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Yesterday I put in my order for my first BITX. ?I am really looking forward to getting it ! ? ?1. ? Is this LSB only? ? ? ?2. ? Is the new BITX40 cw capable? ? ? ?3. ? If not, can it -easily- be hacked to for cw use? ? ?4. ? Will the original software for the arduino be available in case a re-set from a failed upgrade is needed? ? ?5. ? maybe a basic instructional how-to, or links to such, for programming this adruino be available? ? ?6. ? Will this new version be frequency stable enough to use PSK?
? ?I have been a basic electronics tinker for some time, ps, op-amp projects, basic audio amps, basic repairs etc. ?have built a couple of kits such as the current Rock Mite, pixies and such.? ? ? However, I have had NO experience working with Arduino. ?It has look very interesting to me, however I never took the plunge. ? So I guess its time for me to get on board.
? Thanks in advance for any and all info and advice, positive or negative !
73? Don Frasher ?AD7LL
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Hi Don:
I saw your comment:
?However, I have had NO experience working with Arduino. ?It has look very interesting to me, however I never took the plunge. ? So I guess its time for me to get on board.
and wanted to add my two cents worth. I honestly believe that anyone who is smart enough to pass an FCC license exam is smart enough to use an Arduino. Indeed, I've had students who could barely fog a mirror, yet they learned to program. The really great thing about microcontrollers is that there is a bazillion lines of Open Source code already written for your use. You just compile it into your Arduino and use it. If you want to modify the code for some specialize purpose, then a week with a good C programming book or a free online tutorial would likely be enough.?
My mission is to see more projects with microcontrollers in them, like the Forty-9er VFO/LCD mods in March, 2016, QST. They bring a lot to the table at very low cost. (You can buy a Nano for less than $3.00 and start learning programming.) My BITX40 will soon have a DDS VFO and a 2.4" color TFT display, all driven by an Arduino Mega2560. I was really happy to see Farhan add a Nano-based VFO and LCD display to the BITX40, as frequency agility is one key component to successful QRP operations. Indeed, I'm hoping the new BITX40 will be a club build, as our members enjoy things like NPOTA, FD, and other events where the BITX40 is a viable portable solution without breaking the bank.
I feel we are fortunate to have someone like Farhan as the driving behind the BITX40. Perhaps with one (overly vocal) exception, I think all of us view the BITX40 as a bargain.
Jack, W8TEE
From: "donfrasher@... [BITX20]"
To: BITX20@...
Sent: Saturday, December 24, 2016 10:41 AM
Subject: [BITX20] A few of questions.
?
Yesterday I put in my order for my first BITX. ?I am really looking forward to getting it ! ? ?1. ? Is this LSB only? ? ? ?2. ? Is the new BITX40 cw capable? ? ? ?3. ? If not, can it -easily- be hacked to for cw use? ? ?4. ? Will the original software for the arduino be available in case a re-set from a failed upgrade is needed? ? ?5. ? maybe a basic instructional how-to, or links to such, for programming this adruino be available? ? ?6. ? Will this new version be frequency stable enough to use PSK?
? ?I have been a basic electronics tinker for some time, ps, op-amp projects, basic audio amps, basic repairs etc. ?have built a couple of kits such as the current Rock Mite, pixies and such.? ? ? However, I have had NO experience working with Arduino. ?It has look very interesting to me, however I never took the plunge. ? So I guess its time for me to get on board.
? Thanks in advance for any and all info and advice, positive or negative !
73? Don Frasher ?AD7LL
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This rig is designed to be LSB in conformity of ordinary SSB usage. It can easily be converted to USB by changing the IF frequency (and the band, of course). Think 60m. It can become CW capable by either: 1)injecting an audio tone into the LSB signal (instead of a voice signal), or 2) unbalancing the BFO mixer to allow some of the suppressed carrier through. This will also involve changing the IF slightly (though one can usually get away with it by leaving things more or less as they are). However, note that CW requires a much narrower filter than SSB; you will have to accommodate that somehow. For the software, begin by looking at Farhan's software for the "Mimima" transceiver. If I am not mistaken, that is where he began. I agree with Jack in that you should get to know the Arduino. Parts are cheap; instruction is everywhere on the web and the programming software is free and easily installed. Like everything else worthwhile, there is a learning curve involved but I'm sure that you are up to it. Google "Arduino" and be prepared for inundation! With a DDS, PSK or any of the other digital modes is easily handled, even WSPR. The original FCC-2 had a PSK input as standard equipment. Hope this helps. john AD5YE ---In BITX20@..., <donfrasher@...> wrote : Yesterday I put in my order for my first BITX. ?I am really looking forward to getting it ! ? ?1. ? Is this LSB only? ? ? ?2. ? Is the new BITX40 cw capable? ? ? ?3. ? If not, can it -easily- be hacked to for cw use? ? ?4. ? Will the original software for the arduino be available in case a re-set from a failed upgrade is needed? ? ?5. ? maybe a basic instructional how-to, or links to such, for programming this adruino be available? ? ?6. ? Will this new version be frequency stable enough to use PSK?
? ?I have been a basic electronics tinker for some time, ps, op-amp projects, basic audio amps, basic repairs etc. ?have built a couple of kits such as the current Rock Mite, pixies and such.? ? ? However, I have had NO experience working with Arduino. ?It has look very interesting to me, however I never took the plunge. ? So I guess its time for me to get on board.
? Thanks in advance for any and all info and advice, positive or negative !
73? Don Frasher ?AD7LL
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Thank You !!! ? ? ? LSB only op will be fb. I realized I could do cw via audio tone through the mic jack, ?jack was hoping their was a flip-a-switch option already included. ?Being usable with digi modes is a very big plus fro me, I just wasn't sure if the vfo would stable enough to be practical. ? ? ?As for Arduino, ? Its well past time that i got involved and begin to learn what I might be able to do with. ?As with other , I thank you not only for the information, but also for the encouragement to grow !
73 and Merry Christmas, Don Frasher ?AD7LL?
From: "iam74@... [BITX20]" <BITX20@...>
To: BITX20@...
Sent: Saturday, December 24, 2016 8:34 PM
Subject: [BITX20] Re: A few of questions.
?
This rig is designed to be LSB in conformity of ordinary SSB usage. It can easily be converted to USB by changing the IF frequency (and the band, of course). Think 60m.
It can become CW capable by either: 1)injecting an audio tone into the LSB signal (instead of a voice signal), or 2) unbalancing the BFO mixer to allow some of the suppressed carrier through. This will also involve changing the IF slightly (though one can usually get away with it by leaving things more or less as they are). However, note that CW requires a much narrower filter than SSB; you will have to accommodate that somehow.
For the software, begin by looking at Farhan's software for the "Mimima" transceiver. If I am not mistaken, that is where he began. I agree with Jack in that you should get to know the Arduino. Parts are cheap; instruction is everywhere on the web and the programming software is free and easily installed. Like everything else worthwhile, there is a learning curve involved but I'm sure that you are up to it. Google "Arduino" and be prepared for inundation! With a DDS, PSK or any of the other digital modes is easily handled, even WSPR. The original FCC-2 had a PSK input as standard equipment. Hope this helps. john AD5YE ---In BITX20@..., wrote : Yesterday I put in my order for my first BITX. ?I am really looking forward to getting it ! ? ?1. ? Is this LSB only? ? ? ?2. ? Is the new BITX40 cw capable? ? ? ?3. ? If not, can it -easily- be hacked to for cw use? ? ?4. ? Will the original software for the arduino be available in case a re-set from a failed upgrade is needed? ? ?5. ? maybe a basic instructional how-to, or links to such, for programming this adruino be available? ? ?6. ? Will this new version be frequency stable enough to use PSK?
? ?I have been a basic electronics tinker for some time, ps, op-amp projects, basic audio amps, basic repairs etc. ?have built a couple of kits such as the current Rock Mite, pixies and such.? ? ? However, I have had NO experience working with Arduino. ?It has look very interesting to me, however I never took the plunge. ? So I guess its time for me to get on board.
? Thanks in advance for any and all info and advice, positive or negative !
73? Don Frasher ?AD7LL
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USB should be easy enough. ?
Ashhar has suggested easy hacks to hit other bands, and USB will be necessary for 20m. ?The obvious thing is to move the BFO oscillator to the other side of the crystal filter passband?by adjusting L5, C102, C103. ?The Si5351 has a second unused PLL which could be pressed into service as a BFO oscillator fully under the control of the C program on the Raduino, though performance would likely suffer a bit due to crosstalk between the two Si5351 channels. ?On the plus side, using the Si5351 for the BFO could reduce circuit complexity, perhaps removing Q10 and Q11 entirely. ?(Likewise, the Si5351 allows much of the analog VFO circuitry to be removed.)
Currently, the VFO operates at 5MHz for an operating frequency of 12-5=7MHz. ?If you leave the crystal filter and BFO oscillator where they are and adjust the VFO for 12+5=17MHz,?this should also give USB operation. ?The analog VFO would not be very stable at 17MHz,?but the Si5351 will do fine. ?So switching to USB operation again becomes just a matter of the C program that controls the Si5351.
I'm hoping for something better for CW ops than whistling into the mike. ?The Raduino will likely be used to generate a pure sine wave at 1khz or so, using pulse-width-modulation from one of its counter-timers, and an external RC low pass filter. ?The pwm from the Raduino can change at the start and end of each element for key shaping. ?Some scheme for putting the IRF510 into class C would make CW operation more efficient. ?Adding an XOR gate in there somewhere (at the BFO or VFO?) might make PSK31 transmissions easier to generate from the Raduino. ?A vague possibility we might even decode PSK31 on the Raduino, though a 32 bit processor would be a much better choice. ?(Google "oddwires stm32f". ?Or perhaps a bluetooth module, have an Android smartphone do the decoding?)
Plenty of other ways to generate a CW carrier, though key shaping is not always trivial. ?For example, could use the third output from the Si5351 to drive the final amplifier pretty much directly, shutting down the BFO and VFO Si5351 outputs, keying the dots and dashes by enabling and disabling that third Si5351 output. ?Key shaping might be a matter of messing with the same bias control into the IRF510 that allows us to run in class C mode.
The above is all speculation of course. ?I haven't actually done any of it.
Jerry, KE7ER
---In BITX20@..., <donfrasher@...> wrote :?
? ?1. ? Is this LSB only? ? ? ?2. ? Is the new BITX40 cw capable? ? ?... ? ?6. ? Will this new version be frequency stable enough to use PSK??
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The phase shifting feature within the Si5351 is likely adequate for this. ---In BITX20@..., <jgaffke@...> wrote : > Adding an XOR gate in there somewhere (at the BFO or VFO?) might make PSK31 transmissions easier to generate?
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On Dec 26, 2016 1:56 AM, "jgaffke@... [BITX20]" <BITX20@...> wrote:
> ?Some scheme for putting the IRF510 into class C would make CW operation more efficient.
> of course.? I haven't actually done any of it.
> Jerry, KE7ER
Jerry,
O volt DC bias for IRF510 produces even less output...
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On Dec 25, 2016 12:26 PM, "jgaffke@... [BITX20]" wrote:
>>The Si5351 has a second unused PLL which could be pressed into service as a BFO oscillator fully under the control of the C program on the Raduino, though performance would likely suffer a bit due to crosstalk between the two Si5351 channels.<<?
Those having a lot of experience with the Si5351 have reported that cross-talk is not a problem, particularly if clock1 is shut off and its output grounded, physically separating the clock0 output (for the VFO) from clock2's output (for the BFO).
Jason NT7S's EtherKit Si5351 breakout board addresses potential crosstalk by placing grounded guard vias between the clock outputs. The Adafruit board does not have the guards.
It's just occurred to me that potential crosstalk could also be minimized by using board-edge SMA connectors for the outputs. I would be interested in hearing from anyone who has soldered rg174 (or similar 50 ohm coax) directly to the output pads with no apparent ill effect.
73,
Todd K7TFC
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You're right, moving to class C is more than a matter of changing the IRF510 bias,?will require higher gain in the preceding stage.
Another thing to look into if somebody wants efficiency is class E or F operation on the IRF510 when operating CW or PSK31. ?But that creates even more issues with getting things tuned up, not something that should be included in a kit primarily aimed at being an SSB transceiver.
Even if planning to run CW, easiest to just leave the IRF510 running as a linear as it is now. ?Get a big enough battery. ?But those inclined to tinker might find class C/E/F a fun direction to consider.
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Hi Todd,
I have soldered RG-174 directly to both the Adafruit and Etherkit boards and had great results on the last three projects. I'm using a Etherkit board with a SMA RG-174 pigtail to connect to my BitX40 right now. In all cases I ?have not noticed any cross talk, but I always disable the unused outputs in the Sketch. I don't know if that's what you wanted to know, but it's good to hear from you. The Rouge Valley hasn't been the same since you left:-) Joel? KB6QVI
toggle quoted message
Show quoted text
On Dec 25, 2016, at 1:13 PM, 'Todd F. Carney / K7TFC' k7tfc@... [BITX20] < BITX20@...> wrote:
?
On Dec 25, 2016 12:26 PM, "jgaffke@... [BITX20]" wrote:
>>The Si5351 has a second unused PLL which could be pressed into service as a BFO oscillator fully under the control of the C program on the Raduino, though performance would likely suffer a bit due to crosstalk between the two Si5351 channels.<<?
Those having a lot of experience with the Si5351 have reported that cross-talk is not a problem, particularly if clock1 is shut off and its output grounded, physically separating the clock0 output (for the VFO) from clock2's output (for the BFO).
Jason NT7S's EtherKit Si5351 breakout board addresses potential crosstalk by placing grounded guard vias between the clock outputs. The Adafruit board does not have the guards.
It's just occurred to me that potential crosstalk could also be minimized by using board-edge SMA connectors for the outputs. I would be interested in hearing from anyone who has soldered rg174 (or similar 50 ohm coax) directly to the output pads with no apparent ill effect.
73,
Todd K7TFC
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On Dec 26, 2016 3:13 AM, "jgaffke@... [BITX20]" <BITX20@...> wrote:
>
> You're right, moving to class C is more than a matter of changing the IRF510 bias,?will require higher gain in the preceding stage.
Had both
replaced voltage controlled IRF with transistor 2SC ;)
& 2N3866 @ 24 Volt in preceding stage...
'Repair & Reuse or Recycle E-Waste'
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On Dec 25, 2016 4:29 PM, "Joel Caulkins caulktel@... [BITX20]" wrote:
>>I have soldered RG-174 directly to both the Adafruit and Etherkit boards and had great results on the last three projects. I'm using a Etherkit board with a SMA RG-174 pigtail to connect to my BitX40 right now. In all cases I ?have not noticed any cross talk, but I always disable the unused outputs in the Sketch.<<
Thanks, Joel. Yes, that's the kind of experience I wanted to hear about. I like the idea of using the SMA connectors, and I recently bought a few dozen of male and female, but they are a bit costly relative to the Si5351 boards themselves. At $2.50 each for the PCB-edge females, they almost cost as much as the board. If they're not really necessary, others can avoid the expense.
No reflection on you, of course, but I don't find myself missing the Rogue Valley very much. I like it here in the Portland area--the land of W7ZOI and NT7S. Did you know there are still fully-stocked Radio Shack stores up here?
Once I get my BitX40 fully working, we should try for a BitX-to-BitX QSO. Even with lousy ionospherics, we ought to be able to manage 290 miles with 5 watts.
73,
Todd K7TFC
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Todd,
You're on for a Bitx to Bitx QSO, i have done it several times with NT7S. This was done with my MST 400 at 7 watts.?
Joel KB6QVI
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Show quoted text
On Dec 25, 2016, at 10:24 PM, 'Todd F. Carney / K7TFC' k7tfc@... [BITX20] < BITX20@...> wrote:
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On Dec 25, 2016 4:29 PM, "Joel Caulkins caulktel@... [BITX20]" wrote:
>>I have soldered RG-174 directly to both the Adafruit and Etherkit boards and had great results on the last three projects. I'm using a Etherkit board with a SMA RG-174 pigtail to connect to my BitX40 right now. In all cases I ?have not noticed any cross talk, but I always disable the unused outputs in the Sketch.<<
Thanks, Joel. Yes, that's the kind of experience I wanted to hear about. I like the idea of using the SMA connectors, and I recently bought a few dozen of male and female, but they are a bit costly relative to the Si5351 boards themselves. At $2.50 each for the PCB-edge females, they almost cost as much as the board. If they're not really necessary, others can avoid the expense.
No reflection on you, of course, but I don't find myself missing the Rogue Valley very much. I like it here in the Portland area--the land of W7ZOI and NT7S. Did you know there are still fully-stocked Radio Shack stores up here?
Once I get my BitX40 fully working, we should try for a BitX-to-BitX QSO. Even with lousy ionospherics, we ought to be able to manage 290 miles with 5 watts.
73,
Todd K7TFC
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Todd K7TFC
Joel Caulkins/N6ALT