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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 |
Re: Antuino support group opened -- early antuino question
Evan,
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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/56219 But 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. |
Re: Narrow filter for CW
#ubitxcw
¿ªÔÆÌåÓýI use a simple sofa beams filter in my audio chain. It works fantastic. Check it out at https://www.dxengineering.com/parts/sbm-lb-module-cw?seid=dxese1&gclid=EAIaIQobChMI1dqE3puD5AIVA9vACh1ZLg6MEAQYASABEgJYifD_BwE.
David Posthuma
WD8PUO
Get
? From: [email protected] on behalf of Evan Hand <elhandjr@...>
I am traveling on business, so can not get at the documentation on the CEC software.? From memory I am sure that one of the control shifts the signal on the "roofing" 45 mhz filter to act as a gain control.? The filter skirts of the single crystal would be
more gradual than the sharper skirts on the 12/11 mhz SSB filter.? The other is moving the BFO to change where the signal is received relative to the SSB passband.? I just do not remember which one is which without the documentation.??Sent: Wednesday, August 14, 2019 4:30 PM To: [email protected] Subject: Re: [BITX20] Narrow filter for CW #ubitxcw ?
Since you are moving the center of the signal across the pass band of the filter you should be able to move the signal up against one side or other of the skirt of the SSB filter to narrow the received signal.? My use of the CEC sliders has not been very precise.? To make the software work more efficiently for the operator, I would look at adding another encoder in place of the Nextion slider.? Issue is what I/O do you give up to connect it to.? Another option would be to use a switch to toggle the frequency encoder to do both frequency and IF shift.? Would be better than what I have used on the Nextion screen.? Response there is not always accurate. Above are just ramblings.? Please take with a grain of salt. 73 Evan AC9TU |
Re: Narrow filter for CW
#ubitxcw
I am traveling on business, so can not get at the documentation on the CEC software.? From memory I am sure that one of the control shifts the signal on the "roofing" 45 mhz filter to act as a gain control.? The filter skirts of the single crystal would be more gradual than the sharper skirts on the 12/11 mhz SSB filter.? The other is moving the BFO to change where the signal is received relative to the SSB passband.? I just do not remember which one is which without the documentation.??
Since you are moving the center of the signal across the pass band of the filter you should be able to move the signal up against one side or other of the skirt of the SSB filter to narrow the received signal.? My use of the CEC sliders has not been very precise.? To make the software work more efficiently for the operator, I would look at adding another encoder in place of the Nextion slider.? Issue is what I/O do you give up to connect it to.? Another option would be to use a switch to toggle the frequency encoder to do both frequency and IF shift.? Would be better than what I have used on the Nextion screen.? Response there is not always accurate. Above are just ramblings.? Please take with a grain of salt. 73 Evan AC9TU |
Re: Narrow filter for CW
#ubitxcw
I guess an audio active filter 200hz wide like the Hipermite by 4SQRP might suffice. Il 14/ago/2019 19:59, "Curt via Groups.Io" <wb8yyy=[email protected]> ha scritto: Dave |
Re: Antuino support group opened -- early antuino question
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? 73 Evan AC9TU |
Re: Narrow filter for CW
#ubitxcw
Dave
I sense we have thrown lots of choices at you.? Except for playing with IF shift, implementing an audio filter is easiest - with many low cost choices around.? Note in most respects the design architecture is very similar across v3, v4 and v5.? v5 was a larger change with a different IF selection for the SSB crystal filter.? Many of us have rigs with 4915 kHz xtal filters made from cheap xtals.? Sounds like it could be installed in parallel with the 12 MHz filter without needing relays -- I should have thought of that - but we need a rig control to command the ubitx to 'Receive CW' to change the oscillator functions as Asher describes.? Except in a major contest maybe, I find the audio filter is entirely sufficient with the way ubitx receive gain is distributed.? You might find CW transmit behavior a bit strange but it works fine once you are used to it.? Curt |
Re: Antuino support group opened -- early antuino question
Ashhar and Jerry -- thank you so much for the reply and info.? I better understand the general antuino application.? It is not a inline SWR/pwr meter, but it does a thousand other equally or more important jobs.? I'm always borrowing VNA from club members.? When I get a Antunio, I can stop being a pain in the neck to others. hahah.
P.S. I showed your email to my wife, and breathlessly exclaimed...look at this...Ashhar wrote to me!!!!? I did a little dance and told her I would never delete his email. [Obviously I need to get out more, but it is nice to have a few heroes out there, and you fit the bill. So a thousand thanks for all you've accomplished for all of us.? Okay, now I will stop sucking up. hahah.] Don km4udx |
Re: Issues with ordering the BITX40
I have just checked this link On Wed, Aug 14, 2019 at 3:25 PM MVS Sarma via Groups.Io <mvssarma=[email protected]> wrote:
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Re: Narrow filter for CW
#ubitxcw
Ash
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Does this option work on the V3 or V4 radios as well. Now to source more data on this option. Evan Yes as I mentioned I have the nextion display on most of my ubitx radios. I noticed that the IF shift when slid from one side to the other can make certain tones disappear and reappear I guess I should move it to one side or the other and see if I can use it to isolate. I assume it is a one way shift on the receive side only. Thanks to all that wrote thoughtful replies. On Mon, Aug 12, 2019 at 08:10 PM, Ashhar Farhan wrote:
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Re: Issues with ordering the BITX40
At the 2nd link, below the photo you can see "BUY" button. Us e it to rea h ordering page. On Tue, 13 Aug 2019, 11:25 pm Jerry Gaffke via Groups.Io, <jgaffke=[email protected]> wrote: I'm still not seeing any way to buy a raduino from . |
Re: Antuino support group opened -- early antuino question
The Antuino looks like a useful tool, well packaged.
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I plan to get one. But it won't be a replacement for your MFJ? power meter and SWR meter. As Farhan pointed out, it would be very inconvenient to keep the Antuino tuned into the frequency of the transmitter, the Antuino only sees one frequency at a time where the MFJ is broadband.? And while the Antuino can measure the SWR of your antenna, I don't think it can measure the SWR of an antenna while the transmitter is connected. It could be used to measure the power coming out of a transmitter if you have an appropriate resistive attenuator between the transmitter and the Antuino. A small wire antenna on the Antuino might be used instead of the attenuator, but the signal level seen by the Antuino will then vary with frequency and distance and where your cat happens to be sitting. Be very careful if using the Antuino around a transmitter, it would be easy to feed it too much power and blow it out. Jerry, KE7ER ? On Tue, Aug 13, 2019 at 06:50 PM, Ashhar Farhan wrote:
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Re: Antuino support group opened -- early antuino question
Don, The answer is yes, but ... the Antuino needs to be tuned within 10 khz of the ubitx to receive and display the modulation. Being as sensitive as it is, you dont even need to connect it with the tap. A small piece of wire in the RF IN will pick up thr ubitx transmission. - f On Wed 14 Aug, 2019, 1:24 AM Don - KM4UDX, <dontAy155@...> wrote: I have an early question (even before the support groups gets up and running...hahaha) |
Re: What is the current version board? I have been away from the forum for awhile
The version differences are driven by hardware changes.
Harmonics have been reduced by a different board layout for the low pass filters. Spurs reduced through a 90mhz low pass filter addition between the if stages.? Best would be do download the information from HF Signals web site. The other change is to the SSB fcrystal filter.? The center frequecncy was changed from 12 mhz to 11.055 mhz to reduce interference from so of the Nano clocks that are close to 12 mhz (the USB converter). With out the hardware changes, the code would not work, and there is not significant changes in operation other than in the calibration procedure.? The new firmware goes into transmit mode to set calibration, so a dummy load or 10 mhz antenna is required. Above are what I remember, and I may have missed some significant changes, especially to the firmware, as after I go my v5 board running, I quickly installed the kd8cec firmware and Nextion display. All of the test that I have done so far indicate that the harmonics are solved with the changes.? I do no have a good enough spectrum analyzer to verify the spurs, though others have reported significant reductions. 73 Evan AC9TU |
Re: starting point
On Tue, Aug 13, 2019 at 12:54 PM, Evan Hand wrote:
I agree with Don, Dean and Skip.? I have built 2 version 4 and 1 version 5.? The first went smoothly because I did follow the steps in Don's message.? The second one I had issues with because I jumped into the mods before I had the rig working.? The last one I followed the formula and had no issues. |
Re: Antuino support group opened -- early antuino question
I have an early question (even before the support groups gets up and running...hahaha)
Is the Antuino able to be left in line with a tap & pad or something as a semi permanent basis to my uBITX? Right now I have an old MFJ power/SWR meter hooked up after the uBITX and before the antenna.? Is there a way to replace the swr/pwr meter with the? Antunio? thanks! Don km4udx |
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