Re: Antuino support group opened -- early antuino question
I don't think anyone has mentioned the nanoVNA.? These go from 50 kHz up to 900 MHz, color touch screen, built with rechargable battery and PC sw.? They cost less than 70 USD.? Look at? /g/nanovna-users/It is strong competition I am afraid for the antuino,? Though I will probably still get an antuino because it will no doubt be the learning and experimentation platform that the BitX radios have become.
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The sotabeams filters are exceedingly good technically.? It¡¯s the flexibility and user interface that¡¯s stinks.? And, of course, it can¡¯t be modified, even though the processor has plenty of resource for additional computational things like a nice display to graphically show you the filter contour. ? ?
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From: [email protected] [mailto:[email protected]] On Behalf Of David Posthuma
Sent: Wednesday, August 14, 2019 7:33 PM
To: [email protected]; [email protected]
Subject: Re: [BITX20] Narrow filter for CW #ubitxcw? The sofa beams Audio DPS boards...there are several models...are stand alone boards, no coach needed. Simply insert in your audio chain and add power. It works great. Far better than I had hoped. They are worth the investment.
On Tue, Aug 13, 2019 at 07:42 AM, MadRadioModder wrote: I use my own coded version of this thing
That looks like a cool implementation. Is your audio bandpass filter stand alone or is it an add-on to the Sotabeams filter board?
It sounds like it is a stand alone DSP filter and display.
Is the code on GitHub or somewhere?
Tom, wb6b -- ¡_. _._
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Stand alone just like you see in the picture.? Uses the Audio Adapter/ Shield board from prjc.com, a Teensy 3.6, a small SPI 7735 display, two encoders, and two LEDs.? That¡¯s it.? Custom code.? Not published yet. ? ?
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From: [email protected] [mailto:[email protected]] On Behalf Of Tom, wb6b
Sent: Wednesday, August 14, 2019 6:37 PM
To: [email protected]
Subject: Re: [BITX20] Narrow filter for CW #ubitxcw ? On Tue, Aug 13, 2019 at 07:42 AM, MadRadioModder wrote: I use my own coded version of this thing
That looks like a cool implementation. Is your audio bandpass filter stand alone or is it an add-on to the Sotabeams filter board?
It sounds like it is a stand alone DSP filter and display.
Is the code on GitHub or somewhere?
Tom, wb6b -- ¡_. _._
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Success.? The problem turned out to be a short between the mic audio line and ground.? Sunil from amateurradiokits.in had sent me a second front panel PCB after I reported my initial problem to him. (His customer services has been awesome and very responsive.)
I could not figure out where the short was - so I wired up a the new PCB - using a smaller iron tip and smaller gauge solder.? No short this time.? I can report that the Uniden/Cobra mic with the 4 pin connector works fine - completely unmodified. ??
Here is a video of the completed rig receiving (sans the send/receive LED which I still have to wire up)
Thanks everyone for the help and advice. ?
Dean
KK4DAS
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Curt -- I can reflow each pin if I pull up my pants and stop being a whousssssss.
Good implyed question on the drive level. SWR meter says 28w on wspr on 80m, which means two full minutes of hard duty. ?But I don't know what band it was on when it locks up. ? I was so freeked about how it could be in drive when there was no TX command from my computer, a disconnected sound card, a reboot, a physical turn off/on, that I didn't notice what the band or pwr level was. I feel silly now not noticing that.?
I'll look for any anomolies on the board. ?The "case" has a lot of air flow, so something could have landed where it wasn't supposed to be.?
The lock up is seemingly random, so I can't make it misbehave on command (yet). ?If it keeps up, I'm sure that even I will figure out the pattern. hahah. ?This is the third time so far.?
If i decide to replace it, I assume the required relay is the axicom ?V23105A5403A201 discused (endlessly) in previous threads?
Given that I may need only one, there must be some uBITX builder who got 5 or 10 and would send me 1 or 2 (pleaseeeee..)?
Don
km4udx
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I've been reading the topics regarding the ssm2167 with much interest.? So finally I integrated the board into my ubitx v5. I ended up with a trimmer on the output of the board, and pots on the compression, and noise gates.? ?The problem I ran into is that on the air, rotating the 100K pot I had for compression had little to no effect, but I was getting compression as it was clearly audible on the air.?
I read the data sheet more thoroughly on the ssm2167 and found that the input voltage has to be quite low. -20 to -30 dBV or so.. measuring the electret microphone output on the scope, yielded much higher.. aha..I thought.. I need yet another pot to trim the input voltage. I still needed the 5V to get to the electret so I wanted the trimmer past the 0.1 uF on the board..:-(? so I took of the 0.1 uf cap off the board, and made connections for the trimmer post 0.1 uF cap. So now 3 pots and one trimmer. Trimmer adjusts the output voltage, pots are input voltage to the board, compression and noise gate.? ?On the air..no compression sounds like no compression.. and turning up the pot makes now a profound difference in on the air sound with a LOT of punch. the Power meter goes way up with compression now. What I believe was happening is that the input was so high that I was in the limiting portion of the transfer curve for the ssm2167, and now I'm back in the linear portion, and all is well!? My problem is that it would really be good to have the trimmers on a board, so maybe I'll design a board to accommodate the changes.?
73
Brad N8YG
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The sofa beams Audio DPS boards...there are several models...are stand alone boards, no coach needed. Simply insert in your audio chain and add power. It works great. Far better than I had hoped. They are worth the investment.
David Posthuma
WD8PUO
Get
?
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From: [email protected] on behalf of Tom, wb6b <wb6b@...>
Sent: Wednesday, August 14, 2019 7:37 PM
To: [email protected]
Subject: Re: [BITX20] Narrow filter for CW #ubitxcw
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On Tue, Aug 13, 2019 at 07:42 AM, MadRadioModder wrote:
I use my own coded version of this thing
That looks like a cool implementation. Is your audio bandpass filter stand alone or is it an add-on to the Sotabeams filter board?
It sounds like it is a stand alone DSP filter and display.
Is the code on GitHub or somewhere?
Tom, wb6b
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The 12/11mhz crystal filter is after all IF amps on receive. The IF amps are operating at very low signal levels, most of the gain is in the audio amps. It's the audio pre-amp (a 2n3904 just before the volume control) that overloads first, by a very wide margin:? /g/BITX20/topic/5945215That thread is about the Bitx40, but the uBitx will have the same issue. So, if you have a very strong CW station 500 hz away from the weak signal you are trying to hear, the strong signal will cause audio distortion in that audio pre-amp and any audio filter that follows the pre-amp won't be able to clean it up. The solution is to have a choice of wide crystal filter for SSB, and narrow for CW. But that's not a big deal for most of us, easier to implement the audio filter for CW. Jerry, KE7ER ? Jerry, KE7ER
On Wed, Aug 14, 2019 at 04:56 PM, Tom, wb6b wrote:
It would seem the reason for this is, the crystal filter may filter out the strong unwanted signal while the signals are still in the first stages of the IF chain. The signals are still relatively weak at this point and the undesired signal is removed before it can get amplified to the point that overloading starts to occur.?
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Don
First before we assume its a bad relay, reflow each pin and also reduce the transmit drive level. You never know the relay may be okay. I assume you tried more than one band? Make sure you don't have a small strand of wire to blame for this mishap.
Curt
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On Tue, Aug 13, 2019 at 05:50 AM, Jack Purdum wrote:
Inexpensive DSP is incorporated into the JackAl board.
The JackAl board looks like it is a good all in one upgrade to the uBitx.? So it looks like, in all but the more extreme cases, people are happy with DSP audio bandpass filters. Crystal CW filters can provide some additional protection from overloading from a strong close by frequency signal. It would seem the reason for this is, the crystal filter may filter out the strong unwanted signal while the signals are still in the first stages of the IF chain. The signals are still relatively weak at this point and the undesired signal is removed before it can get amplified to the point that overloading starts to occur.? Tom, wb6b
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On Tue, Aug 13, 2019 at 07:42 AM, MadRadioModder wrote:
I use my own coded version of this thing
That looks like a cool implementation. Is your audio bandpass filter stand alone or is it an add-on to the Sotabeams filter board? It sounds like it is a stand alone DSP filter and display. Is the code on GitHub or somewhere? Tom, wb6b
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You are welcome! Just learning myself. Best regards,
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On Aug 14, 2019, at 5:33 PM, Dean Souleles < dsouleles@...> wrote: Thanks Jim!
Where were you three weeks ago?? :)
My experience exactly.
Your straightforward post will really assist new builders,
Dean
KK4DAS
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Re: Issues with ordering the BITX40
I know but I couldn't find the original Raduino on HFsignals
On Wed, Aug 14, 2019 at 5:29 PM JT Croteau < jt.tobit@...> wrote: Ken, that is the Raduino clone by Sunil.
Could this be the Raduino link?
73
Ken VA3ABN
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hello all! My beloved V4 uBITX has been working really hard and flawlessly 24/7 in wspr mode for (almost) months at a time. ?The results are impressive...frequently in the top 10 worldwide 2 way spot ranking. ?But all that success comes at a price.? Now, my uBITX randomly sticks in TX mode. ?If I tap the left side relay, it releases TX mode. ?I learned that diagnostic technique from?Dave_ K0MBT (hahah, and thank you!). ?If I just reboot or turn off/on, it stays in TX mode. ?But the back of the pen allways works. ?So am I good to go to replace the relay? I really hate to mess with it, but my hand is forced, as they say. Is there a prefered type/source of replacement relay??  thank you all!!!! Don km4udx
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Thanks Jim!
Where were you three weeks ago?? :)
My experience exactly.
Your straightforward post will really assist new builders,
Dean
KK4DAS
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Re: Antuino support group opened -- early antuino question
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Re: Antuino support group opened -- early antuino question
Jerry,
Thank-you for the clarification.?
I was aware that you can measure SWR with just the scaler values, as I have built a resistor bridge based scanning SWR antenna analyzer, and purchased a cheap VNA with Smith chart capability.? I wanted to make sure that I had not missed something based on Don's mention of using the VNA capability of the Antuino??
73
Evan
AC9TU
AC9TU
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Re: Antuino support group opened -- early antuino question
Evan, Looking at the Antuino schematic, it has an AD8307 at the output of the 25mhz filter to tell the processor the magnitude of the received signal. Nothing to tell the processor anything about phase. So it's an SNA (Scaler Network Analyzer), not a VNA (Vector Network Analyzer) You might think it needs both phase and magnitude to determine the SWR of an antenna. But no, it uses a bridge circuit, and senses the difference between what the antenna does to the signal and what a 50 ohm resistor does to the signal.? It assumes a 50 ohm environment.?? From post? ? /g/BITX20/message/63034? I suppose R21,R29,R16, and an antenna on P3 would form a balanced ? bridge when the antenna is 50 ohms, CLK1 is driving the antenna and the top of the bridge. ? The ADE-1 RF port sees any imbalance across the bridge. ? CLK2 into the LO port is 25mhz above (or below) CLK1. The cheapest VNA that I am aware of is the Vector Impedance Analyzer kit that Kees sells, toward the bottom of this webpage:? ??? Some other VNA's mentioned here:?? /g/BITX20/message/56219But I haven't looked over what's available out there for several years. Jerry, KE7ER
On Wed, Aug 14, 2019 at 01:14 PM, Evan Hand wrote:
I have ordered my Antunio, and am waiting for delivery, anxious to try it out .? The above comment from Don raises one question for me:? Is it a VNA or SNA.? As I understand the difference is that the VNA measures the phase angle as well as the magnitude of the impedance, an SNA just measures the magnitude of the impedance.? in reading the description on the HF Signals Web Page it states SNA capabilities.
As far as output, you can get a Smith Chart from a VNA, not from an SNA.
So the question is if the hardware would support a VNA application, and and if so does the software provided have both the real and imaginary values of the impedance?
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MadRadioModder
David Posthuma
Jim Willis