Date   
Re: RD16HHF1 power curve flattening...some

John <passionfruit88@...>
 

Nice job Nik. Eagerly awaiting your results.

73, John (VK2ETA)

Re: Raduino oscilators. 33mhz and 57mhz " . Documentation says one thing, but this is what I measured.

Michael Shreeve
 

Hi Jerry ( and whoever else is reading) I checked my master oscillator freq , when raduino was cold, and everything else was warmed up, and found that it still says 2k high right off the bat. So, I'm working toward the possibility of calibrating my Leader Counter. I did see a blurb on from WWV where they announced that the 25.0000 signal they are transmitting is now being transmitted on a new Circularly polarized antenna. I will re-measure soon, when calibrated. I did get a lot of good info so far. Thanks for your participation. 

On Fri, Mar 9, 2018 at 10:02 AM, Michael Shreeve <shreevester@...> wrote:
Yes, 2000 is pretty much unbelievable. I'll try a couple of things,
1 measure with a scope looking at the flutter for more accuracy

2 try to check my counter using wwv ft Collins or wherever it comes from now in the same way,(possibly this should be the first step, I've put it off long enough) 

3 after I've determined a semi warm measurement where its been running continuously (I can actually measure the temp with my little orange non contact for fun, and measure the supply and 5v's just in case) , I'll turn off ONLY the uBITX and measure it in the AM . Also, I'll put a little video on for those who might want to see how I'm doing these things.

Remembering that this is a Raduino that is working quite well. This is an exercise so that I'll be VERY familiar,  for my work with an Raduino that doesn't sound so good when used..  

On Fri, Mar 9, 2018 at 9:28 AM, Michael Shreeve <shreevester@...> wrote:
Yes, I'll need to hook a scope to hear the 3 or 4 hz flutter when your spot on. Thanks Jerry. Hopefully doing more today, as its raining here finally.

On Thu, Mar 8, 2018 at 8:32 PM, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:
That's an excellent method to measure the frequency of the 25mhz oscillator.
If the receiver has sufficient low frequency audio response, you could monitor the speaker wires with a scope
and get sub hz accuracy when zero-beating.

I'll check my uBitx (tomorrow?), see how much warmup drift I can detect.
The 2.3khz drift (at 25mhz) you reported seems too large by a couple orders of magnitude. 

Jerry




On Thu, Mar 8, 2018 at 07:55 pm, Michael Shreeve wrote:
I don't know if I responded to this. I thought I explained but then maybe not. What I have always done when there is no buffered output is 1 use a receiver and an "antenna" if you will, one that is near the raduino but not touching anything. 2 turn on a somewhat stable generator and, in my case right now, measure the generator frequency directly with a counter. I can hear that generator in the same receiver.. Zero beat the generator , which is being measured, with the 25 MHz signal emanating from the raduino. Turns out it did change as I indicated, merely from heating up. No direct coupling at all for this measurement. At least to the raduino. If I had a communications monitor I wouldn't need to measure the freq of the generator. Or some other stable generator source. Also, I need to try to determine just how accurate my counter is. 
 




--
Michael Shreeve N6GRG




--
Michael Shreeve N6GRG




--
Michael Shreeve N6GRG

Re: #uBITX Firmware KD8CEC - IF-Shift etc. #ubitx

Jerry Gaffke
 

I think my first post on this thread was simply incorrect.
I don't think adjusting  SECOND_OSC_USB  would fix anything.
Unless perhaps we are somehow running up against the edges of the 45mhz filter.
But then I could be wrong, I don't really understand this one yet.

I haven't messed with your code, but do plan to.
Hope to have a full digital station going, using a RasberryPi.

And hope to take a look at your code soon and give some intelligent feedback.
For now, here's some poorly thought out unintelligent feedback:

Perhaps a temporary shift of the BFO relative to the crystal filter passband 
would be a good idea.  Allows an easy zero beat of an AM station such as WWV
when calibrating the rig, for example.  Or could be used to "clarify" the reception of some ham
with a deep voice (has mostly low audio frequencies, perhaps) who has a transmitter tuned
to match it.  Other than that, I'm not sure why any sort of temporary shift would be wanted.

How does this IF-Shift feature get used?
Exactly what does IF-Shift do?

Jerry


On Sat, Mar 10, 2018 at 01:31 pm, Ian Lee wrote:
Jerry.
 
I programmed something similar to what you said. I just added another setting instead of a constant(SECOND_OSC_USB).
 
The code is shown below.
 
    if (isUSB){
      si5351bx_setfreq(2, SECOND_OSC_USB - usbCarrier + f  + (isIFShift ? ifShiftValue : 0));
      si5351bx_setfreq(1, SECOND_OSC_USB);
    }
    else{
      si5351bx_setfreq(2, SECOND_OSC_LSB + usbCarrier + f + (isIFShift ? ifShiftValue : 0));
      si5351bx_setfreq(1, SECOND_OSC_LSB);
    }
 
Also, I would like to ask you an opinion, but now I am using the hotspot in the place where the internet is not available, so I can not use it long. 

I temporarily shifted the usbCarrier (BFO Setting value) when IF-Shift was applied.
I thought IF-Shift was a temporary function that only used for a while, so I could not satisfy both LSB and USB.
The IF-Shift value can be set to + or -, so can set the desired value according to the using mode.
 
Ian KD8CEC
 

Re: #uBITX Firmware KD8CEC - IF-Shift etc. #ubitx

Mike Woods
 

Jerry 

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!

73 Mike ZL1AXG


On Sun, 11 Mar 2018 at 11:32 AM, Jerry Gaffke via Groups.Io <jgaffke=yahoo.com@groups.io> wrote:
I think my first post on this thread was simply incorrect.
I don't think adjusting  SECOND_OSC_USB  would fix anything.
Unless perhaps we are somehow running up against the edges of the 45mhz filter.
But then I could be wrong, I don't really understand this one yet.

I haven't messed with your code, but do plan to.
Hope to have a full digital station going, using a RasberryPi.

And hope to take a look at your code soon and give some intelligent feedback.
For now, here's some poorly thought out unintelligent feedback:

Perhaps a temporary shift of the BFO relative to the crystal filter passband 
would be a good idea.  Allows an easy zero beat of an AM station such as WWV
when calibrating the rig, for example.  Or could be used to "clarify" the reception of some ham
with a deep voice (has mostly low audio frequencies, perhaps) who has a transmitter tuned
to match it.  Other than that, I'm not sure why any sort of temporary shift would be wanted.

How does this IF-Shift feature get used?
Exactly what does IF-Shift do?

Jerry


On Sat, Mar 10, 2018 at 01:31 pm, Ian Lee wrote:
Jerry.
 
I programmed something similar to what you said. I just added another setting instead of a constant(SECOND_OSC_USB).
 
The code is shown below.
 
    if (isUSB){
      si5351bx_setfreq(2, SECOND_OSC_USB - usbCarrier + f  + (isIFShift ? ifShiftValue : 0));
      si5351bx_setfreq(1, SECOND_OSC_USB);
    }
    else{
      si5351bx_setfreq(2, SECOND_OSC_LSB + usbCarrier + f + (isIFShift ? ifShiftValue : 0));
      si5351bx_setfreq(1, SECOND_OSC_LSB);
    }
 
Also, I would like to ask you an opinion, but now I am using the hotspot in the place where the internet is not available, so I can not use it long. 

I temporarily shifted the usbCarrier (BFO Setting value) when IF-Shift was applied.
I thought IF-Shift was a temporary function that only used for a while, so I could not satisfy both LSB and USB.
The IF-Shift value can be set to + or -, so can set the desired value according to the using mode.
 
Ian KD8CEC
 

Re: #uBITX Firmware KD8CEC - IF-Shift etc. #ubitx

Jerry Gaffke
 

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!
 

uBITX Firmware KD8CEC - IF-Shift etc.

ge_clipboard
 

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 TX-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

#uBITX Firmware KD8CEC - IF-Shift etc. #ubitx

ge_clipboard
 


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 


Re: #uBITX Firmware KD8CEC - IF-Shift etc. #ubitx

Allard PE1NWL
 

Jerry,

I believe it works in a similar way as the PBT (or "clarifier") function
in the Raduino v2 software for Bitx40.
https://github.com/amunters/bitx40-raduino-v2/blob/master/PBT.png
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 (
http://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!
 

Re: The issues of the TDA2822

Sajid Rahum
 

Farhan

Where can one order the good replacement TDA2822?  There are all sorts of makers but unsure where to get replacement.

My ubitx was sent 2 weeks back; most likely with the older TDA.

Thanks
Sajid/va3qy.

Re: #uBITX Firmware KD8CEC - IF-Shift etc. #ubitx

Tim Gorman
 

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@...> 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

Re: #uBITX Firmware KD8CEC - IF-Shift etc. #ubitx

W2CTX
 

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: BITX20@groups.io
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@...> 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
>





W0EB/W2CTX/N5IB RadI2Cino board is again available #ubitx

Jim Sheldon
 

Because another member chose to trash my previous post, belittling my offering to blatantly advertise his own sales offering, I reported him to the moderators for this, deleted the previous post and am reposting it again here.

I'm happy to announce that the W0EB/W2CTX/N5IB “RadI2Cino” (pronounced rad ee too CEE no) I2C replacement for the Micro BITX (uBITX) Raduino card is again available for purchase.  NOTE: these are only for the uBITX, not the BITX40 and other earlier models.

This board is designed to utilize either a 2 x 16 or 4 x 20 I2C LCD Display (not included) instead of the parallel display originally included with the uBITX so that the digital I/O lines formerly used by the display can be used to run the CW keyer and a few other functions in a much more efficient manner.

Prices have lowered a little since the first offering.

Partial kits with the IC’s soldered in place are no longer being offered.


Current options are:

1.  Bare Board (you supply the parts & you build it).  $10 US shipping included. .  International $15 US shipped.

2.  Complete Kit of Parts (less the Arduino NANO, LCD display and display I2C controller) - you build it. (All parts except the NANO, display and display controller are included in the kit.)  $30 US shipping included.   International, $45 US shipped.  All customs duties and VAT will be the responsibility of the purchaser.

3.  Completely assembled and tested RadI2Cino Including the Arduino NANO  but less the display and I2C display controller.

Assembled and tested RadI2Cino boards will be available by Special Order Only. They will require up-front payment by PayPal and up to a 1 week lead time to build and properly test)  $75, shipping included in the U.S. 

No international orders will be accepted for assembled and tested boards at this time.

All orders will receive the complete assembly manual which includes a full bill of materials, full board layout diagrams and full schematics in PDF form via email.  This manual has also been attached here as a PDF file so you can read through it and decide if it's something you'd like to build.  The same manual will be included with the order by Email.

The bill of materials listed in the manual has ordering information for the parts.  Parts suppliers are Tayda, Digi-Key and Mouser.

Please, don't post orders or info requests here as I don’t always get the posts from this reflector.

Email w0eb (at) cox dot net for ordering or further information. 

Jim Sheldon, W0EB
Park City, KS

Re: #uBITX Firmware KD8CEC - IF-Shift etc. #ubitx

Vince Vielhaber
 

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:* BITX20@groups.io
*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




Re: #uBITX Firmware KD8CEC - IF-Shift etc. #ubitx

Jim Sheldon
 

Tim the only problem I have with your explanation is on the CW offset. The transmitted CW signal MUST be exactly on the frequency shown on the LCD and the RECEIVER must be offset by the sidetone value to properly zerobeat the other signal. If you shift the transmitter frequency, when you have the other station tuned on your receiver to the same tone as your sidetone frequency, but offset your transmitter, you will be transmitting either lower or higher than his signal depending on whether you are receiving that signal in USB or LSB (CW or CWR).

Do not shift the transmitter, shift the receiver and leave the transmitted CW carrier on the display frequency if you want the offset to be proper. You might accidentally be transmitting out of band if you were tuned to a station almost on the band edge and your transmitter was offset by the sidetone value.

Ran into this problem ourselves when Ron, W2CTX and I were hashing out how CW was supposed to work a while back.

Jim Sheldon, W0EB

------ Original Message ------
From: "Tim Gorman" <tgorman2@...>
To: BITX20@groups.io
Sent: 3/10/2018 7:24:00 PM
Subject: Re: [BITX20] #uBITX Firmware KD8CEC - IF-Shift etc.



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

Re: RD16HHF1 power curve flattening...some

Glenn
 

I have been experimenting on a different tack. Imnproving the response of the PA driver stages.

I used MPSH10's in my test board build and FT37-43 toroids wound as either trifilar or bifilar according to stage needs, of 10 turns.

Comparing the original uBITX driver which has a ~7db less gain at 10M end, this version has ~2dB drop.

I don't have any spare output FETS or I would check that out also, driven by the this test board.

glenn
vk3pe

Re: RD16HHF1 power curve flattening...some

K9HZ <bill@...>
 

Glenn this is a very good idea… 

 

There are a number of ways the existing driver stages could be cleaned up. 

 

A little compensation at higher frequency should get that 2dB back.  Also I’ve implemented an electronic attenuator at the first stage (fixed parameter driven off the band selection of course) to make the gain exactly flat over the entire frequency range.   Myself, I’m interested in going up to 54 MHz but that should not be too much of a problem for that type 43 material. 

 

 

Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ

 

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

 

Owner – Operator

Villa Grand Piton – J68HZ

Soufriere, St. Lucia W.I.

Rent it: www.VillaGrandPiton.com

Like us on Facebook! facebook icon

 

Moderator – North American QRO Yahoo Group.

 

email:  bill@...

 

 

From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of Glenn
Sent: Saturday, March 10, 2018 8:26 PM
To: BITX20@groups.io
Subject: Re: [BITX20] RD16HHF1 power curve flattening...some

 

I have been experimenting on a different tack. Imnproving the response of the PA driver stages.

I used MPSH10's in my test board build and FT37-43 toroids wound as either trifilar or bifilar according to stage needs, of 10 turns.

Comparing the original uBITX driver which has a ~7db less gain at 10M end, this version has ~2dB drop.

I don't have any spare output FETS or I would check that out also, driven by the this test board.

glenn
vk3pe


Virus-free. www.avg.com

Re: RD16HHF1 power curve flattening...some

Glenn
 

Hi Bill, yes  a bit more work should get the 2dB back also. Just needs 'time'. I didn't know what spec toroids were used in the original, but had the FT37-43 on hand. The MPSH10 was on hand also, a better FT than the 2N3904's.  I did very briefly play with the bias also but  no real gains there.

Once it's all flattened out it would simplify fitting of some sort of power control immensely.

glenn

My uBitX build.

Graham W
 

Well. Got my uBitX built up and made a couple of contacts on 40 meter SSB. Good reports and
they are looking into getting them also. I am powering the radio with a 21 volt LiOn battery pack I
built.I have a CV/CC regulator built into the power supply set to 12.1 volts 2.5 amp max. All is stock in the radio.
No mods yet... Well one little one .. I added a 78L05 regulator to send 5 volts to the mic as I have placed a MAX9814
AGC board in the mic.  My heat sink is from an old marine VHF radio. Doesn't even get warm.

Here are a few pictures of the project.
Graham VE3WGW
-73-

Re: My uBitX build.

Dale Brooks KG7SSB <kg7ssb@...>
 

Nice looking rig! Good job on the build.
Dale kg7ssb

On Sat, Mar 10, 2018 at 8:37 PM, Graham W <gram.warrington@...> wrote:
Well. Got my uBitX built up and made a couple of contacts on 40 meter SSB. Good reports and
they are looking into getting them also. I am powering the radio with a 21 volt LiOn battery pack I
built.I have a CV/CC regulator built into the power supply set to 12.1 volts 2.5 amp max. All is stock in the radio.
No mods yet... Well one little one .. I added a 78L05 regulator to send 5 volts to the mic as I have placed a MAX9814
AGC board in the mic.  My heat sink is from an old marine VHF radio. Doesn't even get warm.

Here are a few pictures of the project.
Graham VE3WGW
-73-


Re: Dirt cheap uBitx case #ubitx

N1AFF - formerly KB1JPW
 

Getting there slowly. I went ahead and decided to cut new end panels. The front panel still has a few additions and different knobs to find. The rear panel has a USB port missing still.