The news from India has been on my mind as well, check out the graph at the top:
? ? ?

As the article suggests, the US could choose to better support other nations in this.
?
Jerry, KE7ER

I see in the news that India is having a severe outbreak of Covid. Hope all is well for Ashhar and all our group members in India.

Tom, wb6b

Hi Muthu,
For issue #2, the thread to read is
/g/BITX20/message/55362
Diode isolation of those big 47uF caps?for Audio circuits from the 'RF' circuits.
(which I only recalled after a few hours of playing with my new toy scope, firmware hacks for debugging/correcting this, and looking for stored energy somewhere :)

IMO, it's not a power 'spike', it's pretty dirty RF out.
Were the spurious emissions checkers just looking at steady state, or I'm missing something??

My V6, going into TX in CW mode:? ~28ms of spurious, then things clean up.? At this time, C52 has discharged to 2.75V
The?emissions start before CW_KEY is pulled to 5V.

I haven't looked using the original firmware. (I am using Reed's)
I have not yet tried / verified the diode isolation hardware fix.? (why wasn't the hardware revised for V4+, if this the fix for this issue? )

Rgds,
Gary

Andrew,

In the video:

Go to the 10minute mark for the third step in the full calibration process (though if you did the prior steps then the frequency calibration could be off and you will have to do that part again).

Here is the BFO Tuning Aid link:

It does require a Chrome browser.? Edge or Internet Explorer does not seem to work.? You also need an antenna connected and the ?BITX tuned to an open frequency.? I have not been able to get my iPhone or iPad to work with the aid, even when I have loaded and use the Chrome browser.? It does work with all of my laptops and desktops with a mic.

The instructions on the BFO Tuning Aid page are:

• 1. Attach your hands-free to your phone or computer
• ? ? ?NOTE: This means a microphone that is connected to your computer and is allowed access by the Chrome browser.
• ?
• 2. Keep the mic an inch away from the radio’s speaker.
• ? ? ?NOTE: I have found the best results when I use a set of over-the-ear headphones connected to the phone jack on the ?BITX and the mic placed in one of the ear cups.? Adjust the volume so that the "noise plateau" appears.? Too high and the plateau is buried in all of the noise signals.? Too low and the full 2500Hz of audio is not visible.?
• ?
• 3. In the settings, choose “Setup BFO”. Tune the knob until the noise graph is centered approximately between the two red lines of 300 Hz and 3KHz
• ?
• 4. Press the encoder button again to save the settings
• ? ? ?NOTE:? Be sure to record the value of the number on the screen for future reference.? When you go back to calibrate the BFO? again it does not display the prior saved value.
• ? ? ?NOTE 2:? You do need to power the ?BITX off and then on again after pressing the tuning knob to use the saved values.

Note on the full calibration process:
There are 3 steps that form the basis for the calibration process that is described in the Ashhar Farhan video:
1 - Adjusting the BFO so that you can hear the low-frequency audio tones that are beating with the AM carrier of the known frequency AM broadcast (This can be a signal generator if you know that the generator is calibrated)
2 - Adjusting the calibration of the Master Clock in the ?BITX Raduino.? This is where you are finding the point where the audio beating just goes away.
3 - Readjusting the BFO for best speech and opposite sideband suppression.? This is centering the noise plateau to be between the two lines slightly to the right of the center.? The right edge of the plateau should be on the red 3000Hz marker line.

When doing the full calibration steps you do need to power off the ?BITX between each step.? This is to ensure that you are using the saved values from the EEPROM.? This is stated in the video.

Everything that you are describing points to first the BFO, then the mic, then the mic preamp.
73
Evan
AC9TU

Just FYI it's been sold.

Thanks,

Jeff?
KE8BLW

开云体育

(admins please let me know if this isn't allowed)

I have a uBitx v1 kit that I bought a few years ago for ~$100, I haven't had a chance to work on it so I'm putting it up for sale, $70 + $15 USPS shipping to the US or $70 for local pickup in the Capital Region of Upstate New York.

Thanks,

Jeff

--

Does anyone want my ubitxv6?? I am done.

Those spaces were designed to permit adding a cw filter in parallel.?

Curt

Are the parts in the circle missing or should they not be there?

On Sat, Apr 24, 2021 at 08:32 PM, Curt wrote:

I imagine there are numerous ubitx with fans pictured on the web - so go on a tour!?

Ahh yes, the ole just because others have done it, it must always be correct. Because people have always used parts outside their design specifications we will have to do that in all eternity.? The hobby is full with those statements .I sometimes wonder how humanity ever was been able to leave caves and evolve lol.

Jim,

I’d be interested in purchasing the Teensy 4.1 adapter kit from you. I have the uBITX v6 so it sounds like there wouldn’t be any problem with the conversion. I have the Nextion 5” Enhanced Display. Will your adapter work with this display? ?I’m not sure how to go about finding your email address, Can you provide your email address for me or explain how I would go about getting it? Thank you in advance.

73,
Robert, AG6LK?

Someone stumbled into an old thread. I am thinking this multifunction board wasn't developed, it was a collection of ubitx add on. Not sure it cured v3 v4 spurious (-:? it even was going to host my favorite simple audio agc. Maybe it was mentioned about same time or after the jackal. In earlier ubitx stages many third parties were making various boards small and big. Seems this all waned with v5 and v6 where displays have had a larger focus.?

Curt

I imagine there are numerous ubitx with fans pictured on the web - so go on a tour!? Thermal science of transistors is a bit abstract even working with PhDs I work with - so stay with your conviction on how much air you want to move.? I haven't yet down FT8 with my ubitx - but it tends to be shoot with what you have mode - I imagine big stations may be running hundreds of watts - but certainly QSOs can be had with a stock ubitx.? The fans in my switching power supply scream a bit - possibly you might want a switch to turn it off when doing CW and SSB - your call its your custom ubitx.?

73 Curt

What board is this?

Gerry. VE4GKS

Sent by the Thunderbird