Re: Ubitx V3 Transmit lock
The uBiTx uses an Analog Input for the keyer circuit.? Since bypassing (shorting) the normal pull up resistor drops it out of TX, then either there is a low resistance value between the key jack tip and ground or the analog input is damaged.? If it were a complete short you would see the display flicker, and maybe damage the 5 volt supply when you jumper the 4.7 k resistor.
I would try removing the key shaper and install the original 4.7 K resistor.? See if the problem persists without the shaping circuit.? If so, then you have damaged the Nano analog input.? Try replacing the nano.
Note: if you do need to replace the Nano, you will need to recalibrate the rig, as the calibration values are stored in EEPROM and not program memory.? IF you are using the KD8CEC software, you can save the calibration values with the Memory Manager 1.11 program. Otherwise will just need to go through the calibration process again.
Has anything else changed from when it was working correctly?? Example would be a new antenna or tuner or other external components.? RF feedback has been an issue with these rigs.
Sorry to hear that you are having issues with your uBiTx.
73
Evan
AC9TU
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Re: Ubitx V3 Transmit lock
Hello,
I would disconnect the keying conditioner first.
Maybe one of the FETs is gone or there is a short circuit in the keyer cable/plug.
With no key connected you should have very close to +5v on that blue wire.
Faulty Arduino input is possible but unlikely, so would look elsewhere first.
73, John (VK2ETA)
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I built a ubitx V3 some time ago and no issues except CW keying. I built the CW keying conditioner from QRP Guys and installed it in the ubitx. Worked great and was pounding out text at about 20WPM with a straight key with no keying errors from the ubitx keying circuit. All of a sudden the rig went into transmit lock, upon investigation I found that now the keying resistor which provides 5VDC? to the keying circuit (blue wire Raduino) must be shunted to bring the ubitx back to receive mode. SSB operation seems normal but if I remove the shunt from the resistor the rig goes back into transmit lock. Any ideas?
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Again that's very helpful. Thanks for the tip on the software as well. Feel more co fident now so ordering now. Much 73
Sent from my Samsung Galaxy A3 2016 - powered by Three
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-------- Original message -------- From: Evan Hand <elhandjr@...> Date: 13/04/2020 15:50 (GMT+00:00) Subject: Re: [BITX20] nextion display
I would be careful with the 2.8¡± screen. The tft files that I found for the enhanced version were corrupt, and the source needs to be compiled on the LTS version of the Nextion editor. You get an out of memory error on the newest version of the editor. ?The basic version of the 2.8¡± tft file worked. ?I bought a basic version after I could not find an enhanced file version that would work. I also downgraded the editor and verified that the source for the enhanced version would compile and then loaded onto the enhanced version that I have. ?I did that when I noticed that there was an old version of the editor on the Nextion web page ?
I have not seen any benefit from the enhanced versions of the Nextion screens, so would go with cost and availability.?
FWIW, the above was my experience.?
73
Evan
AC9TU
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I would be careful with the 2.8¡± screen. The tft files that I found for the enhanced version were corrupt, and the source needs to be compiled on the LTS version of the Nextion editor. You get an out of memory error on the newest version of the editor. ?The basic version of the 2.8¡± tft file worked. ?I bought a basic version after I could not find an enhanced file version that would work. I also downgraded the editor and verified that the source for the enhanced version would compile and then loaded onto the enhanced version that I have. ?I did that when I noticed that there was an old version of the editor on the Nextion web page ?
I have not seen any benefit from the enhanced versions of the Nextion screens, so would go with cost and availability.?
FWIW, the above was my experience.?
73
Evan
AC9TU
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Re: FS: V4.3 in case, W/fan, CEC Firmware, USB cord, (Mostly) working.....
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Thanks dave. That's very useful think ihave room for the 2.8.
theres so many different screens available though. Can you recommend one?
73
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It brings a lot of menu items to the front panel. Can add noise. Have used 2.4, 2.8, 3.2 and 3.5", which was far and away better than the smaller ones. Make sure that there is enough room to fit it in. I drew a template for one.?
73
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Oop,
I missed how you connected the two radios to eachother and transmitted between them -- ouch!? Remember, the receiver section is made to amplify microvolt level signals from the antenna, but the transmitter section puts out at least 10,000 times that level.? But the fact that you were using an underpowered power supply and that you were able to send and receive signals, maybe your rigs are still OK.? Hopefully!
Listening: long wavelengths go better at night and short ones during the day, so 80m at night, 40m late evening/early moring, and 20m during the day are optimum times.? Of course closer stations can communicate with these frequencies at other times too.? You should look at the ARRL band plan (google it) to see what frequencies to listen on and for what.? But even with your short antenna, you could be able to hear CW and SSB voice pretty easily.
Do you have a radio license yet?? Studying for the tests should give you the background you will need to start really understanding and enjoying the amateur radio bands and practices/procedures.
73,
Mark
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It is a common phenomena on ubitx. Some steps to avoid this
1. Replace the mic+ PTT wire with shielded cable. Good quality usb cable can be use.
2. Keep some distance between ubitx and Linier power amplifier.
3. Give earth connection to ubitx case and pa.
This problem will solve with the 1st point itself.
If the ubitx does not come back to receiver mode after transmitting, simply replace the Rx/Tx relay with a good quality relay just like O/E/N make.
?D e VU2TDD BIJU. A. P. MARGAO, GOA
On Mon, 13 Apr 2020, 07:58 Dr M T Thomas VU3NWB, < vu3nwb@...> wrote: Thanks a lot dear Evan. Now it is?working.
On Wed, 1 Apr, 2020, 2:40 AM Evan Hand, < elhandjr@...> wrote: Dr. M T Thomas,
What you describe is a common problem with the uBiTx line of transceivers.? It is most often caused by RF getting into the rig, most likely from either the microphone cord or the coax shield. The best way to verify is to connect to an RF dummy load and see if it happens then.? If it does not stick in transmit mode, then it is RF getting back into the microcontroller.
Two solutions and both can be done.
1 - Put a common mode choke or snap-on ferrite in or on the coax from the antenna.? This is to keep RF out of the radio/shack.
2 - Put a snap-on ferrite on the microphone cord just before the plug and/or add 0.1 uF bypass capacitors on the PTT and microphone input.
Also, be sure that you have good earth ground on the case of the uBiTx.
It always helps to include the version of BiTx when asking for help on this site.? There are multiple models and versions of the BiTx radios, and the best solution can be based on which one you have the issue with.
Hope this helps.
73
Evan
AC9TU
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Thanks a lot dear Evan. Now it is?working.
On Wed, 1 Apr, 2020, 2:40 AM Evan Hand, < elhandjr@...> wrote: Dr. M T Thomas,
What you describe is a common problem with the uBiTx line of transceivers.? It is most often caused by RF getting into the rig, most likely from either the microphone cord or the coax shield. The best way to verify is to connect to an RF dummy load and see if it happens then.? If it does not stick in transmit mode, then it is RF getting back into the microcontroller.
Two solutions and both can be done.
1 - Put a common mode choke or snap-on ferrite in or on the coax from the antenna.? This is to keep RF out of the radio/shack.
2 - Put a snap-on ferrite on the microphone cord just before the plug and/or add 0.1 uF bypass capacitors on the PTT and microphone input.
Also, be sure that you have good earth ground on the case of the uBiTx.
It always helps to include the version of BiTx when asking for help on this site.? There are multiple models and versions of the BiTx radios, and the best solution can be based on which one you have the issue with.
Hope this helps.
73
Evan
AC9TU
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Re: Circuit for second PTT that will mute Mic but allow line-in...
Hi Rob,
I use an electret, a low cost Baofeng style microphone with the capsule replaced by the one supplied with the uBitx kit and larger holes in front of the capsule.
I use an SSM2167 speech compressor module between the Mic and the radio Mic input fed through a trim pot to bring the max volume to acceptable levels. See http://ubitx.net/tag/ssm2167/ for details if you are interested. It really increases the average power on SSB.
Not sure about using the bias circuit voltage.
For powering the additional circuits in my first build I added a connector on the Raduino to pickup the 5V. On my second build I simply added another 5V regulator and that's a simpler option IMO.
Hope that helps.
73, John
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thats great thankyou Evan
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On Sun, Apr 12, 2020 at 06:40 PM, Arv Evans wrote:
First time you keyed up one rig directly?
into the other you probably burned the output MOSFET devices on?
the one transmitting, but just before it blew it probably destroyed parts?
of the receiver front-end circuitry in the receive unit.
First of all I would like to say thank you for your help and reply it's really appreciated.? I really want to get my radio working! I really hope that I didn't fry anything.? During that test I was using a 12v 500ma power supply.? I'm guessing that's still enough power to destroy something?
It also indicates that your Arduino and display are?
probably still working properly.
Yes the Arduino and display still work.? The CAT control is working and when tuning the audio output definitely changes.? The uBITX Manager is working as well.
My guess is that these rigs?are repairable, but you may need lots of help?
from the experts on this group before?you have a working rig again.
That's bad news.? I'm going to mount my antenna to my car and see if things improve.? If not then I might need to call this a learning experience and order a new v6 kit.? = (
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How are you mounting the antenna?
I just have the antenna sitting on the floor.? I did not know that it grounded to the car.? Duh!? I'll go attach it to the car and see if there is any change.
How is the radio receiving other signals?? Does it sound good listening to SSB signals on 20/40/80m?
Unfortunately I'm not really sure how to do that.? I don't know what frequencies to listen on and at what times.? All I ever hear is static.
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I have not done a v3, however, the differences from a v4 are mostly in the audio, so yes you should be able to.??
Checked on Github:
There are v234 files in the archive, so yes, it should work.? Be sure to use the correct version for the screen that you will be using.
73
Evan
AC9TU
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Several ideas come to mind:
"I've assembled two uBitx v5's and was able to send and receive? ?messages on JS8Call by putting a wire directly between the two."
Whoa!? Did you read the instructions where it says to use a properly? terminated 50 ohm antenna?? First time you keyed up one rig directly? into the other you probably burned the output MOSFET devices on? the one transmitting, but just before it blew it probably destroyed parts? of the receiver front-end circuitry in the receive unit. ?Sending several? watts of RF into into the receive end of a sensitive receiver cannot be? good!
Do you have access to an SWR bridge, a dummy load, a DVM, and an? RF detector to?use with the DVM?? Normally you would not need these? but after?transmitting directly into your receiver you are probably going? to need?some test equipment and the knowledge to use it.
At this point you will have to use the schematic drawing to trace voltage? and signal levels through the circuitry.? Start with voltages, then once? they all look good you can start tracing signals in transmit mode. ? Since you can still tune the rig the Si5351 synthesizer is probably still? OK.? That is good.? It also indicates that your Arduino and display are? probably still working properly.
My guess is that these rigs?are repairable, but you may need lots of help? from the experts on this group before?you have a working rig again. ? Start by measuring DC voltages at critical points (mentally divide the? circuit into modules and check supply voltages to each module).? Make? a list of observed voltages versus where you observed them and post? it to this forum.? Others can tell you where these voltages look good? and where they look strange. ?
If you have a nearby ham who has several years of circuit repair? experience, that person may be able to provide some help and make? the repair go faster. ?
Arv ?K7HKL _._
Hello everyone.? I've assembled two uBitx v5's and was able to send and receive messages on JS8Call by putting a wire directly between the two.? I'm running the newest CEC firmware.? I also have CAT control and my audio interface is a simple USB sound card.
I purchased an antenna so I can try to receive messages in JS8Call from other hams.? The antenna is a Tram 3500 which is a CB antenna and should work fine for the 10 meter band based on my research.
I connected the shield of the antenna to the black wire, and the signal to the grey wire.? Loaded up JS8Call and nothing.? Maybe there's just nobody transmitting?
Unfortunately I don't have the second radio on hand to use for testing.
Then I disconnected the antenna and to my surprise there was no change on the waterfall.? I'm a beginner but that doesn't sound normal to me.? Here is a screenshot half of the waterfall is with the antenna plugged in and the other half is with the antenna unplugged.
I guess I have two questions.
Is there something wrong with my radio?
Are these not radio signals on the waterfall?? Is it just electrical noise?
Thanks!
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On Sun, Apr 12, 2020 at 06:03 PM, <columbustalley@...> wrote:
Tram 3500
Hi, How are you mounting the antenna?? It will need to sit on a large, flat, metal surface so the base can couple to it and provide the ground plane for the antenna (normally this is done by the car body).? If you have nothing like that, you will need to run some radial wires out from the base.? If the antenna is sitting on the ground, radial length doesn't matter, just put a bunch 4' or longer around the base.? If the antenna is elevated, then run two or more 8' long out from the base. How is the radio receiving other signals?? Does it sound good listening to SSB signals on 20/40/80m? 73, Mark
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can i fit a nextion display to a v3 ubitx ?
73 pete G4HAK
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thought this might be useful
have a ?ubitx v3 which was working great exept mic gain was v low. had a power mic DM510U handy so wired and connected it. put a 2mfd blocking cap in series with mic input line. works a treat and can control mic gain with var resistor already built into the mic. simples. and saved all those component changes!
all the best
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_Dave_ AD0B
Biju Apkrcl