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Re: Raduino CAD Files
Thanks everyone for the help!
Jerry, yes, I've been busy behind the scenes doing a lot of things with the control system. I now have the entire app running on an STM32F103 "Blue Pill" board, which is only about $2.50 on Ebay. This gives me a 70 mHz 32 bit controller with 128K bytes of program memory. My software S-meter is now working quite well and only requires 2 resistors and a cap, plus some code. I'm using a separate ILI7735 display for the S-meter, both displays on the same SPI bus. The S-meter is derived from a 10kHz sample-rate of the pre-amp audio, with software peak detection. The TFT meter display has a max-hold pointer that resets every few seconds, while the main pointer is real-time. There are digital readouts on it for peak signal level in uV, dBm and S-units. The measurements from the S-meter will drive a digipot after the audio pre-amp to effect a feedforward AGC. Feedforward, with software calibration, should make for a very fast acting AGC without the overshoot/undershoot artifacts of feedback systems. I'm also using a 400 ppr optical encoder for frequency control with interrupt processing; it tunes beautifully smooth, with 1 hZ steps and software acceleration. . All of this puts a real strain on the little Nano u-controller, hence the move to the Blue Pill. I intend to layout a new Raduino that accepts the 'pill', with extra connectors for SPI and I2C busses. I developed my own tinier version of the Adafruit Si5351 board that will mount on the Raduino. I might even use a separate Si5351 for the main VFO in order to eliminate the crosstalk spurs generated in the single-chip approach.?This was all moving smoothly while I was house-bound during Winter, but will slow down while the weather's nice outside. Joe W3JDR |
Re: Raduino not working 0 Volts on Pin 6 (red wire)
#ubitx-help
#ubitx
These might not apply to Rogier's issue, but since I have already typed this up, it may be still helpful to him or someone else.
I had 2 issues when trying to connect to the supplied Nano on the Raduino board to my Windows 10 machine. 1. USB connection.? ?I started with a cheap working cable (that I use with Segger J-link debugger boards all the time) and did not get a power connection. ? ? Fiddled around on a Friday evening, I am aware that the USB connector on the Nano clone board may be an issue. (socket + connector tolerance) ? ? With the right pressure from the thumb, I could get intermittent connection.? OK, making progress. ? ? Went through the stash box and found a 'better' (well at least more expensive) USB cable with ferrite chokes on either end, that made solid connection. 2. Driver. (nothing found on PC comport)? Well there had been some discussion of issues with Macs (that wasn't forefront in my mind at this time)? ? ?With hesitation, I downloaded a CH341 driver for Windows.?? ?(installation complained about not being successful, but the driver was working) Now I was up and running. Time for an adult? refreshment, sofa and bed. Project gets side tracked for other things.? When I get back to playing with the Nano clone,? What do I do?? Use my everyday cable. It doesn't work. Momentary lapse of sanity.? Get the 'better' cable and all is O.K. This was the first time I played with a Nano clone.? My only experience with Arduino is the Uno R3.? I use them often for adding quick instrumentation, remote pin control of hardware under test, etc. Clones are cheaper and make sense to use in various projects, like this one.?? However, If your budget allows, I'm an advocate of having at least 1 of the mainstream top tier manufactured products when you are self teaching. Having additional obstacles to overcome when your intent is to 'learn Arduino' can be frustrating.?? Regards, Gary |
Re: Low Power Output for Hendricks BitX20A - Watt meters and Scope readings do not agree....
#bitx20
The check would be you must be putting st least 2A into (24W to the finals, ~50% efficiency)
the finals to be in the 10-12W region. I don't ever believe scope readings as accurate. For power out I use a dummy load with a diode detector or a 30-40 db power attenuator as I have a calibrated unit 30db and 10db that into the spectrum analyzer gives good reading for power.? If all else fails if my 10W dummy gets hot its likely more than 10W.? The latter with a thermometer can be calibrated for power equal temperature using a variable power supply (DC power=RMS power). At some point you need an instrument you can believe. Allison |
Re: rough draft of how to connect BITX to PC for digital modes wiki
I found that there was too much attenuation in the ezdigi board so I use just the isolation transmformers and bipassed the rest. Mounted the board into the ubitx case and hardwired the ubitx side to a dpdt switch With the switch in one position it is in digital mode taking over control for the mic and speaker. In the other mode the radio runs normally ?Ran pig tails out to the desktop computer sound card. and keep the usb cable plugged into the computer. ?using the CEC firmware.
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#bitx40 #bitx40help bitx 40 Amateur radio kits world wide kit questions.
#bitx40
#bitx40help
A little background
I was given a bitx 40 for a gift from my brother. I'm a tinckerer? by nature so this makes sense. However, electronics are kind of new to me. Since this will be my first HF rig I opted to do a clean build. I ordered a model II case from amateur radio kits. The kit is cut to use a baofeng type ptt mic, the kit also has a gain control. It came with 10k pots x2, and a 100k pot. I. Not sure what pot goes where. I'm also not sure how to wire in the gain control. Can i get some guidance.? Thanks for the help. |
Re: A friendly suggestion for Farhan.
William Londree
Allison,
Thanks for your comments on small transmitting loops.? Seems to require a lot of work to get one working well. They are quiet on receive for sure but lots of Monkey Business to change frequency. Seems like an end fed vertical with an auto tuner might be more practical as a Stealth Antenna.? Just my 2 cents worth. Bill W6SDI |
Re: Low Power Output for Hendricks BitX20A - Watt meters and Scope readings do not agree....
#bitx20
Correction, 10x does not work, 1x does.
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10x would read double if that 9meg resistor inside the probe was more like 4meg. And that could easily be measured with an ohmmeter from probe tip to bnc center pin. On Thu, May 17, 2018 at 09:58 pm, Jerry Gaffke wrote:
And that since the 10x probe works, the scope is doing fine. |
Re: Low Power Output for Hendricks BitX20A - Watt meters and Scope readings do not agree....
#bitx20
Very weird, your math looks right to me.
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Could be a bad scope probe, have you tried more than one probe? Could be a bunch of bad scope probes. You have 4 measurements saying around 5 Watts and one saying 12 Watts. My bet is that it is around 5 Watts. And that since the 10x probe works, the scope is doing fine. If your scope is one that attempts to read the switch and scale the 1x vs 10x readings for you, could be that the?scaling feature is hosed. Not much going on in a scope probe: ? ?? In 1x mode, my cheapo scope probes show about 100 ohms from probe tip to BNC center pin, that 100 ohms might be there to prevent massive currents when I do something really stupid. In 10x mode, it's 8.9 meg. In both cases, it is almost certainly driving a 1 meg load inside the scope, just like the link above says. ? Would be interesting to replace your 1x probe with a short piece of coax. Or maybe just a twisted pair of hookup wire. Keep it below a meter in length to avoid trouble with reflections at 14mhz. Then try adding a 9meg series resistor, see if it behaves properly as a 10x probe. Jerry On Thu, May 17, 2018 at 09:13 pm, ab2ts wrote:
What am I missing? |
Re: rough draft of how to connect BITX to PC for digital modes wiki
Joe Puma
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On May 17, 2018, at 9:08 PM, atouk <atouk@...> wrote:
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Re: share your BITX success stories
Yup, I have no idea why they come mounted sticking out the side.
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If you wish, once flipped you can keep that LM7805 cool by soldering the tab to the Raduino ground plane, though somebody once pointed out that the heat will cause the 25mhz oscillator to drift a bit more. A 25 to 50 ohm 1/2 watt resistor, perhaps on the bottom of the uBitx, in series with? that 12v line into the Raduino will reduce the heat at the Raduino. On the Bitx40, it was necessary to add caps on that 12v line to keep LCD updates on the Raduino from getting into the 12v rail of the main board and creating hash in the receiver. I've added a diode on the Raduino board between the incoming 12v pin and the LM7805, after first cutting that trace.? Provides reverse polarity protection, which the LM7805 does not. Also, when powering the Raduino from the USB cable during downloads, that 5v goes back through the LM7805 and powers the radio, which is ok I guess if you want to? listen to the SW bands while downloading but seems it might cause trouble. On Thu, May 17, 2018 at 07:54 pm, ajparent1/KB1GMX wrote:
Flipped the 5V regulator around so it doesn't hang off, my case needed that bit of space for a really |
Re: Mic doesn't work in bitx40
#bitx40
I cant see any attachment. Just google and you will see what they look
like.
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Check your polarity of connection. At 17-05-18, you wrote: Thank you for your reply.. |
Re: uBitx diagnostic document from Facebook group
#ubitx
Thanks to?Ufi Auttorri for creating this guide. It was certainly a lot of work to do this.?
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Low Power Output for Hendricks BitX20A - Watt meters and Scope readings do not agree....
#bitx20
I solved my stability problem for the Hendricks Bitx20A ?kit by applying the?Martiens mod. ? ? Now I need to resolve a low power output problem. ? I had been just calculating the power output from my peak to peak O-Scope readings with a 10x probe. ? However I notice that while I had 70 VPP on the scope with the 10x probe ( ~ 12.2W = (70^2)/400 ); my wattmeters both read a much lower 4 to 6 watts. ? My wattmeters are a NorCal QRP Club watt meter and a Heathkit HM-9 QRP Wattmeter. ? I am driving the microphone input with a 600 Hz phase shift sine wave oscillator.
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Re: Raduino not working 0 Volts on Pin 6 (red wire)
#ubitx-help
#ubitx
I am (unfortunately) counting in from the right, so my pin numbering?
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is reversed from that shown at? ? On Thu, May 17, 2018 at 09:02 pm, Jerry Gaffke wrote:
I've got my uBitx Raduino totally unhooked from the wiring harness and the uBitx board, |
Re: Raduino not working 0 Volts on Pin 6 (red wire)
#ubitx-help
#ubitx
Yup, this one has been hard to follow.
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Let's keep this thread going, seems a fine title for it. Doing a search for "Rogier", I find these: /g/BITX20/message/47715 /g/BITX20/message/49091 /g/BITX20/message/49445 /g/BITX20/message/49496 /g/BITX20/message/49518 I'm assuming all his posts have been signed "Rogier". It seems he still has the original firmware installed, the Raduino worked at first,? but now it powers up with a display of "LSB A : 7150.000" and fails to respond to the function button or the encoder or the PTT switch. He also reports that? ? "There is 0 volt on pin 6 (red wire for the funktion button) to ground on the yellow wire (pin 4) or common ground on the chassis." His iMac does not see the Raduino when hooked up with a USB cable, but then? that's not unusual.? Many possible reasons for this. ? ########################### I've got my uBitx Raduino totally unhooked from the wiring harness and the uBitx board, laying flat on my desk.? Have a USB cable to a laptop to power up the Raduino. Using a corner mounting hole of the Raduino for ground, I see 4.6 volts on the first four pins in from the right on the top connector (ENCA, ENCB, FUNCTION, PTT). The 5'th is ground, so I see 0 volts there. The 6'th is 5 volts, and I see 4.7 or so because of a diode drop in the Nano. The 7'th and 8'th are analog pins without pullups, so are pretty much undefined. Be very careful when probing the 6'th pin that it does not get shorted to adjacent pins by the probe, but if you see around 4.7 volts there that will verify that the meter is set up correctly. If the Function button pin is low and the others high, could be there is something like a piece of wire or a glob of solder on the Raduino that is shorting it to ground.? With power off, how many ohms from the Function button pin to ground?? I see several mega-ohms. A shorted function button will put it into calibration mode, and it may be waiting for the function button to be released before updating the display. If all four of those pins on the right side are low, that suggests more serious trouble. Perhaps the flash program in the Nano got corrupted?? (I doubt it!) Perhaps the IO cells into the Nano got blown? (Not all four!) I'm betting the other three pins are high, and the Function button pin is getting shorted low somehow, and thus hanging up the processor. ? Jerry, KE7ER On Thu, May 17, 2018 at 07:37 pm, Gary Anderson wrote:
Rogier has a few threads open on his problems.? Casually, hard to keep up with where he is at the moment. |
Re: Mic doesn't work in bitx40
#bitx40
Thank you for your reply.. And the 1uF polar capacitor, also behaving weird. The positive side is show the same exactly voltage with the output from 4.7KOhm resistor. But the negative side always show 1.4Volt, even when the mic is connected or not. Please help me. Thank you |
Re: Asking for help solving a Hendricks kit BitX20 PA oscillation problem
I replaced both BS170¡¯s and solved the bias current problem. ??I re-soldered both T1 & T2. ??That may have been a contributor. ?I ended up using a 470 ohm resistor across their drains instead of the 1k resistor. ?Now all is very very stable. ???Currently trying to do a final alignment. ?Hoping that will fix my power output problem which is currently limited to about 4.2 Watts. |