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Re: Spurs/Harmonics fixes for v4 based on v5 board design?
Thanks. Interesting.? I already replaced all relays with Axicom and L5 and L7.? What other mods might help this particular spur?
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On Sun, Feb 3, 2019 at 08:49 PM, Raj vu2zap wrote:
Dave, |
Re: uBITX default frequency
John,
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Tune to whatever freq. you want and switch VFO from A to B. Now the freq. A becomes default. Switch back to VFO A. Raj At 04-02-19, you wrote:
Hi Keith |
Re: uBitX PTT cycling
For mobile ops I had to add a filter to eliminate the alternator whine. I used an old Radio Shack filter that I had in a car for 2m FM decades ago, and just mounted it in the case running the 12v input through it ahead of the power switch. I had already installed a 12v regulator chip for the main board, bypassing it for the PA, just in case the car voltage excursions could be dangerous...I see as high as 14.1v sometimes when the engine is running. I also had already used an old Motorola speaker mic from my junkbox, and had a switch on the panel to change from the internal speaker to the speaker mic, and find that handy when mobile as I can hold the mic closer to my ear if the ambient noise is high. Other than that. no other mods. The only issue I noted on this trip was that my speaker, which was hot-glued to the plastic case, came loose. I suspect leaving the rig in the car with temps well below freezing, then warming up to the 50's, and traveling over some significant potholes may have weakened that bond, but I'll look at that further. On my return trip from Newport News, VA to my home in Eastern PA I I had a nice chat with a station in Erie, PA, who had solid copy on my 7w radio.
=Vic= |
Re: The sun orbiting the earth, spectrum analyzers and the uBITX
Absolutely, I am very happy with these solvable imperfections. At the beginning I thought it was like solving a partial differential solution without solution at all. I was wrong, the beauty of the uBitx resides in its multiple solutions. Il 04/feb/2019 11:23, "Tom, wb6b" <wb6b@...> ha scritto: Yes, it is amazing how far they got with the wrong planetary system. |
Re: The sun orbiting the earth, spectrum analyzers and the uBITX
Yes, it is amazing how far they got with the wrong planetary system.
I guess what I'm saying is, the struggle our forefathers were having to work out the kinks in (for example) the planetary model of the time, led to amazing increases in knowledge as they worked things out. ? If the uBITX had been perfect from the start we might be happily talking away and our knowledge advanced to just where the knobs are and how to connect the antenna coax connector. But, because there are things about the uBITX that beg to be improved, we started working on solutions and are increasing our knowledge in the process; either by our own experiments or reading what the others on the group try and either succeed or not.? So (within limits) working with things with imperfections or kinks can lead to an adventure of learning that something that goes really smoothly may not provide. Because of the happenstance of buying the uBITX with it's current kinks, I've been launched into learning more than if the uBITX had just been a hook up a microphone and talk situation. Certainly nowhere, anywhere near a Newton or Kepler, but I'm happy for the modest level learning the uBITX has brought about.? Tom, wb6b |
Re: The sun orbiting the earth, spectrum analyzers and the uBITX
Timothy Fidler
My take on the Sun orbiting system (Ptolemaic) is ya gotta give the guy credit.? Based on this concept and some magic algorithms the ancients managed to predict , so they say,? eclipses, rising times of planets and all sorts of cosmic ephemera.? I suspect that they predictions would get well out of wack after a year or two as they must have been the equivalent of binomial expansions ... sort of vaguely linearising stuff to theories that were flawed. ...
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.Now is the Ubitx the Ptolemaic system and the? xiegu 108g the? uBitx after a modern day Issac Newton has fooled with it.?. perhaps that is the question that will get me zip tied and run out of town :-) .. backwards on a hoss.. Timothy E. Fidler : Engineer BE Mech(1) Auckland , NDT specialist AINDT UT /RT3 , MT2 CB #2885,?
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Re: The sun orbiting the earth, spectrum analyzers and the uBITX
Ours may be more called 'Learning by Tinkering' :), which involves some but not that much thinking, luckily enough! Il 03/feb/2019 22:18, "Tom, wb6b" <wb6b@...> ha scritto: Hi, |
Re: VCO and display don't match on UbitX?
No, 40m lbs with mic. Bill ---------- Original Message ---------- From: "Gary Anderson" <gary.ag5tx@...> To: [email protected] Subject: Re: [BITX20] VCO and display don't match on UbitX? Date: Sun, 03 Feb 2019 19:47:04 -0800 Bill,? Confused about the replies to your question. Is this is factory firmware in CW mode with a sideTone of 1 KHz perhaps? ? if (txMode == TX_CW){ ? ? //turn off the second local oscillator and the bfo ? ? si5351bx_setfreq(0, 0); ? ? si5351bx_setfreq(1, 0); ? ? ? //shif the first oscillator to the tx frequency directly ? ? //the key up and key down will toggle the carrier unbalancing ? ? //the exact cw frequency is the tuned frequency + sidetone ? ? if (isUSB) ? ? ? si5351bx_setfreq(2, frequency + sideTone); ? ? else ? ? ? si5351bx_setfreq(2, frequency - sideTone);?
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Re: Spurs/Harmonics fixes for v4 based on v5 board design?
Good Morning Raj, Finally a day would come, like Farhan indicated that cost of AD8307 increased from 2 to 10$. ?these Axicom relay specific model also be north bound in prices. regards sarma On Mon, Feb 4, 2019 at 10:20 AM Raj vu2zap <rajendrakumargg@...> wrote:
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Re: Spurs/Harmonics fixes for v4 based on v5 board design?
Dave,
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Spurs zero in every 2.5MHz. Some move at 3x others 5x the tune speed. ex: .....15,17.5,20, 22.5 and so on Mhz. Raj Chenge of relays reduces them greatly along with other mods. At 04-02-19, you wrote: Hmm The numbers don't seem to add up for this spur.? When at 7.15MHZ it was at 5mhz when at 8.5 it was around 8MHZ spur. |
Re: ubitix v4
The transistor must be running really hot!
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Raj At 03-02-19, you wrote:
I just soldered a third silicon diode between the original ones (the foil cut of course). No distortion anymore. |
Re: The sun orbiting the earth, spectrum analyzers and the uBITX
Tom
Indeed its a nice enough assemble a radio experience for hams around the world. Its issues are sufficiently addressable. Here I was struggling in installing Gordon's external relay board,? only because I didn't understand its interfaces. Finally it's working,? to address the harmonic spurious. I have the simple v5 version of the 45 MHz filter installed in the transmit path. I may not have it measured for a while, but these should be improved. Moving back to evaluating simple agc solutions,? and supporting those in my local club build. Curt |
Re: VCO and display don't match on UbitX?
Bill,?
Confused about the replies to your question. Is this is factory firmware in CW mode with a sideTone of 1 KHz perhaps? ? if (txMode == TX_CW){
? ? //turn off the second local oscillator and the bfo
? ? si5351bx_setfreq(0, 0);
? ? si5351bx_setfreq(1, 0);
?
? ? //shif the first oscillator to the tx frequency directly
? ? //the key up and key down will toggle the carrier unbalancing
? ? //the exact cw frequency is the tuned frequency + sidetone
? ? if (isUSB)
? ? ? si5351bx_setfreq(2, frequency + sideTone);
? ? else
? ? ? si5351bx_setfreq(2, frequency - sideTone);?
Rgds, Gary |
Re: VCO and display don't match on UbitX?
Calibration procedure was described? by Farhan. Pl see the hfsignals website. All the? best.
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Re: VCO and display don't match on UbitX?
Bill
enjoy the cool new rig and take some more data.? a bit larger error than my recent uBITX.? yes the usual convention is to display the (missing) carrier frequency for SSB.? see if data is consistent across 40m and check at least one other band.? there is a calibration procedure to adjust it.? [plus others will cite an alternative firmware version if you are so inclined, I am still using stock firmware for now] meanwhile as long as you stay within the band - enjoy the rig.? I am QRV in blue also.? Curt WB8YYY |
Re: Spurs/Harmonics fixes for v4 based on v5 board design?
Hmm The numbers don't seem to add up for this spur.? When at 7.15MHZ it was at 5mhz when at 8.5 it was around 8MHZ spur.
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Previously uploaded the pic of the inductors in previous post. Two pics show two tone at 7.15MHZ and 8.5MHZ? Can see the spur moves from around 5 to around 8 MHZ. Any ideas the cause and/or how to eliminate it? Thanks. ? On Fri, Feb 1, 2019 at 10:14 PM, Raj vu2zap wrote: What inductors did you use, please share a pic. |
The sun orbiting the earth, spectrum analyzers and the uBITX
Hi,
I was reading something on the history of astronomy and an amusing thought came to mind.? If it weren't for early astronomers banging their heads against the wall trying to explain the complex cyclic paths of the planets orbiting around the earth we may have not been gifted some amazing math. This provided to foundation for developing?fourier analysis and likely the calculus. (and a way to discover/prove the original assumption was wrong.) And because of the birthing issues of the uBITX and so many people interested in finding ways to improve it, so many of us are vastly improving our working knowledge of various parts of RF, radios, software and electronics. Tom, wb6b |
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