Bob,
Thank you for reply, I verified the speaker cable and is fine, must be something else.
Alex KK4FAA

It's so much different from using audio amplifier and TV sweep vacuum
tubes in the final stages of low power transmitters. They were not
designed for that job. But they worked well (and still do). I am a fan
of those IRF510 and some others. 6BQ6, 6L6, 6AQ5, etc too.

73,

Bill KU8H


On Sat, 02 Jan 2021 14:11:29 -0800
"Jerry Gaffke via groups.io" <jgaffke@...> wrote:

Mad,

I think we're mostly on the same page here.

The uBitx is not a mil-spec radio, or anything close.
It's a rock bottom implementation of an all-band HF SSB rig,
inviting hacks to improve something, or perhaps to learn what not to
do.

I fully understand that in other arenas it matters to design by spec,
I've been there. However, there have been some excellent professional
RF engineers figuring out how to use the IRF510 for low cost amateur
builds. WA2EBY, W7ZOI, NA5N, and KB1GMX for starters.
I doubt any of them have used the IRF510 as an RF part in a product
at work, though I'm sure they all find joy in making a $0.50 part
work well as a 30mhz power amp.? Finding ways to do as much as
possible with a minimum of resources is a core part of much good
engineering.

I find it a perfect fit for the uBitx.? There are thousands of uBitx
users, I'd be surprised if more than 1% have tried moving to a
different FET. And I will speak up if somebody tries to make them
think they should.

If designing from scratch I wouldn't mess with the $2 Nano clones.
Better to just put down a modern $2 ARM QFP from Mouser.
But I haven't heard of anything better than the 40 year old IRF510
for use as a cheap RF amp.

Snowing here in far NE Oregon as well.
Forecast says we have snow on the menu for a week, temps in 20's and
30's. Have plenty to do, but this is a good excuse not to work
outside.

Jerry, KE7ER

On Sat, Jan 2, 2021 at 11:06 AM, MadRadioModder wrote:

This really is the same argument if you think about it.







The majors (Icom, Yaesu, Kenwood, etc.) don’t use a nano or
nano-clone in their radios (actually some use sister chips)… not
because of the hardware per se… but because they don’t want to
house and pay an entire army of firmware engineers on standby to
fix your meddling in their firmware. Thus its not a “open” system…
and using non-nano-like chips does aid in keeping the firmware
closed to the public and obscure. ??Most of us don’t care because
the learning curve for all of the hardware they used would be large.







Trained RF engineers will start from system specifications and
design using the most cost-effective parts.? Now, to your point, on
this one… there really are no specifications on the uBITx, other
than what is on the HFSignals website… and that isn’t much.? Maybe
Ashar just has not published them… or more likely… during the
design of the uBITx… he fiddled with parts in his basement until he
got something he liked.? No shame in that at all… witness the
number of uBITx owners.? But it is a different class of device from
one that is specified and designed from the ground up.







I won’t be mentioning the RD series of devices in this forum
again.? Takes too much of my energy for nothing.







By the way, its showing here in Wisconsin today… Great day to be on
the radio!? See you there!

-=-=-=-=-=-=-=-=-=-=-=-

Mad,

I think we're mostly on the same page here.

The uBitx is not a mil-spec radio, or anything close.
It's a rock bottom implementation of an all-band HF SSB rig,?
inviting hacks to improve something, or perhaps to learn what not to do.

I fully understand that in other arenas it matters to design by spec, I've been there.
However, there have been some excellent professional RF engineers figuring out
how to use the IRF510 for low cost amateur builds.
WA2EBY, W7ZOI, NA5N, and KB1GMX for starters.
I doubt any of them have used the IRF510 as an RF part in a product at work,
though I'm sure they all find joy in making a $0.50 part work well as a 30mhz
power amp.? Finding ways to do as much as possible with
a minimum of resources is a core part of much good engineering.
?
I find it a perfect fit for the uBitx.? There are thousands of uBitx users,
I'd be surprised if more than 1% have tried moving to a different FET.
And I will speak up if somebody tries to make them think they should.

If designing from scratch I wouldn't mess with the $2 Nano clones.
Better to just put down a modern $2 ARM QFP from Mouser.
But I haven't heard of anything better than the 40 year old IRF510
for use as a cheap RF amp.

Snowing here in far NE Oregon as well.
Forecast says we have snow on the menu for a week, temps in 20's and 30's.
Have plenty to do, but this is a good excuse not to work outside.

Jerry, KE7ER

Evan
I thank you, but which one of the 5 files do I download? HEX1.1.zip
?????????????????????????????????????????????????????????????????????????????????????? MM1.1.zip
?????????????????????????????????????????????????????????????????????????????????????? UBITX_Nextion_GUI_V3.zip
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?? UBITX_Nextion_Temp_V1.zip
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?? UBITX_TJC_GUI_V3.zip
Is it the HEX1.1.zip, just a guess!
I have also looked at videos on how to connect it up, but none that I have found tell you how to download the software.
I thank you Evan for all your help with this matter.
73

Jon?

Steady white might be wrong firmware.?
But for a flashing white screen, I'd first check current draw.
If you have a variable supply, I'd also do a slow Voltage ramp, monitor current.

Rgds,
Gary

Things to try:

Verify adequate voltage/current from your power supply. Make sure the power supply cable is firmly seated to the jack on the uBITX.

Try with the USB cable disconnected.

Reset the connectors on the Raduino (digital) board.

Reflash the Arduino program.

Replace the Arduino Nano and flash the software on it.

I hope one of these might help.

73,
Mark, N8ME

开云体育

Jon,
The prior link will get you to a zip file with the tft file that you need (at least one variant).? To transfer the tft file to the Nextion display you format a 32gb or smaller microSD card and transfer only the file that you want loaded onto it in the root directory.? Then plug the microSD card into the Nextion with the power off, Turn on the Nextion by connecting 5volts, the file should load, and give an OK.? Remove power from the Nextion. Remove the microSD card. Then verify that the home screen comes on when you apply power without the microSD card.

Anytime you want to change the Nextion screen program, just repeat the above with the new tft file loaded on the microSD card.

73
Evan
AC9TU

Evan
Bye the way if I did not tell I ordered a 2.8" Nextion .

Evan
I downloaded Xloader that's OK. But I am still confused with the Nextion firmware I still cannot find it,or I do not know what I am looking for?
Thanks
Jon

I referenced that circuitstoday.com discussion because the TDA2003 datasheet?
only had reference designs using two TDA2003's in a bridge circuit.
But it's a pretty hack job, note that they recommend an 18vdc supply when 18v is the absolute max in the datasheet.
The "AC Test Circuit" on page 4 of this datasheet might be a slightly better starting point:??
I am curious what the quiescient current would wind up being in that configuration.

Jerry, KE7ER

Most of us find that the LM386 drives a speaker adequately,
though speakers, environment, and ears can all differ significantly.

I'd start by trying out other speakers, this can make an amazing difference in volume and sound quality.
Perhaps bring some small device such as a transistor radio into a second hand store,
try driving the bookshelf stereo speakers from the headphone jack, see what works best.
Maybe even bring your old speaker into the store with you to do an A/B test.
But of course, be sure to let clerk know what you have in your pockets as you enter.

Plan B would be to make use of a small sound system of some sort that has an AUX input jack.
If you don't happen to have one, that second hand store probably does.
This would be an excellent solution if you usually use headphones anyway.

Most of the audio amp breakout boards these days are Class D, which can be much more efficient.
Class D means it is switching at perhaps 100khz or more, this can create hash in your receiver
if the board is not properly filtered and shielded.
That may work, but it is safest to stick with an old-school analog amp.? Like the LM386.

Another consideration is that most small audio amps are designed to run from one or two batteries,
so a power supply of 5 volts or less.
Easiest to have an amp that runs directly off the same 12v as the uBitx.? Like the LM386.

That said, most of those 5v class D audio amps could probably be made to work without too much trouble.

Perhaps somebody else can recommend a good 12v analog audio amp.
The TDA2003 looks promising:?
With the feedback network shown, it should have about the same gain as our LM386.

Jerry, KE7ER

Try this link for the tft files:


I have not seen a difference in performance, and had problems finding a tft file for the enhanced.? I would go with what is available, though the enhanced may give more options if you want to modify the file.

73
Evan
AC9TU

hi

i built the uBitx v6 transceiver last summer, tested it? and then put it to one side while working on other projects, Now I have come back to it and expected it to work. Unfortunately when I connect power and switch on all i Get is a screen that flashes white, and does not display the default screen. I have searched this forum for any info that might help, but nothing AFAICT.

Anyone else seen this effect? Any guidance will be useful ...

Thanks!

Evan
The site uBitx.net does not show the 2.8" screen software? So you can use the basic Nextion?? and also the Enhanced would be better??
I do know the wiring for it I found it online.
Happy New Year
Evan

I didn’t unsubscribe from any group

I found that if i plugged in the USB cable into the uBITX before turning on the volume knob the interface worked. If i had the uBITX running and then plugged in the USB there were connection errors. Something to try.

Plenty has seem to be written about audio output on the different versions of the uBitx. I was wondering if anyone out there had done a review/writeup of the different after market audio amps that are available and how to wire them up?? My audio is about good enough for headphones but I need to be able to use a speaker.

Any advice on this one greatly appreciated.? Ian K3HQL