Re: Owning A ShortWave Radio Is Once Again A Subversive Activity
Ford Model T ignition coils were commonly used and were usually acquired from the local automotive? junkyard.? 73s Sent from for Windows ?
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From: Gerald ShermanSent: Tuesday, March 29, 2022 6:21 PM To: [email protected]Subject: Re: [BITX20] Owning A ShortWave Radio Is Once Again A Subversive Activity ? Well, my 1st transmitter (1970) used a part of a used automotive air filter for some of the chassis sheet metal! ? Gerry ? Sent by the Thunderbird ? On 2022-03-29 22:11, Ken N2VIP wrote: > Weren't spark gap transmitters commonly built from car parts? >? > Ken, N2VIP >? >> On Mar 28, 2022, at 17:19, Tom, wb6b <wb6b@...> wrote: >>? >> A modern version of when Hams would build receivers and transmitters from scavenged TV parts. >? > >? >? ? ? ? ? ?
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Re: Owning A ShortWave Radio Is Once Again A Subversive Activity
Well, my 1st transmitter (1970) used a part of a used automotive air filter for some of the chassis sheet metal!
Gerry
Sent by the Thunderbird
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On 2022-03-29 22:11, Ken N2VIP wrote: Weren't spark gap transmitters commonly built from car parts?
Ken, N2VIP
On Mar 28, 2022, at 17:19, Tom, wb6b <wb6b@...> wrote:
A modern version of when Hams would build receivers and transmitters from scavenged TV parts.
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Re: Owning A ShortWave Radio Is Once Again A Subversive Activity
Weren't spark gap transmitters commonly built from car parts?
Ken, N2VIP
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On Mar 28, 2022, at 17:19, Tom, wb6b <wb6b@...> wrote:
A modern version of when Hams would build receivers and transmitters from scavenged TV parts.
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I have made more progress with the project.? I have the ATU installed in the box and integrated into the Teensy program.? The meter shows the forward power and SWR during transmit.? I am also currently displaying the tuning solution in binary.? The Teensy and the PIC18F2220 on the ATU board communicate with a serial link.  
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Re: Owning A ShortWave Radio Is Once Again A Subversive Activity
Tom,
I really like the link title of shortwave radio listening will become a subversive activity.
Signs of the times here in the good ole USA also. I build regens out of common parts scrapped from electronics like tvs,radios,stereos, etc from the thrift shops. i spend what they ask for the item,and after stripping the parts i could probably increase the cost of that $6 to $10 item by 30 with all the goodies i find.Im currently scavenging parts for a 1 fet transistor regen/transmitter. I found everything but the mpf102 . Im going to order several, so i can build several radios for each band.
73 David ac9xh gud thru hamcall,qrzcq and FCC
On Monday, March 28, 2022, 06:19:10 PM EDT, Tom, wb6b <wb6b@...> wrote:
I really liked the idea in this article of scavenging an ethernet coupling transformer from an old computer and some diodes to make a balanced mixer for a HF receiver.?
Raspberry Pi's as test signal generators.
A modern version of when Hams would build receivers and transmitters from scavenged TV parts.?
Amazing, analog capable receiver parts pulled from digital computers.?
Tom, wb6b
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Alex,
To be complete, I have an automatic tuner purchased as a kit that I had practically assembled to a few components. But, in case of use in reception alone, it will not serve me because I think it auto sets according to the TOS. (See the schematic)
In addition I also have a 50/70W amp kit to mount.?
With the nanovna and the antenna tester, I team up and arrange to be offered all this. Now all I have to do is get me a spectral analyzer. lol
cdt
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hello all, alex,
I just made one this afternoon.
It took me 3 hours to do it. Frankly, nothing
complicated and satisfied with the result (at least visual).
A nice photo: "balun in the garden" LOL
Cdt
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I had one like that when I first started out in 1979. It was 80-40-20-15 and 10. Worked very well, all over the world. I had that one, and another built for 20-15 and 10 mounted perpendicular to it and a switch I built out of a wall light switch to switch between them. I never worried about "common mode" currents, as I was new, and just wanted to make contacts. They worked very well?without any baluns whatsoever. I could check into the Tar Heel Emergency Net on 3.923 in the evenings, and once worked Belize on 3.725 at 3:00 AM local time. I also worked South and Central America on 20, 15 and 10, and had good luck into Europe.
You don't really really need a balun. Just a decent matching network - I got an older MFJ - 941B for $42 US, which works great, and I think you can find QRP matchers for even less.
Unfortunately, my ground system was less then ideal, so I had RF in the shack - at 100 watts I could burn my lips on the metal grid of the mic if I were too close. A good dround dropped to the ground rod outside my window helped a lot.
Good luck and good DX!
Alex Netherton, W5ALX
Buncombe County NC, EM85ro
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I leave the USB connected all the time for CAT control - logging and digital modes. I just didn't connect the power lead to the USB connector, so 5V never gets to the Arduino.?
No problem at all programming the Nano with only the UBITX power.
Dean
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Tim, The sbitx power is software adjustable down to a watt. I am shuffling the user interface around a bit so I can demonstrate it right way. I will post a video about it when I am done with it. - f
On Tue, Mar 29, 2022, 2:56 AM Tim King, Jr AG4RZ < king.tima@...> wrote: Farhan,
Is the output power on the sBITX adjustable?? I know the prototype is doing 40~ on the lower bands, and drops to 10 on 10 meters, based on what I've read so far.??
I aski because I plan to purchase a sBITX, and use it as my main station transceiver, which means it'll do some contest work, and being able to feed an amplifier will be helpful.
If it isn't, then I'm sure I can mod it like my uBITX with adjustable bias/band.
73,
Tim, AG4RZ
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On 3/27/2022 10:04, Gary Anderson wrote: I've experienced listening to RX while forgetting to turn on the power supply.? (not saying you forgot, just that I have)
USB 5V back feeds through the regulator on the Raduino and powers the uBITX main board.? RX is operational. I've never had that happen with mine. When I plug into the USB, it turns the display on, but I don't get any audio until I connect power. Or at least I think that's how it works, usually I plug in the power before I switch it on. Maybe I never noticed that plugging into the USB powers the receiver. I've only had this radio for a few months. It could have been a bad power connection. The power cord was plugged into the cigarette lighter jack on the power supply and may not have been pushed in all the way. -- Tom Sevart N2UHC St. Paul, KS -- This email has been checked for viruses by Avast antivirus software.
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Owning A ShortWave Radio Is Once Again A Subversive Activity
I really liked the idea in this article of scavenging an ethernet coupling transformer from an old computer and some diodes to make a balanced mixer for a HF receiver.?
Raspberry Pi's as test signal generators.
A modern version of when Hams would build receivers and transmitters from scavenged TV parts.?
Amazing, analog capable receiver parts pulled from digital computers.?
Tom, wb6b
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Farhan,
Is the output power on the sBITX adjustable?? I know the prototype is doing 40~ on the lower bands, and drops to 10 on 10 meters, based on what I've read so far.??
I aski because I plan to purchase a sBITX, and use it as my main station transceiver, which means it'll do some contest work, and being able to feed an amplifier will be helpful.
If it isn't, then I'm sure I can mod it like my uBITX with adjustable bias/band.
73,
Tim, AG4RZ
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Re: V6 CAT control via FLrig?
Update:
Never mind. I just needed to spend the whole afternoon randomly clicking things until everything worked properly. Repeatedly rebooting the PC probably helped. Sorry for the noise!
Tim
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Re: V6 CAT control via FLrig?
Update:
I went ahead and set up WSJT-X with no issues. Everything works there. When I revisited FLrig, all of the sudden the VFO info was updating, but still no PTT. Weird.
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V6 CAT control via FLrig?
Maybe I don't know how to use the search function; I can't be the first person to run into this. I can't get FLrig to key the PTT or reflect VFO info. There is a little blue heartbeat indicator on uBitx screen that appears, and the screen reloads every time I connect to the software, but there is no bidirectional control.
N8ME firmware, uBitx V6, FLRIG version 1.4.5
Settings:
Transceiver, FT-817
Proper Comm port chosen
Baud rate 38400
2 stop bits.
FLRig config screen says "connected" after I click "initialize." But again, there is no PTT control, and the frequency display in FLrig is stuck on 14.070 regardless of where the uBitx is tuned to.
Thank you for any help!
Tim NC0Q
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hello,
I found this article that fits perfectly with what I want to do. So I¡¯m going to give up making a balun with ferrite and adopt this coax solution.
I¡¯ve got 10-centimeter tube.
Both parts of the dipole are ready
Not too many precautions to take for humidity because in the attic.
In addition I have a nanovna and an antenna tester, so I could tune it (reasonably cut the wires to the right length) to get the maximum from it in reception. It will be useful if one day I made emission , while still being a little worried that it will make sparks (?). LOL
?
cdt
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On Sun, Mar 27, 2022 at 08:25 AM, Jerry Gaffke wrote:
Could add a diode between the 12v pins of the Raduino and pin 1 of the LM7805.
Agree that this is how the Raduino should have been revised. Yes, the Nano diode mod would have to be repeated per Nano, but you have to get your iron out to build another "an upside down Nano", so not much extra work while you are at it.? I don't reprogram the Nano out of the radio, and I have other ways to supply Vin if the need arises to program stand alone.? For normal use, I like having the Raduino and Display power controlled by the uBITX power switch. I can leave a normal USB cable connected without them being USB powered.? I also like not having the port available if the radio is powered off.? You would not get these features with the diode mod only on the Raduino.? My simple mod suits me well for now, may not be the best for others.? The display on the V6 is pretty power hungry when running at 5V, but that's another thread. Rgds, Gary?
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Yes, 5v from the Nano can go back through the LM7805 and power the uBitx?
main board from the USB port.? That's asking a lot from the tiny diode
on the Nano.? If you work with the Nano much, it is very handy to be able to
have it powered?from the USB port when programming it.
Could add a diode between the 12v pins of the Raduino and pin 1 of the LM7805.
That way there is no need to repeat the mod if using multiple Nano's,
and the voltage drop across that new diode takes some of the heat off the LM7805.
Protects the Raduino if somebody plugs power into the uBitx with leads reversed
(though reversed power can still damage to the main board).
One of the axial leaded 1n4000 series parts (1n4004 or 1n4007 perhaps) works fine.
Jerry, KE7ER
On Sun, Mar 27, 2022 at 08:04 AM, Gary Anderson wrote:
I've experienced listening to RX while forgetting to turn on the power supply.? (not saying you forgot, just that I have)
USB 5V back feeds through the regulator on the Raduino and powers the uBITX main board.? RX is operational.
I chose to remove the diode on the Nano that allows for the Nano to be powered from USB.
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Tom,
This fits the behavior of not having the 12V power supply connected/turned-on.
I've experienced listening to RX while forgetting to turn on the power supply.? (not saying you forgot, just that I have)
USB 5V back feeds through the regulator on the Raduino and powers the uBITX main board.? RX is operational.
I chose to remove the diode on the Nano that allows for the Nano to be powered from USB.
This is one method to leave the USB plugged into the computer and actually shut off the uBITX.
That removed diode now resides in series with R52.? Two birds with one stone.
Rgds,
Gary
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Juan Bruja
Gerard
Alex Netherton
