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Radio was working fine, however I had a calibration issue so I loaded CEC and connected up MM to set it up.? After getting things set to default for calibration I reset and now I can hear faint noise in the background, but there is screeching blows everything out.? Any idea where I should start to troubleshoot this?? I only have a VOM.
Also, the screeching is consistent throughout the volume setting.
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This is audio oscillating. Check your speaker wire carefully. This can happen when the ground wires are mixed up or not connected. The speaker wire must NOT be grounded anywhere. It should go back to the board exactly as given in the wiring up instructions.
- f
On Wed, Feb 27, 2019 at 2:03 PM Hoshnasi < hoshnasi@...> wrote: Radio was working fine, however I had a calibration issue so I loaded CEC and connected up MM to set it up.? After getting things set to default for calibration I reset and now I can hear faint noise in the background, but there is screeching blows everything out.? Any idea where I should start to troubleshoot this?? I only have a VOM.
Also, the screeching is consistent throughout the volume setting.
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Hoshnasi
What is your uBITX version?? What are the symptoms when using the previous calibration values again?
What is the calibration value now? (Master Calibration, USB Calibration)
(There are differences in default calibration values depending on the version of uBITX)
1. Have you ever upload CEC firmware when uBITX is working normally??If so, do not worry. The CEC firmware saves the uBITX configuration information into backup area on the first upload to uBITX.?In this case, factory reset is available.
2.If you've ever installed a Nextion LCD to uBITX and have ever recognized the Nextion LCD's QR-Code on your cell phone,?your configuration information of uBITX is kept securely on the server.?In that case, you can use the 'Load From Server (Using internet)' button in MM to get calibration information of your uBITX from Server
3.If you upload the CEC firmware after the uBITX calibration problem, please send me your uBITX configuration file. (MM -> Connect -> Read from uBITX -> Save to File)
Ian KD8CEC
If you continue to have problems, please send me your uBITX configuration file.
(MM -> Connect -> Read from uBITX -> Save to File)
On Wed, Feb 27, 2019 at 5:34 PM Hoshnasi < hoshnasi@...> wrote: Radio was working fine, however I had a calibration issue so I loaded CEC and connected up MM to set it up.? After getting things set to default for calibration I reset and now I can hear faint noise in the background, but there is screeching blows everything out.? Any idea where I should start to troubleshoot this?? I only have a VOM.
Also, the screeching is consistent throughout the volume setting.
-- Best 73 KD8CEC / Ph.D ian lee kd8cec@...
(my blog)
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I came home tonight to the screeching gone, but now there is nothing.? Just a bit of very low noise even when connected to an antenna.
I clicked "Load Factory Setting" and the following values are set
Master: 6125
USB:?11058000
Configuration attached.?
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It looks like my radio is a V.5
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Hoshnasi
I have confirmed your uBITX settings now.?Perhaps you have done Calibration and BFO Calibration in uBITX Stock firmware. I have looked at the area that was automatically backed up (for factory reset) when the CEC Firmware was first uploaded, but the calibration value is also strange.
If it is not a hardware defect and Calibration is wrong, try the following steps.
1.Set USB Calibration value?11055700 2.Set Master Calibration value?100000 3.Click the 'Write to uBITX' button 4.Click the 'Reset uBITX' button 5.Listen to the sound. 6.Add 5000 to the Master Calibration value. 7. Goto step 3
In this way, try up to 160,000.?
Ian KD8CEC
On Thu, Feb 28, 2019 at 3:24 PM Hoshnasi < hoshnasi@...> wrote: It looks like my radio is a V.5
-- Best 73 KD8CEC / Ph.D ian lee kd8cec@...
(my blog)
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I bought a used v4 that would either screech in oscillation or was silent. The audio cable connector had to be disassembled and the connectors did not fit tight on the pins.
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I tried the new values, the screech is back and nothing else.? I can't tune to any strong station and hear the audio.
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@d balfour
The speaker wire has a strong connection.? But I'll double check it.?
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I was not as clear as I should have been. The 8 pin connector that plugs into the left side of the board. Is where the issue was that caused the feedback problem.
The problem had been solved on my radio for several months, but last night it started once again. Am going to cut off the female connector and desolder the header and solder the harness to the board.
Most problems are related to mechanical issues.
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So I swapped out my lm386 thinking that I might have blown it. Now I get ALL the am frequencies. Any ideas on what to fix next? ?Video included.?
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This is kind of beyond me now.? The radio, when turned on is receiving all the local sw stations at the same time.? All on top of each other.? I'm sure something is blown, any ideas where to start fixing this?
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Something is possibly oscillating ?and something is the demodulating most likely??; sounds like you have created a regenerative receiver!! ?Maybe add filter capacitor close to the unit between the power leads.? ?
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This is kind of beyond me now.? The radio, when turned on is receiving all the local sw stations at the same time.? All on top of each other.? I'm sure something is blown, any ideas where to start fixing this?
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On Wed, Mar 6, 2019 at 09:49 PM, Gordon Gibby wrote:
Maybe add filter capacitor close to the unit between the power leads.?
Any recommendations on the capacitor to use and exact placement?? I'll get to work on it this weekend. Thanks!
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two capacitors:
one ceramic or other cheap one, anywhere from .0047 to .1 microfarad
the other an electrolytic, anywhere from 10 uf to 100 uf
both across the power wires, as close to the board as possible.
some audio amplifier chips require such bypassing very close to the chip not to have problems......
hope this is luckily your problem....but it is just a guess
cheers,
gordon
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On Wed, Mar 6, 2019 at 09:49 PM, Gordon Gibby wrote:
Maybe add filter capacitor close to the unit between the power leads.?
Any recommendations on the capacitor to use and exact placement?? I'll get to work on it this weekend.
Thanks!
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One issue I had was that I installed the v4 version of the CEC firmware on the v5 board. That led to my low-pass switching sequencing getting all fouled up and me not hearing anything; it also messed with my BFO frequency, though it sounds like your BFO is calibrated in the right range for the v5 board. I'd also had some issues with squealing; a new nano helped, but fixing the firmware completely fixed it.
This is the version that fixed my issues:?http://www.hamskey.com/2019/02/release-cec-firmware-v1121-for-ubitx-v5.html
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YES!? That fixed it!? Wonderful!? Thanks for that info!
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Josh, Which fix worked, Gordon's or Zach's?? Terry - KB8AMZ Brimfield Twp, OH USA EN91hd Linux User# 412308, Ubuntu User# 34905,?PCARS#78, NAQCC#6668, QRP-ARCI#8855, SKCC#14195
On Sat, Mar 16, 2019 at 11:01 PM Hoshnasi < hoshnasi@...> wrote: YES!? That fixed it!? Wonderful!? Thanks for that info!
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Hosh, can you snap a pic and post it here?
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Terry & Ron,
Sorry for the late reply.? The issue was the firmware.? Zach's comment led me back to the firmware page which had been updated for my V5 board.? Once flashed, we were good to go again.
I still have some spillover from the local AM broadcast bands, but I think I'm going to try and make a filter for that.
Josh,
Josh, Which fix worked, Gordon's or Zach's?? Terry - KB8AMZ Brimfield Twp, OH USA EN91hd Linux User# 412308, Ubuntu User# 34905,?PCARS#78, NAQCC#6668, QRP-ARCI#8855, SKCC#14195
On Sat, Mar 16, 2019 at 11:01 PM Hoshnasi < hoshnasi@...> wrote: YES!? That fixed it!? Wonderful!? Thanks for that info!
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Hoshnasi
_Dave_ AD0B
Terry Morris