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Re: Compiler warnings
I wondered on that too.
Some of C++ features are bulky but for Arduino you don't use them. But it makes building reusable code far easier. Encapsulation is a useful one and I don't see any cost for it in the code size. OF course if your that concerned about space....? A good macro assembler for the target machine works. Allison |
Re: Bitx40 75KHz Spurious, How to solve it.
#bitx40
Recommendation:? Use Allard's v2 firmware and associated hardware mods:
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? ?? Moving to a high side vfo using Allard's firmware should fix this spur. When operating at 7.2 mhz with a low side vfo, that vfo is at 12-7.2 = 4.8 mhz. The fifth harmonic of the vfo mixes with the second harmonic of the 12mhz bfo:? ? 4.8*5 = 24? = 2*12 PA4Q (Cor) figured this one out:??/g/BITX20/message/21996 The bfo and vfo have no reason to mix, except that this rig is not shielded. Also, both are being generated inside the si5351, there may be crosstalk there. Going to a high side VFO should work, the vfo is now at 12+7.2 = 19.2 To operate lower sideband as is customary on 40m, the bfo must now be moved down a few khz to the other side of the 12mhz crystal filter. The easiest way to do all of this is to use Allard's v2 code for the Bitx40, he uses the si5351's clk0 to drive the bfo instead of the 12mhz crystal oscillator. Curiously enough, 19.2*5 = 96 = 12*8 So their might still be a slight birdie when operating at 7.2 mhz with a high side vfo but much reduced from the stock low side vfo. Jerry, KE7ER On Sun, Jul 1, 2018 at 10:53 pm, Raj vu2zap wrote:
OK! connected up the bitx40 with Raduino. |
Re: Easy, Inexpensive Cooling Fan, Excelway Case
Hey Arv, If you try the "snubber" diode, you might put a .1uf or maybe even higher value cap across the diode to help take down the little overshoots that will occur even with the diode in most cases. ? Jim, W0EB
------ Original Message ------
From: "Arvo KD9HLC via Groups.Io" <arvopl@...>
Sent: 7/2/2018 8:48:36 AM
Subject: Re: [BITX20] Easy, Inexpensive Cooling Fan, Excelway Case On Sat, Jun 30, 2018 at 04:32 pm, n4eev wrote: |
Re: BITX QSO Afternoon/Evening, Sunday, July 1, 3PM & 7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere.
William Cullison
I really don't have myself setup for portable and I'm on vacation visiting with family in South Carolina so I'm off net for 7 days. 73 Bill WA8VIH/4 On Jul 1, 2018 23:15, "Daniel Conklin" <danconklin2@...> wrote: I didn't try tonight because I have the uBiTX in pieces waiting to get stuffed into a new box?? |
Re: Easy, Inexpensive Cooling Fan, Excelway Case
On Sat, Jun 30, 2018 at 04:32 pm, n4eev wrote:
Arv, you are one smart dude! I love your idea.Haha, well, there are always unforeseen complications. On mine, when I open PTT the fan coasts down and I'm guessing acts like a little magnetic generator and puts quite the whir into the AF signal for a second or two.? I'm thinking the DC pulses produced by the freewheeling fan are of opposite polarity from the PS, so I could snub them with a diode, right? Does sound kinda cool, though.? Maybe not as cool as a "Roger beep" and nobody else (I hope) can hear it. That's what I get for testing the idea on WSPR with the volume all the way down. |
Re: Bitx40 75KHz Spurious, How to solve it.
#bitx40
Dear Akira,
Please share with us the specific details about modifications you used that successfully solved the spurious output problems. Thank you very much and 73 Jerry aa1of |
Re: RFI from uBitx TX after AGC and other mods installed
Rick,
I have a Kees kit and the symptoms are almost exactly as you describe. I don't know that I've heard squeals but otherwise muffled RFI is how I would describe it. Unless Don weighs in with a better variant of this mod I'll probably try Mark's version this morning as that's very simple for others to effect and easier to modify Kees's kit to reflect that change relative to bridging the base/emitter on Q1 with a capacitor. Thanks for the good troubleshooting and persistence- this was a tough bug to swat. John KC9OJV |
Re: Bitx40 75KHz Spurious, How to solve it.
#bitx40
Hi Akira san,
thanks for your update: He said the cause of spurious was the noise of VCC around 19 MHz of 0.15V. As the result of the modifications of Bitx40 to reduce the noise, such as adding the big condenser and choke coil etc , the spurious level went down below of the criteria.That's good news, congratulations! This issue may also be related to the strong "birdie" that can be heard at 7199 kHz when the radio is in LSB mode (almost no birdie in USB mode). It was found that the strength of the birdie greatly depends on the VFO drive level. Default drive level is 4 mA. In the SETTINGS menu, you can try different drive levels (2,4,6,8 mA). The optimum level may be different for each BitX40 radio. The VFO drive level setting may also have an effect on the spurious signals you observed. Perhaps it is possible to fix this issue just by adjusting the drive level setting (in that case, extra hardware modification such as adding capacitor or choke could be avoided). Could you try it out? 73 Allard PE1NWL |
Re: KD8CEC Firmware
What about the Nextion code Ian?
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On Sun, Jul 1, 2018 at 06:10 pm, Ian Lee wrote:
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Re: Bitx40 75KHz Spurious, How to solve it.
#bitx40
Hi!
Thank you for your comment and advice. My friend have found the cause of spurious of 75 KHz. He said the cause of spurious was the noise of VCC around 19 MHz of 0.15V. As the result of the modifications of Bitx40 to reduce the noise, such as adding the big condenser and choke coil etc , the spurious level went down below of the criteria. By this modification, my Bitx40 meets the criteria of the spurious of Japanese regulation. So I am going to submit the application for obtaining the certification of Bitx40 from the relevant authority. There?are two criteria for the spurious. ?? 1)? Baseband area :? under -40db of power of fundamental frequency ??????????? This?frequency range is the 2.5 x? occupied band of frequency of TX mode. ?? 2) Spurious area :? under -50db of power of fundamental frequency. ?????????? This frequency range is the out of Baseband area for super harmonic spurious. The attached files are ? 1) The picture of noise of VCC ?2) The picture of Spurious of 50KHz/div after the modification. ?3) The picture how the modification were added. 73! Akira JJ1EPE |
Re: Homebrew from scratch
#ubitx
Peter Carr
Here is the finished board with the on board Arduino and Si5351 alongside an original uBITX.
|
Re: TX frequency? of uBitx at CWL and CWU mode
#ubitxcw
Hi!
Thank you for your advice and comment. Firstly, I did not consider that frequency displayed on the commercial rigs is TX frequency even though frequency of uBitx is RX. But I am still wondering why the difference of frequency between my ICOM transceiver and uBitx is 1.5Hz but not off set . 1.5KHz might be double of 700 or 800 Hz off set. I think many uBitx user have been making the contact on CWL or CWU?mode by uBitx. So there is something I have not understood about offset of CW. I would like to examine the cause of the frequency difference of 1.5KHz. 73! Akira JJ1EPE |
BFO adjusting procedure
In traditional rigs and in DDS there is a variable capacitor that is used to precisely and easily adjust the BFO or the DDS output. In dongles it can be easily done via the software. Using the 10mhz reference signal or the carrier of any SW broadcast is a matter of seconds to adjust it precisely. As the BFO in my Ubitx is off around 150hz, I wish to know whether there is an easy way to adjust it. My rig is Ubitx ver. 3 and original firmware. |
Re: Bitx40 75KHz Spurious, How to solve it.
#bitx40
OK! connected up the bitx40 with Raduino.
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Yes, there are spurious as reported. The spurious distance from carrier varies with frequency. All the spurs all come together and disappear at near 7.2 Mhz. This is mixing of harmonics but cant remember the maths.. Jerry and others had worked it out. I will try out a filter that I had wired on some board but donno where I kept it! Raj At 02-07-18, you wrote:
Raj, |
Re: Bitx40 75KHz Spurious, How to solve it.
#bitx40
Thanks Allard, goofed there. Will re-hookup the bitx40 later today and see.
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At 02-07-18, you wrote:
Raj, |
Re: Compiler warnings
Jack Purdum
Really? Why do you say that? I find the OOP benefits to be well worth the effort to use them, especially encapsulation. Jack, W8TEE
On Sunday, July 1, 2018, 10:59:38 PM EDT, AA9GG <paul.aa9gg@...> wrote:
C++ and micro-controllers do not really play well together.? That is why I use strictly ANSI C. On Sat, Jun 30, 2018 at 2:11 PM, ajparent1/KB1GMX <kb1gmx@...> wrote: I take them seriously as it impacts future upgrades of the compiler which may --
Paul Mateer, AA9GG Elan Engineering Corp. NAQCC 3123, SKCC 4628 |
Re: Compiler warnings
C++ and micro-controllers do not really play well together.? That is why I use strictly ANSI C. On Sat, Jun 30, 2018 at 2:11 PM, ajparent1/KB1GMX <kb1gmx@...> wrote: I take them seriously as it impacts future upgrades of the compiler which may --
Paul Mateer, AA9GG Elan Engineering Corp. NAQCC 3123, SKCC 4628 |
Re: Running on a Jump Box
The unit is going to draw (amperage wise) what it needs.? You should not limit it.? Now VOLTAGE is a different story, you will want to set that between 12 to 13.8Vdc.? As stated use RV1 to adjust the output power. On Sat, Jun 30, 2018 at 9:43 PM, Gwen Patton <ardrhi@...> wrote: That's extremely interesting and informative, and completely contrary to what I'm trying to do. I like the answers about using the pot on the board to lower the output power. Excellent. I'll probably do that. --
Paul Mateer, AA9GG Elan Engineering Corp. NAQCC 3123, SKCC 4628 |
Re: TX frequency? of uBitx at CWL and CWU mode
#ubitxcw
Sorry if I'm missing something but is there a "user manual" for the Memory Manager? I've never used it before... ThanksOn Sun, Jul 1, 2018 at 9:04 PM, Ian Lee <kd8cec@...> wrote:
--
73 de Glenn VE3JAU Thunder Bay, Ontario |
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