don'r see a LICENSE file. Is the code Open Source? If so, under what license?
2. Is there a source repository somewhere where interested contributors can offer patches for corrections / improvements etc?
Thanks,
MC
VK1MC
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Re: CW key sticking with Nextion LCD, still getting RF in
There is a uBitx "keying" board by W0EB on QRP Guys, might be relevant to your issue.
73 Jack KZ5A
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Re: New siglent on the way
We won't hold Gordon to making great advances with the acquisition of? this nice tool, but bonne voyage on having the dBs and MHz's presented.? (Okay he is welcome to further solve the v3 and v4 remaining spurs that his nice circuit board design partly cures).?
Yes the kind of stuff Raj shows is very familiar and quite useful.? I suggest if one does not plan to do lots of work up at UHF, one can scrounge useful-enough hardware at hamfests/surplus that works at HF or low VHF.?
Iz - I recall (but never used myself) some HP portable spectrum analyzers that indeed contained analog demodulators that allowed it to function as a receiver.? These items can easily be home assembled - see if this or another spectrum analyzer contains an IF output, then you have a path to making it a receiver - even an SDR or a multi-SDR/analog receiver.? As for low phase noise, look carefully to see if it has a lower phase noise than even a uBITX -- it might be similar or only slightly better.? The ubitx hears just as well as my K2 -- both have nice PLL's (I have not put the ubitx to test with large adjacent signals but I imagine the ubitx to be pretty good).? yes get and analyze some real numbers before assuming its an advance over what you already possess).?
Glad to see enthusiasm for the radio art - everywhere around the world.?
73 Curt
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Re: CW key sticking with Nextion LCD, still getting RF in
My fix for sticky controls
I have had rf on the ptt on 20. SWR was 1:1 My solution was to put a choke on the mic wires inside the box. Can imagine that using a small toroid on the key wires would help.
I use these .
I don't have hardly any shielded wire.
If you have rf on the circuit after you have put a choke on it you don't have enough choke.
I reviewed w1his articles. Had a lot of good ideas.
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Re: New siglent on the way
Gordon,
Congrats, you will learn a lot from an analyser.
You will also need some attenuators and dummy load type power
attenuators.
A 30db power attenuator rated for more than 100W will suffice even for
commercial rigs. For uBitx and such
25W should do.
You will also need optionally a variable attenuator, one that has 0-9db
and 0-90db steps. With this you can
set any power input to 0dbm at the SA input.
Raj
What I use is similar to this one below and this is fixed after the big
dummy attenuator below. This brand will be expensive.
At 12/04/2019, you wrote:
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And
Be sure that the one you get has the tracking generator
On Apr 11, 2019, at 19:20, twowindsbear via Groups.Io
<
twowindsbear@...> wrote:
How about links to the siglent
and the spectrum analyzer that you mention??
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Re: Raduino with a different SDR?
The RasPi has heaps of GPIO too - I'm wondering if the likes of a 'zero' could take some of the 'control ' and display functions from the Raduino? Would/could I^2C tie them? There must be a heap of non-critical stuff not? absolutely dependent on the microprocessor immediacy? A zero-W could give Internet remote ops too! (or has that already been thrashed and trashed?)
73
ZL2DEX
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Re: CW key sticking with Nextion LCD, still getting RF in
Happy to say running shielded wires and making sure metal contacts like mic plug is grounding to case and everything else. I am not hearing any RF in the CW delay on my antenna.?
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On Apr 11, 2019, at 2:57 PM, Joe Puma via Groups.Io < kd2nfc@...> wrote: Hi Sam,?
I had a pvc air wound one too. 21ft of coax, but it was some real crappy coax so I took it off. I will try a better one. I was eyeing an inline choke, I was thinking of getting the my antenna one.?
U have a choke on the efhw? I have a very similar set up and run into similar issues without one. I use an pvc wound coax choke.? Or, try adding/removing a couple feet of radiator line? Intermittent sucks.
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_Dave_ AD0B
Raj vu2zap
MadRadioModder