Re: Spurs/Harmonics fixes for v4 based on v5 board design?

#64193

Personally, I am happy to see the SA, etc., discussions.

While I am not into doing this, it does make me stop and
think and I'm learning some things in the process. Also,
here and there are some side comments that have given
me some other interesting data to absorb and I appreciate
it. This is just my opinion, though. Use it as you willl.

Bob — KK5R

--------------------------------------------

Show quoted text

On Mon, 1/21/19, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:

 Subject: Re: [BITX20] Spurs/Harmonics fixes for v4 based on v5 board design?
 To: [email protected]
 Date: Monday, January 21, 2019, 2:06 PM

 Given the issues with
 spurs and harmonics, any talk of cheap ways 
 to do an SA?seems entirely appropriate here.?

 Perhaps some would prefer not to think
 about it?

 A long winded
 discussion about a Bitx20 will raise objections here
 from a few of those who think it should be all
 about their uBitx.
 And hey, don't be
 talking about that software stuff!

 The HBTE SA discussion was mostly about
 stringing together a bunch 
 of ebay modules
 to create an SA.
 The RTL-SDR's can be
 had on ebay, and require a bunch of other things
 strung in there with it to be a functional
 SA.? I don't see much difference.

 I'm happy to discuss this further either
 here or on HBTE.

 /rant

 > Since I
 now see objections to this thread from Mars I am out of
 it.

 Very cool!
 Who do you know from Mars?

 Jerry, KE7ER

 On Mon, Jan 21, 2019 at 10:40
 AM, Bill Cromwell wrote:

 The HB in HBTE is for home brew. RTL-SDR and
 those other gadgets are not home brew. It's doubtful
 they belong there either. Maybe there is an RTL-SDR group
 somewhere.

 Since I now see
 objections to this thread from Mars I am out of
 it.

Re: Good mic for Ubitx and Bitx40

Denis

#64192

开云体育

I have had good audio reports using my Icom 7300 mic with the BITX40.

Denis, WB8SKP

On 1/21/2019 10:45 AM, Daimon Tilley wrote:

Show quoted text

I use one with my Yaesu FT891 and it seems fine. Not tried it with the ubitx though.

On 21 Jan 2019, at 16:30, twowindsbear via Groups.Io <twowindsbear@...> wrote:

Check? this out!

I have no clue how well this microphone would work for the uBITX & such, but for <$30.00 it SURE looks impressive!

Re: Spurs/Harmonics fixes for v4 based on v5 board design?

#64191

Thanks!

Show quoted text

On Mon, Jan 21, 2019 at 12:18 PM, Allen Hill wrote:

Hi guys, I've owned an RF Explorer for a couple of years now. It's not a Rigol, etc. But is an extremely useful instrument. The guts is a SILABS transceiver and a PIC controller. See the original website here, http://j3.rf-explorer.com.? Loads of info, you can drill down and get access to schematics and code.

I've used it for many radio and OTA TV measurements with great success. It's easily automated with Python SW (I've done it).

There are limitations, some mentioned on a thread in the HBTE forum. Let me know if you have particular questions and I'll try to answer them.

Thanks!

Allen Hill, KI4QCK

Re: New ubitx CW not transmitting

#64190

Steve,

BINGO!? That fixed it.? Glad it was an ID-10-T error (software developer code name for "idiot" users) and not a hardware problem.?

Is there a good PDF user manual for us newbies?

Many thanks!

Allen KC8VRI

Re: Spurs/Harmonics fixes for v4 based on v5 board design?

#64189

Hi guys, I've owned an RF Explorer for a couple of years now. It's not a Rigol, etc. But is an extremely useful instrument. The guts is a SILABS transceiver and a PIC controller. See the original website here, http://j3.rf-explorer.com.? Loads of info, you can drill down and get access to schematics and code.

I've used it for many radio and OTA TV measurements with great success. It's easily automated with Python SW (I've done it).

There are limitations, some mentioned on a thread in the HBTE forum. Let me know if you have particular questions and I'll try to answer them.

Thanks!

Allen Hill, KI4QCK

Show quoted text

On January 21, 2019, at 2:21 PM, Evan Hand <elhandjr@...> wrote:

My thoughts are that as long as the cost fits in the cool toy range for your budget, then the RF Explorer is a reasonable way to learn about spectrum analysis without going in to the $700 plus toy range (some peoples toy budget are greater than mine:).? The advantage of even a low accuracy device like the RF Explorer you can have a reasonable expectation that it works.? There is less of a chance of an error in construction, and recourse to the supplier if there is an issue.? I know that I have learned a lot about SAs through the process, as well as RF measurements in general.? I know with some certainty that the weird results were more likely my process error, as opposed to the device not working.? If this would have been a kit I would have been looking for the construction error, instead of the operator error.

To my way of thinking, there is a spectrum (no pun intended) of probability of working out of the box, with for me the low end being the kit and the high end the certified test equipment.? With that you couple in the possibility of damage due to overload (I am still getting my head around attenuators and how to connect them to the uBitx) that I would be concerned that I burn out the higher priced device.

I do know that I will be purchasing either a Rigol or Siglent SA in the future.? ?I am just not ready to do so until I know more.?

A topic on how to connect or test the uBitx for spurs and harmonics would be a good topic for this group.? At this stage I can share how I used the RF Explorer to verify the 3rd order harmonic from 7.01 (there is code to prevent CW from working at 7.000mhz that I found out after a gut wrenching "OH NO" when I thought I blew the finals).? That would include the first ugly dummy load to the way that I created an attenuator out of a dummy load, rf tee connector and a piece of wire sticking out of the tee.? This would not be needed if there was a way documented on how to reduce and then restore the power out of the uBitx and yes I know that R1 can do this, just not sure how to set it back again at a point where I will not blow the finals on the lower bands.

Lots of possibilities, if only I were retired (again).

73
Evan
AC9TU

Re: New ubitx CW not transmitting

#64188

In the settings menu, you will find the default keying mode is set to use an iambic keying paddle. Change that setting to use a hand key.

73, Steve, N3SB

On Jan 21, 2019 3:11 PM, "Bob Hart" <bjh141@...> wrote:

Show quoted text

I Have the same problem with exactly the same symptoms.? ADC values go from 1023 to 0 when I press the key but ubitx does not go into transmit (no relay clicks). Software version 4.3.? Will have to check the source code to see what is happening.

Re: New ubitx CW not transmitting

#64187

I Have the same problem with exactly the same symptoms.? ADC values go from 1023 to 0 when I press the key but ubitx does not go into transmit (no relay clicks). Software version 4.3.? Will have to check the source code to see what is happening.

Re: Spurs/Harmonics fixes for v4 based on v5 board design?

#64186

My thoughts are that as long as the cost fits in the cool toy range for your budget, then the RF Explorer is a reasonable way to learn about spectrum analysis without going in to the $700 plus toy range (some peoples toy budget are greater than mine:).? The advantage of even a low accuracy device like the RF Explorer you can have a reasonable expectation that it works.? There is less of a chance of an error in construction, and recourse to the supplier if there is an issue.? I know that I have learned a lot about SAs through the process, as well as RF measurements in general.? I know with some certainty that the weird results were more likely my process error, as opposed to the device not working.? If this would have been a kit I would have been looking for the construction error, instead of the operator error.

To my way of thinking, there is a spectrum (no pun intended) of probability of working out of the box, with for me the low end being the kit and the high end the certified test equipment.? With that you couple in the possibility of damage due to overload (I am still getting my head around attenuators and how to connect them to the uBitx) that I would be concerned that I burn out the higher priced device.

I do know that I will be purchasing either a Rigol or Siglent SA in the future.? ?I am just not ready to do so until I know more.?

A topic on how to connect or test the uBitx for spurs and harmonics would be a good topic for this group.? At this stage I can share how I used the RF Explorer to verify the 3rd order harmonic from 7.01 (there is code to prevent CW from working at 7.000mhz that I found out after a gut wrenching "OH NO" when I thought I blew the finals).? That would include the first ugly dummy load to the way that I created an attenuator out of a dummy load, rf tee connector and a piece of wire sticking out of the tee.? This would not be needed if there was a way documented on how to reduce and then restore the power out of the uBitx and yes I know that R1 can do this, just not sure how to set it back again at a point where I will not blow the finals on the lower bands.

Lots of possibilities, if only I were retired (again).

73
Evan
AC9TU

Re: Spurs/Harmonics fixes for v4 based on v5 board design?

#64185

Given the issues with spurs and harmonics, any talk of cheap ways
to do an SA?seems entirely appropriate here.?
Perhaps some would prefer not to think about it?

A long winded discussion about a Bitx20 will raise objections here
from a few of those who think it should be all about their uBitx.
And hey, don't be talking about that software stuff!

The HBTE SA discussion was mostly about stringing together a bunch
of ebay modules to create an SA.
The RTL-SDR's can be had on ebay, and require a bunch of other things
strung in there with it to be a functional SA.? I don't see much difference.

I'm happy to discuss this further either here or on HBTE.

/rant

> Since I now see objections to this thread from Mars I am out of it.

Very cool!
Who do you know from Mars?

Jerry, KE7ER

Show quoted text

On Mon, Jan 21, 2019 at 10:40 AM, Bill Cromwell wrote:

The HB in HBTE is for home brew. RTL-SDR and those other gadgets are not home brew. It's doubtful they belong there either. Maybe there is an RTL-SDR group somewhere.

Since I now see objections to this thread from Mars I am out of it.

Re: New ubitx CW not transmitting

#64184

See attached photos of what I mean about going into "Settings" and the ADC value change when I press the key.? Sorry the poor photo quality.? In the second photo, I press the key and the value changes to 0 until I let up on the key, so it is seeing my key presses, yet, it will not go into TX mode during normal operation.? Just sits in RX mode and does nothing.

???

ubitx1.jpg

ubitx2.jpg

Re: Spurs/Harmonics fixes for v4 based on v5 board design?

#64183

Hi Jerry,

The HB in HBTE is for home brew. RTL-SDR and those other gadgets are not home brew. It's doubtful they belong there either. Maybe there is an RTL-SDR group somewhere.

Since I now see objections to this thread from Mars I am out of it.

73,

Bill  KU8H

Show quoted text

On 1/21/19 1:20 PM, Jerry Gaffke via Groups.Io wrote:
The discussion here thus far seems appropriate for this bitx20 group.
If we're running off into the weeds on SA's much further though,
might want to move it over to the HBTE group.
Jerry
On Mon, Jan 21, 2019 at 10:04 AM, Jerry Gaffke wrote:
There has been some discussion lately in
    /g/HBTE/messages?expanded=1
    about various approaches to building a spectrum analyzer.

-- 
bark less - wag more

Re: New ubitx CW not transmitting

#64182

Hi Curt,

Thank you for your reply.

I think I have seen the diagram if you want to use a paddle, then you need to use use different value resistors for the dit and dah respectively.? I'll research that after I get the straight key working.

As I mentioned in my original post, going into the ubitx "Settings", specifically "6:Setup>Read ADC" the bottom line shows 1032.? When press the key, it changes to zero.? When I release the key, it goes back to 1032, so the Aurduino is getting the information, so the connections have to be ok - ???? Seems the Aurduino is not sending the information on to the TX relay/logic - ???

PTT and the mic work fine.? TX led changes, and I get motion on the power meter.

It's a mystery...

Allen KC8VRI

Re: New ubitx CW not transmitting

#64181

Hi,

I have a V3 uBitX and now running the CEC software. I don't recall an "ADC" menu item so I don't know what that is for. I did just look through the setup menu on mine and I see "ADC line monitor". I will have to look it up in the manual to see what it's for. I must have blown by it thinking it is for some mod that I have not installed.

73,

Bill  KU8H

Show quoted text

On 1/21/19 1:25 PM, howellubeen@... wrote:
Hi Bill,
Thanks for your reply.
Yes, when I PTT the mic (and talk), the unit goes into TX mode and my external power/water meter moves back & fourth.? When I key down on the straight key, the display, nor the TX led, nor the power meter give any indication of CW being transmitted.
With the straight key installed, it stays in RX mode, however, the when I key from the ADC setting, the value changes from 1032 to 0 when I key down, so the Aurduino is getting the key press.? Seems the Aurduino is not sending the key press to the TX circuit - ???

-- 
bark less - wag more

Re: ubitx or bitx 40

#64180

I have both. Two different radios. They have a lot ifsimilarities, a lot of differences. If you are only going to get one, get the uBitx as it is the entire HF band, not just 40 meters.
--
72 and God bless
KD4EPG

Re: New ubitx CW not transmitting

#64179

Hi Bill,

Thanks for your reply.

Yes, when I PTT the mic (and talk), the unit goes into TX mode and my external power/water meter moves back & fourth.? When I key down on the straight key, the display, nor the TX led, nor the power meter give any indication of CW being transmitted.

With the straight key installed, it stays in RX mode, however, the when I key from the ADC setting, the value changes from 1032 to 0 when I key down, so the Aurduino is getting the key press.? Seems the Aurduino is not sending the key press to the TX circuit - ???

Re: Spurs/Harmonics fixes for v4 based on v5 board design?

#64178

The discussion here thus far seems appropriate for this bitx20 group.
If we're running off into the weeds on SA's much further though,
might want to move it over to the HBTE group.

Jerry

Show quoted text

On Mon, Jan 21, 2019 at 10:04 AM, Jerry Gaffke wrote:

There has been some discussion lately in? ??/g/HBTE/messages?expanded=1
about various approaches to building a spectrum analyzer.

Re: Spurs/Harmonics fixes for v4 based on v5 board design?

#64177

Yup, as I had said, filter out the strong signals first.

With a signal generator, step attenuator, and RTL-SDR/DVB-T dongle plus upconverter, you could figure out the?
response of the notch filter at both the carrier and at the harmonic/spur frequencies of interest.
The signal generator could an si5351, perhaps filtered to a sine wave though not necessarily.
A good spectrum analyzer with tracking generator would be easier and faster, but is not required.

As a first cut, I wouldn't bother with the notch filter.
Just make sure spurs and harmonics are at least 40 dB down from the carrier.
And learn a whole bunch of skills and tricks that will be useful if you ever get a chance
to play with a better spectrum analyzer.

The SDRplay has a 12 bit ADC, and there are recent attempts at code to
make it more of a spectrum analyzer:???
That might be the next logical step up from an RTL-SDR.
?
There has been some discussion lately in? ??/g/HBTE/messages?expanded=1
about various approaches to building a spectrum analyzer.
I'd like to think something for HF (0-55mhz) with a 100+ dB dynamic range could be kitted up
for a third the cost of that RF Explorer.

Jerry, KE7ER

Show quoted text

On Mon, Jan 21, 2019 at 09:25 AM, Bill Cromwell wrote:

The work-around I saw was using a notch filter to reduce the carrier a specified or known amount. The idea being the carrier is reduced going into the SA but the harmonics are not. Obviously close-in spurs are attenuated too. So it's not good for measuring those unless they are really gross. Nothing is done to the ADC.

The trick is to assure we reduce the carrier without reducing any other part of the spectrum. A good spectrum analyzer with a tracking generator could do that. It would be needed each time the 'trick' was used and adjusted. We might be able to do that but it seems like more of a headache than it's worth. I would have trouble trusting the notch.

Re: New ubitx CW not transmitting

#64176

Hi Allen,

I assume that "SSB is okay" means that you have output when you speak into the mic. Your external watt meter bobs up and down with your speech.

Does the display change to show CW on the display when you try to transmit? Do your hear a relay click when you press the key? If no, it is not being put into CW transmit mode. Check the wiring. If yes then you have left something out of your description. Or...check your wiring.

73,

Bill  KU8H

Show quoted text

On 1/21/19 11:52 AM, howellubeen@... wrote:
My apologies if this has already been answered.? newbie here.? Just installed a new ubitx (4.3) in the  case.  Very enjoyable build.? So far, everything seems to work (had to replace their bad speaker), except CW transmitting.? I plug in a straight key or paddle and it does nothing.? I checked the resistor value - it's OK.? I went into setup, and could see the ADC value go from 1023 to 0 when the key is pressed, so it seems the Aurduino is seeing the key.
PTT SSB transmit works fine, just a dead CW key.
Any advice?
Thanks,
Allen, KC8VRI

-- 
bark less - wag more

Re: Spurs/Harmonics fixes for v4 based on v5 board design?

#64175

Hi Jerry,

The work-around I saw was using a notch filter to reduce the carrier a specified or known amount. The idea being the carrier is reduced going into the SA but the harmonics are not. Obviously close-in spurs are attenuated too. So it's not good for measuring those unless they are really gross. Nothing is done to the ADC.

The trick is to assure we reduce the carrier without reducing any other part of the spectrum. A good spectrum analyzer with a tracking generator could do that. It would be needed each time the 'trick' was used and adjusted. We might be able to do that but it seems like more of a headache than it's worth. I would have trouble trusting the notch.

73,

Bill  KU8H

Show quoted text

On 1/21/19 11:33 AM, Jerry Gaffke via Groups.Io wrote:
If anybody can remember more about this 40dB dynamic range get around, I'd be very curious.
Can't imagine how you would set up an 8bit ADC to get around the dynamic range problem.
Seems the only path is to somehow filter out the strong signal(s).
Would be interesting to tear apart an RF Explorer.
I'd half expect to find a DVB-T dongle buried in there somewhere.
An RTL SDR plus upconverter and step attenuator can be a very useful "toy".
Even if it only has a 40dB dynamic range.
Verifying that spurs and harmonics from a uBitx are at least 40dB down
is about good enough for a 10W rig.? Much better than just hoping.
Educational too.
Jerry
On Mon, Jan 21, 2019 at 08:17 AM, Bill Cromwell wrote:
I read something in an ARRL publication about getting around that 40
    dB dynamic range problem. Maybe by W7ZOI or W1FB. But it almost
    wants a spectrum analyzer to set it up. So it's a circular solution.
    Circular means chasing your own tail :) If you have a spectrum
    analyzer to set it up why do you need the toy analyzer?
It might be doable without a second SA.

-- 
bark less - wag more

Re: New ubitx CW not transmitting

#64174

Allen

I have the same enclosure.? If indeed you have the 4.7k ohm resistor installed (on that board with the connectors that mounts on front panel) -- then it must be a connection issue.?

In this configuration the ubitx will do CW with a straight key - but NOT a paddle.? Use of a paddle requires two specific resistor values than are usually mounted external - so that we can reconfigure for straight key.? [ps you have to dig on the web to find instructions for paddle use with the ubitx keyer - KD8CEC I think has a nice page on this]

With the ubitx in LSB or USB - it 'configures' for CW transmit whenever it measures an appropriate voltage level on this pin of the arduino.? Then key up it is back to receive.? So unlike most rigs - there is not a specific CW mode.? if everything else is working - I suggest it is a connection issue in this path.? Those accessory boards are easy to get solder bridges on - as I found.? If you have the PTT LED installed - it should go red key down - and the LCD should change to CW (only when key down).? So do carefully check the entire path with a DVM to see what is really connected.?

Curt