Re: Highlighting band selected

#79371

Jeff

The BITX20 discussion group is a community of people with like interests?

and experiences.? Some are casual?users of the equipment, and most are?

licensed ham radio operators who have technical talents as evidenced by?

their passing the ham radio exams.? The uBITX, and BITXxx, before uBITX?

were designed for the Ham radio community.? Most of the members of this?

discussion group are here to discuss mods, operating, and camaraderie.

As of today there are 7871 members of the group, most of which are?

satisfied with their uBITX, BITX40, or earlier BITX20 units.? BITX units?

have evolved over time, usually involving on-line discussions and suggestions.

The people on this group are willing to help with problems, but that requires?

working with these helpers.? If one just powers up a new uBITX and starts?

pushing buttons without understanding what it might do, then problems may

occur.? If you look at the block diagram, and then at the schematic, you will?

see that the uBITX is not a simple circuit.? It is the result of several years of?

design, testing, re-design, and more testing by those with experience in?

this work.

uBITX boards are "factory tested" before they are shipped.? It is unlikely?

that a defective uBITX board was overlooked and shipped without testing.??

The tests performed at HFSignals have been listed earlier on this group.??

The tests performed could be listed again but probably would not mean?

much unless the owner takes the effort to understand how the radio works.

Now, some "remote guessing" at what might be the problem.??

Others have suggested that the BFO adjustment could be off.?
That is the most likely problem...and could have been reset by
yourself when initially trying to operate the rig.? We do need?
you to perform the BFO alignment procedures before we go?
further.? To do this you need to understand the concepts of?
"zero-beat" and "offset".? Picture the IF filter as an open door
that allows only passband frequency signals to go through.
Unless the incoming signal mixing with the tuning oscillator?
is heterodyned to inside the filter passband, you will not be
receiving the desired signals.? Once the desired signal is??
passing through the IF filter, it is again heterodyned to audio
by mixing that signal with the BFO.?

On transmit this?process is reversed with audio plus BFO
(balanced for Suppressed Carrier DSB generation) and
presented to the?IF filter which slices off the sideband that
falls outside the?filter passband.? Note that if your BFO is
misaligned so?that both sideband?fall inside the filter
passband, you will?be transmitting both sidebands, or what
is known as Suppressed Carrier AM.
The next but unlikely possibility is that one of the balanced
demodulator diodes was installed backwards at the factory.
We can test for that if you are willing, but first we need to?
know that the BFO is adjusted properly.? Without that any?
tests might be counter-productive.
Highly unlikely?is that the IF transformer feeding the detector?
has been mis-wired or mis-connected at the factory.? This?
would have been caught at testing time, but we will not rule?
it out as a last resort.??
Least possible possibility is that your crystal filter is not filtering?
properly.? That would have been caught during factory testing.

And, please remember that the members of this group who volunteer?

their time to help you with your uBITX are not employees of HFSignals?

and do not get paid for their time.? The BITX phenomena started as?

an idea on an aircraft flight between New York and India.? It was initially?

built by individuals from junkbox parts.? Then one ham started offering?

bags of parts (no PCB) for building your own BITX transceiver.? And,?

the rest is history.? Group support is rather unique among manufacturing?

of technical products, but is not unheard of.? It has worked well for the?

uBITX and for the group.

Yes, a long email, but it may help to understand the idea of Group support?

and of the uBITX itself.

Arv? K7HKL

_._

Show quoted text

On Thu, May 28, 2020 at 8:57 AM Jeff Debes <jeff.debes@...> wrote:

Bill, Tony,

Thanks for the advice.
To be clear: I have a confirmed QSO where the op copied me on LSB and USB with out me changing any settings.
?Is that still a possible symptom for misaligned BFO?
If so fine. I will try again at home with a PC.
I want to say that the kit is sold as a working board, &? the buyer is trusting that it is working, that it was tested properly. What if it is not? That will happen.
Documentation clarity for engineers is one matter, and appears to be simple enough, for casual builders it may need to differ.
A support group such as this is fine for resolving many issues , but it should not be the only recourse.
Why do so many users come back here to ask questions? ( the documentation is not adequate?)
Personally, I’m used to building non-digital circuits/radios.? ?There is operability simplicity , excellent ease of use,? and clarity in analog radio circuits.
Anyway
Thanks everyone for the advice. I will try the suggestions.

Jeff
> On May 28, 2020, at 9:25 AM, Bill Cromwell <wrcromwell@...> wrote:
>
> ?Hi,
>
> I have to agree with Tony and the others on this. A misaligned BFO will produce the same symptoms on *ANY* radio like this one (includeing those with four figure price tags). I have worked on a few for other hams and the BFO way way far off on the ones with these symptoms.
>
> If you are unable to get it working you might find somebody on here to get it going for you. I think you should try to get it working yourself. I did not find any deficiencies in the instructions.
>
> 73,
>
> Bill? KU8H
>
>> On 5/28/20 8:27 AM, Tony Vandenborn wrote:
>> Jeff
>> When you study the uBITX block diagram, and understand it, you can clearly see it is rather impossible that your radio receives/transmits both sidebands same time. You really have to align the BFO and master oscillator frequencies, your kit is not defective!
>> Tony
>> Op do 28 mei 2020 om 14:18 schreef Jeff Debes <jeff.debes@... <mailto:jeff.debes@...>>:
>>? ? Ok Stephen,
>>? ? I will think about trying it.
>>? ? I used to do a small bit or arduino programming but that is not
>>? ? something i want to get back into.
>>? ? Right now though I need to know why my radio only works as double
>>? ? sideband. I don’t think its an alignment problem,? I? have doubts
>>? ? that tuning will cure the issue.
>>? ? I hope someone has ideas on what might be wrong else I might want to
>>? ? return this unit to HD Sigs as defective.
>>? ? Jeff
>>>? ? On May 28, 2020, at 7:28 AM, Stephen KO4CVU
>>>? ? <goinfishin1952@... <mailto:goinfishin1952@...>> wrote:
>>>
>>>? ? ?Jeff, I can vouch for Reed’s software. It makes a great
>>>? ? improvement in the operation and control of the touchscreen.
>>>? ? Downloading and installing It was my first experience working with
>>>? ? an Arduino Nano, (although I did have some experience with
>>>? ? programmable logic controllers years ago.) If I can do it, it must
>>>? ? not be too hard! :) I will be happy to share my notes about the
>>>? ? process with you, if you’d like them.
>>? ? --? ? ?*jeff.debes@... <mailto:jeff.debes@...>*
>
> --
> bark less - wag more
>
>
>

--
*jeff.debes@...*

Re: Turn of BFO mod

#79370

Jeff,

No, no and no.

Reasons the filter is less than 2.5Khz wide so even with a diode detector it would
sound really muddy.? AM really wants AGC, no got.? ?FM wants a wider filter as
well though its mostly a 10M thing.

Or you can tune in the AM and zero beat the carrier and listen to AM.
The digital VFO is stable enough to stay within a few HZ for days.

Allison
---------------------------------
No direct email, it goes to bit bucket due address harvesting in groups.IO

Re: New V6 CW tone frequency

#79369

I would recommend that all check calibration, as there have been a lot of reports of issues.? None of the 3 boards that I bought were calibrated accurately from the factory.?

Ashhar Farhan has made it fairly simple for the version 6 boards.? The video instructions are here:

with the BFO tuning aid here:

The above should be done as the first step in solving sensitivity, power, transmission distortion, or selectivity issues.? The basic steps are the same for all boards, the details of how to get to the calibration and for the version 5 board the fact that stock software transmits a 10 MHz carrier for the calibration.? The BFO adjustment is the same.
73
Evan
AC9TU

Re: New V6 CW tone frequency

Dale Parfitt

#79368

开云体育

It certainly sounds as though you need to calibrate? the BFO.? As is signals, are on the edge of the crystal filter.

When mine arrived sidebands were reversed. Calibrating the BFO fixed it instantly.

?

Dale W4OP

?

Show quoted text

From: [email protected] [mailto:[email protected]] On Behalf Of rskarka@...
Sent: Thursday, May 28, 2020 7:06 AM
To: [email protected]; robert.skarka@...
Subject: [BITX20] New V6 CW tone frequency

?

Yesterday I received my new uBITX v6 full kit and assembled it. After a short function check (could hear some CW and FT8 signals), I installed CEC firmware and Nextion display. Everything worked right out of the box, but later I noticed, that when I tune to CW signals, the audio tone is very high. When I tune the HF for strongest audio signal, the audio tone is around 5khz, and when I change the frequency to get the tone lower, the signal disappears before getting down to the range of 1kHz.

For testing, I tuned to a strong CW station in LSB, USB, CWL and CWU. The highest volume for each mode was approximately:

?

7029 kHz LSB

7033 kHz CWL

7023 kHz CWU

7025 kHz USB

?

With SSB modes I can tune the tone frequency down, but also the signal is stronger at higher frequencies than 800Hz

?

So far, I didn't do any calibration, and right after uploading the CEC firmware, I downloaded the eeprom data with the ubitx manager software.

Could this be a frequency or bfo calibration issue? Im not sure, because it is mostly a problem in CW modes, and I thought the boards come calibrated from the factory.

?

Should I go back to the stock fw and display to run the calibration procedure of the V6 firmware with the web spectrum analyzer tool?

?

Something else to check? I have an HP/Agilent Oscilloscope, but the last calibration of that was 2003, so not sure how accurate the frequency counter of that is.

?

Thanks for help,

?

Robert

Re: Highlighting band selected

#79367

Jeff

Until?you have tried the alignment procedure there is no way we can know?

if you have a real problem, or if you just have not performed the alignment?

process.? We would like to help you, but you have to work with us.? What?

have you tried thus far?? What were the results of performing the alignment?

process?

Arv

_._

Show quoted text

On Thu, May 28, 2020 at 6:18 AM Jeff Debes <jeff.debes@...> wrote:

Ok Stephen,
I will think about trying it.
I used to do a small bit or arduino programming but that is not something i want to get back into.
Right now though I need to know why my radio only works as double sideband. I don’t think its an alignment problem, ?I ?have doubts that tuning will cure the issue. ?
I hope someone has ideas on what might be wrong else I might want to return this unit to HD Sigs as defective.
Jeff

On May 28, 2020, at 7:28 AM, Stephen KO4CVU <goinfishin1952@...> wrote:

?Jeff, I can vouch for Reed’s software. It makes a great improvement in the operation and control of the touchscreen. Downloading and installing It was my first experience working with an Arduino Nano, (although I did have some experience with programmable logic controllers years ago.) If I can do it, it must not be too hard! :) I will be happy to share my notes about the process with you, if you’d like them.

--
jeff.debes@...

Re: Both sidebands present on receive or transmit? V6

#79366

Jeff

Have you tried to do the necessary adjustments???

Arv

_._

Show quoted text

On Thu, May 28, 2020 at 5:28 AM Jeff Debes <jeff.debes@...> wrote:

It really seems that this radio is? working as double sideband? transmit and receive.
Not sure that adjustments will
fix this.

--
*jeff.debes@...*

Re: Turn of BFO mod

#79365

Jeff

This is an SSB radio.? It requires the BFO to heterodyne the IF frequency to audio.

It might be possible to convert it to an AM radio by building a non-SSB detector to?

connect ahead of the heterodyne style detector circuit.? Why stop at AM?? Might?

also be interesting to add an FM style IF section and FM detector!

Another possibility is something like the rather old "Q-5'er" which would be an AM?

receiver tuned to the IF frequency and connected ahead of the SSB detector.
This might work, or might be plagued?with BFO leak-through, unless the BFO were?

set way off the IF frequency or even turned off for AM mode.

All desires?for the SSB transceiver to do something that it was not designed to do?

may be possible, and many on this group have dome some of these mods.? What?

is required to successfully modify the original circuit and original software is a good?

knowledge of how the system actually works, and how to design suitable?

modifications.

Arv

_._

Show quoted text

On Thu, May 28, 2020 at 5:28 AM Jeff Debes <jeff.debes@...> wrote:

Is there a way/mod? to turn off the bfo to listen to AM signals?

--
*jeff.debes@...*

Re: UK Import Charges

howard winwood G4GPF

#79364

开云体育

they are! but not exempt to vat. vat goes on postage too.

Show quoted text

On 28 May 2020, at 16:10, Mark G?NMY <mark.g0nmy@...> wrote:

I always thought Amateur radio parts were exempt form import duty??
?

New V6 CW tone frequency

[email protected]

#79363

Yesterday I received my new uBITX v6 full kit and assembled it. After a short function check (could hear some CW and FT8 signals), I installed CEC firmware and Nextion display. Everything worked right out of the box, but later I noticed, that when I tune to CW signals, the audio tone is very high. When I tune the HF for strongest audio signal, the audio tone is around 5khz, and when I change the frequency to get the tone lower, the signal disappears before getting down to the range of 1kHz.

For testing, I tuned to a strong CW station in LSB, USB, CWL and CWU. The highest volume for each mode was approximately:

7029 kHz LSB

7033 kHz CWL

7023 kHz CWU

7025 kHz USB

With SSB modes I can tune the tone frequency down, but also the signal is stronger at higher frequencies than 800Hz.

So far, I didn't do any calibration, and right after uploading the CEC firmware, I downloaded the eeprom data with the ubitx manager software.

Could this be a frequency or bfo calibration issue? Im not sure, because it is mostly a problem in CW modes, and I thought the boards come calibrated from the factory.

Should I go back to the stock fw and display to run the calibration procedure of the V6 firmware with the web spectrum analyzer tool?

Something else to check? I have an HP/Agilent Oscilloscope, but the last calibration of that was 2003, so not sure how accurate the frequency counter of that is.

Thanks for help,

Robert

Re: Bitx V6 Modifications

[email protected]

#79362

开云体育

Stephen

Thanks for your reply. What microphone with pre-amp would you recommend??

Jody

Show quoted text

On May 28, 2020, at 12:57 PM, Stephen KO4CVU <goinfishin1952@...> wrote:

?First, read the “uBITX Power and Gain Issues” topic in the Wiki for more information. Don’t expect the same power output on 10 meters as you might get on 80 meters.
Second, go ahead NOW and order a microphone with a pre-amp if you intend to communicate via phone/SSB. You will also need a stereo plug to install on the new microphone cord, if you buy one.
Third, after turning on the unit and familiarizing yourself with the factory Arduino sketch, download and install Reed’s latest sketch. You will really appreciate his improvements.
Fourth, spend a LOT of time watching Arhhan’s video about how to adjust the VFO and BFO. You may need to check these adjustments on the radio you receive. It has taken me a number of adjustment attempts to get close to usable settings.

Re: Not getting daily digests

#79361

Yes mine and a local friend noticed the same thing , no overnight digests since about a week ago.?
I was able to get it back when I switched to full featured digest.
--
73
Dave

Re: Turn of BFO mod

#79360

Maybe a diode detector (like an RF probe) between CW-1 pin 1 and TP 20 might work to receive.? The selectivity is then defined by the 45 MHz roofing filter, which is 15 kHz wide.? You would need to turn off the BFO.? It would require a switching circuit for the diode to be able to back to SSB/CW with the crystal filter.

Just speculation on my part.

73
Evan
AC9TU

Re: Turn of BFO mod

#79359

Jeff

we get the framework of your question - its in relation to BFO action on 'ancient' typically general conversion receivers, that lacked a proper product detector.?

an AM signal off course is 2X or more wider than SSB, especially if we want more spectrum into our headphones.? the 2nd xtal filter is too narrow for AM signals - for both sidebands to pass through.? but some may have added a product detector after the first 45 MHz xtal filter.? try a search engine to see who has reported results adding an envelope detector -- uBITX envelope detector or AM detection.? BTW, an envelope detector is pretty much a simple diode - but it has to have appropriate gain in front of it (but it might not take much for huge 41m AM signals.? others add a SDR at 45 MHz that would also be a good AM receiver.?

I appreciate your inquisitiveness.? Too easy for us to miss context of your question, not presuming product detector behavior.

73 curt

Re: Turn of BFO mod

#79358

I described how to skip the BFO stage, but didn't put any thought into if it would actually work for AM. It may actually be that the audio mixing stage ended up becoming the BFO, sans filter, or perhaps there would be no output at all, like you speculate.

Reed

Re: Not getting daily digests

#79357

I'd try checking if they somehow ended up in Spam. Sometimes that happens to me with just random subscription emails like YouTube.

Cheers,

Marko

Show quoted text

On Thu, 28 May 2020, 8:01 PM AG?H <[email protected]> wrote:

I haven't been getting the 'daily digest' from this group for over a week.? I've gone into my subscription settings and found nothing has changed:? the daily digest option is still checked.? I rechecked it again and hit the 'save' button.??
Unfortunately, nothing has changed.??
How do I 're-activate' it?
Keith-AG?H

Re: Turn of BFO mod

Dale Parfitt

#79356

开云体育

Hi Reed,

I cannot see how a signal ?will be present at the output of the product detector if you remove the BFO signal. Isn’t that equivalent to multiplying by zero (0)? And then any residual that ?does remain (extremely low level) would require an envelope detector for AM demod.

?

Dale W4OP

?

Show quoted text

From: [email protected] [mailto:[email protected]] On Behalf Of Jeff Debes
Sent: Thursday, May 28, 2020 1:52 PM
To: [email protected]
Subject: Re: [BITX20] Turn of BFO mod

?

Thank you Reed , you’re always very helpful!

On May 28, 2020, at 12:14 PM, Reed N <greenkid336600+groupsio@...> wrote:

?
You should be able to listen to AM even with the BFO. However, if you want to get rid of it completely for some reason, you'll need to jumper C211 to C40 to remove the BFO crystal filter stage, then modify the code to get the correct mixing products on the audio side. I don't think I'd recommend this.

Reed

--
jeff.debes@...

Not getting daily digests

#79355

I haven't been getting the 'daily digest' from this group for over a week.? I've gone into my subscription settings and found nothing has changed:? the daily digest option is still checked.? I rechecked it again and hit the 'save' button.??
Unfortunately, nothing has changed.??
How do I 're-activate' it?
Keith-AG?H

Re: uBitX assembled: bit of a challenge with alignment/bfo adj - Volume/switch knob fix

Jeff Debes

#79354

开云体育

Great explanation Arv!?

Thanks!

Show quoted text

On May 28, 2020, at 1:55 PM, Arv Evans <arvid.evans@...> wrote:

?
Dan

It seems that a number of new users of uBITX are not familiar with the "zero-beat"?
process, and not familiar with BFO offset relative to crystal filter bandwidth.??

If doing?a zero-beat and your BFO is not properly aligned then the received signal?
will not be placed properly inside the filter passband.? This Allows the opposite?
sideband to be heard over top of the zero-beat.??

Technical info..... When setting the BFO frequency relative to received frequency,?
the BFO should be set approximately 12 db down one side of the crystal filter?
skirt.? Which skirt is determined by which sideband is going through the filter.
You have a DSB signal prior to the filter and setting the BFO 12 db down the?
filter skirt further reduces the unwanted sideband.? Doing this also rolls-off low
frequency audio tones to make your sideband signal more efficient.
The uBITX assembly instructions do include a block diagram that should make?
this easier to understand.??

Arv
_._

On Wed, May 27, 2020 at 10:14 PM <pulco.ant@...> wrote:
Hello. Got my full kit (board v6.2 / firmware v6.1) the other day and assembled it this morning.Easy as pie.

I managed to puzzle out (I think) how to get into alignment: hold tuning knob in while powering up. The screen calibrate _everytime_ is annoying. Zerobeating is challenging because there is a second hetrodyne that becomes audible and climbs in frequency *just* as I'm approaching zerobeat. So far, when I tune WWV afterwards, the display read 10,000.05, and I've done it a number of times. Setting the BFO - what's that about? I used an audio spectrum analyzer as 1 post suggested, but - is that all there is to it?

Volume/switch knob: I dealt with that by grinding down about 3/32" of the knob from the radio side of the knob. This allows that setscrew to move further down the switch shaft and it gets much better purchase on the shaft.It just doesn't have the same flare now as the tuning knob.

Please ring in with suggestions.

Thanks and 73
--
Dan D'Eon
AG7GM

--
jeff.debes@...

Re: Bitx V6 Modifications

#79353

First, read the “uBITX Power and Gain Issues” topic in the Wiki for more information. Don’t expect the same power output on 10 meters as you might get on 80 meters.
Second, go ahead NOW and order a microphone with a pre-amp if you intend to communicate via phone/SSB. You will also need a stereo plug to install on the new microphone cord, if you buy one.
Third, after turning on the unit and familiarizing yourself with the factory Arduino sketch, download and install Reed’s latest sketch. You will really appreciate his improvements.
Fourth, spend a LOT of time watching Arhhan’s video about how to adjust the VFO and BFO. You may need to check these adjustments on the radio you receive. It has taken me a number of adjustment attempts to get close to usable settings.

Re: uBitX assembled: bit of a challenge with alignment/bfo adj - Volume/switch knob fix

#79352

Dan

It seems that a number of new users of uBITX are not familiar with the "zero-beat"?

process, and not familiar with BFO offset relative to crystal filter bandwidth.??

If doing?a zero-beat and your BFO is not properly aligned then the received signal?

will not be placed properly inside the filter passband.? This Allows the opposite?

sideband to be heard over top of the zero-beat.??

Technical info..... When setting the BFO frequency relative to received frequency,?

the BFO should be set approximately 12 db down one side of the crystal filter?

skirt.? Which skirt is determined by which sideband is going through the filter.

You have a DSB signal prior to the filter and setting the BFO 12 db down the?

filter skirt further reduces the unwanted sideband.? Doing this also rolls-off low

frequency audio tones to make your sideband signal more efficient.

The uBITX assembly instructions do include a block diagram that should make?

this easier to understand.??

Arv

_._

Show quoted text

On Wed, May 27, 2020 at 10:14 PM <pulco.ant@...> wrote:

Hello. Got my full kit (board v6.2 / firmware v6.1) the other day and assembled it this morning.Easy as pie.

I managed to puzzle out (I think) how to get into alignment: hold tuning knob in while powering up. The screen calibrate _everytime_ is annoying. Zerobeating is challenging because there is a second hetrodyne that becomes audible and climbs in frequency *just* as I'm approaching zerobeat. So far, when I tune WWV afterwards, the display read 10,000.05, and I've done it a number of times. Setting the BFO - what's that about? I used an audio spectrum analyzer as 1 post suggested, but - is that all there is to it?

Volume/switch knob: I dealt with that by grinding down about 3/32" of the knob from the radio side of the knob. This allows that setscrew to move further down the switch shaft and it gets much better purchase on the shaft.It just doesn't have the same flare now as the tuning knob.

Please ring in with suggestions.

Thanks and 73
--
Dan D'Eon
AG7GM