No, the BFO is always below the 12mhz filter passband, if above then harmonics beat with an oscillator on the Nano.
As stated in post 44182.

Allard,

I don't think I agree with you. PBT and "clariier" are two different
things.

A "clarifer" or incremental tuning control is only useful for tuning an
off-frequency signal. The BFO must be at the suppressed carrier
frequency for proper detection of a SSB signal. If you deviate from that
frequency then the detected audio becomes distorted, the old "donald
duck" sound spoken of by the old-timers. One of my first
ham-band receivers was an old RME-4350, 1950's vintage. It had a "BFO"
control which was really useful on SSB because in a round-table not all
transmitters could be set to the exact same frequency - resolution of
1kc was pretty good! The BFO could be used to tune everyone in properly,
in essence it was what is today called an "receiver incremental tuning"
control.

Passband tuning (or IF Shift) does not impact the relationship of the
BFO to the suppressed carrier at all. You could do the IF Shift by
changing CLK1 in order to shift where the signal impacts the 12Mhz
passband of the SSB filter but CLK0 would still have to maintain the
same relationship to CLK2 in order to demodulate the signal properly.

tim ab0wr

On Sun, 11 Mar 2018 01:09:24 +0100
"Allard PE1NWL" <pe1nwl@...> wrote:

Jerry,

I believe it works in a similar way as the PBT (or "clarifier")
function in the Raduino v2 software for Bitx40.

It allows the user to slightly shift the BFO frequency from the
frontpanel (only during RX of course).
It's not IF shift in its true sense, but the behaviour is quite
similar. I have the impression that not many BitX40 builders actually
installed this mod, which has always surprised me as I personally
find it a very useful feature.

73 Allard PE1NWL

On Sun, March 11, 2018 00:52, Jerry Gaffke via Groups.Io wrote:

OK, so IF-Shift is just a BFO offset (relative to the crystal filter
passband)????
that is for receive only, the transmit BFO offset generally stays
put. Makes sense.

I went off into the weeds there because Gerald's original query
stated that

????In LSB I can adjust the received sound with the IF-Shift with a
very pleasing effect, but this does not work the same with USB.

Sounded like there was something more going on.
But could be just that the code didn't quite handle the USB case
correctly.

Yes, eventually I'll move on to try some of the newer software.
But for now have my hands full with other projects.

Jerry????????

On Sat, Mar 10, 2018 at 02:49 pm, Mike Woods wrote:

Most commercial rigs have an IF Shift or Passband Tuning (PBT)
control.????
This control can help with removal of QRM on receive ( e.g.by (
) eliminating a strong carrier or another station on
the edge
of the passband by shifting the passband up or down by a few 100
Hz. It can also compensate for a poorly adjusted frequency
response on a signal that is being received (too bassy or too
trebly).?? ????
Ian????????s software implements just such a control.???? It

functions in

a similar
manner to the BFO calibration routine, in fact, but unlike the
calibration
function, it should only operate on RX. This was the bug - it
didn????????t turn
off on TX.???? I checked on my uBITx and found the same problem here.
????
If you haven????????t tried the KD8CEC firmware you should.???? It

has a

number of
other worthwhile software features!
????

I've built 2 "Handie-Talkie" type devices.Using DOJORI DRA818V VHF Band Voice Transceiver Module V1.21- I have found them on Ebay- in single lot quantities for $11. You program them with a USB to TTL (UART) serial dongle. You can program them with CTCSS and DPL, both receive and Xmit. 1 watt output. I've run them at 3.0V (2AA's) and they tune 134-174 Mhz. There is also a UHF version- DRA818U. They will remember (powered off) 1TX freq, 1RX freq. RX or TX Tone type, RX or TX Tone Frequency, It has 8 squelch levels and 8 volume levels.. TX out is 500/1000mW
It basically looks like a 1/2 stick of gum in aluminum foil wrap. Down side.. simple 3-4 component bandpass filter needed on XMIT.. 2nd harmonic reduction is needed.
-Larry W8LM

When you read the myriad of posts on the subject of the exploding audio chip
it is easy to see a lot of the problem lies with the over-enthusiastic owner.....
not reading instructions, not understanding exactly what they are doing and the
resulting problems.

You state:
>? Does the ubitx software maintain a CLK0(USB) and a different CLK0(LSB)?

No, the BFO is always below the 12mhz filter passband, if above then harmonics beat with an oscillator on the Nano.
As stated in post 44182.

>? If not then changing the BFO (CLK0) by itself will result in an
>? asymmetric USB and LSB since the actual suppressed carrier freq now has
>? an offset.

I guess this agrees with what I was saying in post 44182, though it's not terribly clear
exactly what asymmetry or exactly what offset you are referring to.
There's a bunch of contenders here.
Yes, changing only the BFO when trying to listen to a signal is generally a bad idea.

Well, I might’ve been a bit too forceful, but I wanted people to understand that creating a product out of thin air, manufacturing and shipping it all over the world is quite an undertaking. ? If all he has struggled with are a few issues like these, the man is a magician.

I learned more in the first week on this forum than I had learned in years else where.

I’ve used the bit extra to make multiple multiple contacts even though I literally turn it on, used it to teach ham after ham Techniques because I can point to the actual components doing the jobs.

It’s in the price range of newcomers to our happy who are teenagers.

My first rig was a Heathkit HW16, which I earned by vacuuming, soldered together, and wasn’t able to get it working for almost 6 months.

I should’ve been so lucky to have a blown up component to tell me where the problem was!

On Mar 11, 2018, at 12:02, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:

From Farhan's post:?
>? just about 100 out of 4000 boards have had this problem.
>? and about less than 20 of them have reported the blow out."

So 100 boards got the WX part.
They all got turned on at HFSignals.in final test, very very few of the WX parts blew there.
It's only after they get out into the field and have a bit of operating time on them,
or perhaps see supply voltages of 14v or so, or have the speaker jack momentarily shorted,
that we see the 20 failures.? ?
HFSignals has a 2 month backlog on this product, and is scrambling to keep kits going out.
Lots of new electronics gear from established manufacturers will have these teething issues.?
Most of us have a spare LM386 or LM7805 from some older project we could patch in,
and if not they are easy enough to get.

What solution do you propose that's appropriate for a $109 kit
shipped from halfway around the world??

Jerry, KE7ER


On Sun, Mar 11, 2018 at 08:16 am, Christopher Miller wrote:

With all due respect sir, I eventually would like to purchase this kit as soon as I finish my disability claim in a month or so. This seems like a pretty serious issue. I am sure you didn't plan on parts failing but simply pointing out is only a percentage of your total production run isn't a solution.?

?

Overall from all the posts I read this kit is great. However I suspect you realized when shipping the boards with bad audio amps that it was an issue. If the original part was less than a dollar, you can easily raise the price by .50$ to 1$ us to cover the cost of putting a good part in.?

?

Thats just my .02$

?

kf4ftr

Chris?

From Farhan's post:?
>? just about 100 out of 4000 boards have had this problem.
>? and about less than 20 of them have reported the blow out."

So 100 boards got the WX part.
They all got turned on at HFSignals.in final test, very very few of the WX parts blew there.
It's only after they get out into the field and have a bit of operating time on them,
or perhaps see supply voltages of 14v or so, or have the speaker jack momentarily shorted,
that we see the 20 failures.? ?
HFSignals has a 2 month backlog on this product, and is scrambling to keep kits going out.
Lots of new electronics gear from established manufacturers will have these teething issues.?
Most of us have a spare LM386 or LM7805 from some older project we could patch in,
and if not they are easy enough to get.

What solution do you propose that's appropriate for a $109 kit
shipped from halfway around the world??

Jerry, KE7ER


On Sun, Mar 11, 2018 at 08:16 am, Christopher Miller wrote:

With all due respect sir, I eventually would like to purchase this kit as soon as I finish my disability claim in a month or so. This seems like a pretty serious issue. I am sure you didn't plan on parts failing but simply pointing out is only a percentage of your total production run isn't a solution.?

?

Overall from all the posts I read this kit is great. However I suspect you realized when shipping the boards with bad audio amps that it was an issue. If the original part was less than a dollar, you can easily raise the price by .50$ to 1$ us to cover the cost of putting a good part in.?

?

Thats just my .02$

?

kf4ftr

Chris?

Jerry,

This is a very complicated subject. The BFO, i.e. CLK0 *has* to be at
the suppressed carrier frequency in order to properly demodulate the
signal.

In order to do PBT you would have to shift three variables, CLK2, CLK0,
and the indicated frequency.

Conditions: 10Mhz suppressed carrier
CLK2 at 35Mhz to shift signal to 45Mhz
CLK1 at 33Mzh to shift signal to 12Mhz
CLK0 at 12Mhz to demodulate the signal
Freq Indicator at 10Mhz

Assume we want to shift the signal 500hz to get rid of an interfering
carrier.

Conditions: 10Mhz suppressed carrier
CLK2 at 35,000,500hz to shift signal to 45,000,500hz
CLK1 at 33Mhz to shift signal to 12,000,500hz
CLK0 at 12,000,500hz to properly demodulate the signal
Freq Indicator at 10Mhz
This would move the interfering carrier up and out of the passband.

I agree this would implement PBT or IF Shift.

This is not, however, what was being described. Moving CLK0 is truly
incremental tuning without the frequency indicator being changed. When
you move the BFO without also moving CLK2 you are changing what
frequency is considered as the suppressed carrier frequency. It will
change the relationship of all demodulated audio. If you are listening
to a CW carrier the pitch of the CW carrier will change as you change
the BFO (i.e. CLK0) by itself. This is exactly what is needed to tune
in a signal that is slightly off frequency.

Let's consider what happens if you change CLK1 and CLK0.

Conditions:
(same as original, 10Mhz Suppressed cxr,CLK2 =35Mhz, CLK1=33Mhz,
CLK0=12Mhz)

New Conditions: (move passband 500hz)
10Mhz suppressed carrier
CLK2=35Mhz to shift signal to 45Mhz
CLK1=32,999,500hz to shift signal to 12,000,500hz
CLK0=12,000,500hz to properly demodulate the signal
Frequency Indicator at 10Mhz

Same result. You can obtain PBT by changing 2 variables. You can't do
it by changing just one.

Does the ubitx software maintain a CLK0(USB) and a different CLK0(LSB)?
If not then changing the BFO (CLK0) by itself will result in an
asymmetric USB and LSB since the actual suppressed carrier freq now has
an offset.

This is what was being described.

tim ab0wr

Wow! Testy, aren't we?

I know I said basically the same thing as you. I just explained it a
little differently!

It was not meant to be a criticism of what you wrote!

tim ab0wr

On Sun, 11 Mar 2018 12:16:05 -0400
"Vince Vielhaber" <vev@...> wrote:

Did you even read what I wrote? If so, did you comprehend? You
repeated the same thing I wrote.

Vince.

On 03/11/2018 10:37 AM, Tim Gorman wrote:

Vince,

If you are listening to a CW signal then moving the IF Shift doesn't
change the tone of the CW signal at all. You are just moving the
passband. That can change the sound of a SSB signal because you are
removing some of the received audio along with the interfering
signal. Just like cutting the highs or lows with a treble/bass tone
control.

tim ab0wr

On Sat, 10 Mar 2018 21:07:17 -0500
"Vince Vielhaber" <vev@...> wrote:

IF Shift is supposed to shift the signal thru the passband without
changing the frequency. So if you're listening to 3930 and there
are signals on 3928 (it happens daily) at the same time, you can
use the IF Shift to move the signals on 3928 out of the passband.
If affects the sound of the desired signal like a tone control but
that's a side effect of the action.

Vince.



On 03/10/2018 09:02 PM, Ronald Pfeiffer via Groups.Io wrote:

Yes I was confused a while back when Ian announced his IF shift.
The code looked just like our RIT. Our RIT displays the freq on
bottom line and the line above displays the plus/minus offset as
you move the encoder.

rOn



------------------------------------------------------------------------
*From:* Tim Gorman <tgorman2@...>
*To:* [email protected]
*Sent:* Saturday, March 10, 2018 8:24 PM
*Subject:* Re: [BITX20] #uBITX Firmware KD8CEC - IF-Shift etc.

I wonder if we need to define some terms here. Passband tuning and
IF Shift typically move the *filter*, not the carrier. The carrier
will remained tuned to the same frequency when adjusting this. For
instance, if you use IF Shift when listening to a CW signal the
tone of the CW signal should not change. You can move the filter
bandwidth up or down to eliminate an interfering carrier that is
close to the desired frequency.

What you are describing is more like an Incremental Tuning, e.g.
RIT or XIT. When you move the BFO you move the carrier frequency,
not the filter bandwidth.

Ideally the BFO would be set to replicate the suppressed carrier
frequency. The filter then determines what is heard.

The ubitx uses a 12Mhz crystal filter. I don't know its bandwidth
or what the actual absolute frequencies are. I haven't had a
chance to run a spectrum analyzer against mine. Let's assume it
has a 2400hz bandwidth and goes from 12,000,300hz to 12,002,700hz.

If you want to listen to a signal at 10Mhz then CLK2 should be
tuned to 55Mhz to generate the 45Mhz signal the first IF needs.

CLK1 should then be set to generate a 12Mhz signal, i.e. 33Mhz.
For an USB signal we should then see frequencies of 12Mhz to
12.003Mhz (or whatever the transmitted bandwidth is, e.g.
0-3000hz). You will then see frequencies of 12.0003Mhz to
12.0027Mhz out of the filter.

This is how an ideal receiver would work.

When you are talking about adjusting the BFO I assume you are
talking about adjusting CLK1. If you adjust CLK1 to move the
actual suppressed carrier frequency somewhere else in the filter
bandwidth then your frequency indication is going to be off. What
should be a 10Mhz signal is going to look like something else.

This will cause an asymmetric USB and LSB response and frequency
indication.

If you want to change the BFO frequency on the fly then it should
be understood as being an incremental tuning so you can remember
what the base frequency should be.

Now each filter is probably going to have a different actual
physical, absolute bandpass. The BFO will have to be adjusted to
allow for this but the frequency indication needs to be adjusted
as well to match. It should be a fixed reference, not a variable
one.

Your transmitted frequency has to be offset from the CW-tone if it
is to be zero beat with the received signal. If it isn't then
you'll never be zero beat. I'm assuming that the CWL and CWU
frequencies are indicating a frequency CW-tone away from the
actual transmitting frequency. That may be because your receive
BFO frequency isn't set to indicate actual carrier frequency.

I didn't mean for this to get so complicated but it isn't an easy
subject.

tim ab0wr


On Sun, 11 Mar 2018 01:08:55 +0100
"ge_clipboard" <clipboard@...
<mailto:clipboard@...>> wrote:

Hi All

Many thanks for all the response concerning the BFO adjustement
and about using the IF-shift. I have been playing around with
the BFO setting while monitoring myself on another transceiver
but as I’m not getting there where I really would like to, I
returned to the factory settings. Leastening to the transmitted
LSB and USB on another transceiver was never symetric, maybe the
steps to set the bfo are not fine enough to do this or I am
making something wrong.

Yes, the IF-shift is often a very helpfull feature within crowded
bands and as Mike pointed out, it is also nice to be able to
adjust the sound of a ssb signal on receive. So, if this could be
corrected in the software would be very fine.

Another point I’ve noticed today while using CW, dx-cluster and
CAT to jump to a anounced station... When the CWL-, CWU-feature
is enabled, then the frequency is not spot on but offset by the
amount of the CW-Tone.

Nevertheless, this little rig is a joy to play with, especially
with all the added features by Ian‘s software.

Vy 73, Gerald - HB9CEY

Oh for crying out loud!

Could you folks leave this fellow alone?
He’s manufacturing A quality piece of equipment for chicken feed, under
difficult circumstances, when nobody else rose to do the job. He’s run
out of parts at least twice now when the worldwide demand for his
product exceeded the worldwide supply of quality components!

He didn’t ask component manufactures to make him inferior parts, he
simply purchase when you could find on the open market.

Once he ships it, it’s beyond the pale to ask him to find a broken ones
and replace them! All he can do his estimate the incidence, and try to
find better component manufacturers.

If any of you want gear that is warranteed, built in first world
circumstances, tested, then go pick yourself up an Icon 718 for about
$650 US.


If you’re not willing to learn a bit, work a bit, fix a bit, understand
a bit, then please get off this man’s back. It’s unfair what you’re doing.


Gordon L Gibby



On Mar 11, 2018, at 11:17, Christopher Miller <djmalak2k6@...
<mailto:djmalak2k6@...>> wrote:

With all due respect sir, I eventually would like to purchase this kit
as soon as I finish my disability claim in a month or so. This seems
like a pretty serious issue. I am sure you didn't plan on parts
failing but simply pointing out is only a percentage of your total
production run isn't a solution.

Overall from all the posts I read this kit is great. However I suspect
you realized when shipping the boards with bad audio amps that it was
an issue. If the original part was less than a dollar, you can easily
raise the price by .50$ to 1$ us to cover the cost of putting a good
part in.

Thats just my .02$

kf4ftr
Chris

You could do the IF Shift by
changing CLK1 in order to shift where the signal impacts the 12Mhz
passband of the SSB filter but CLK0 would still have to maintain the
same relationship to CLK2 in order to demodulate the signal properly.