Phil
Welcome to the worldwide community. Let's see you need some kind of microphone,? a suitable power supply, and a good 40m antenna.
Put it on the air once? Glad you have it so it can be used many times. We can debate a good 40m antenna, but something like a half wave dipole can bring many contacts.
Use the rig before you decide if it needs anything more. Yes they can be modified to use on other bands. I will relate that its easier to make low power ssb contacts on 40m rather than 80m.
Curt
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Re: Balanced Mixer Audio Input Impedance
Apparently, I was a lot smarter two years ago. Here's a brief description of how that modulator "multiplies" to get sum and difference frequencies: ? ?? /g/BITX20/message/22530The rest of that old thread might be worth reviewing as well. Jerry, KE7ER
On Thu, Mar 14, 2019 at 08:21 AM, Jerry Gaffke wrote:
Here is Tom's key insight:
> The RF envelope of the transmitter modulated by the sideband modulator is
> almost like what the audio fed (through) a full wave rectifier would look like.
> The big difference is the phase of the RF carrier will be the opposite
> for the positive and negative parts of the audio waveform cycle. ?
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Re: New V5 with poor carrier suppression.
When I read this thread with the comments about the diodes being open, shorted, or improper bias, and having had an issue with the D5 diode(s) prior, I got to thinking I should test D5 to verify that that was not the cause of my BFO needing adjustment (post #66111).? The most accurate test would be to remove it from the circuit and test.? As my SMD skills are still under development, I did not want to go that route.? I then came up with using a scope to measure the 12MHz signal into the diodes, and then the result at the output.
What I believe you should see (as I did) is the square wave (with ringing) on pins 1 and 2 of D5, and no (or very minimal) signal on pin 3.? That would be testing the diodes and T7 for proper operation.? I did this on both transmit and receive, seeing the same results when connected to a dummy load and no audio in on transmit.
The above process may be obvious to most, however it was not to me, so I am sharing in case someone else questions their BFO mixer prior to adjusting the frequency to reduce the carrier and is unaware of how to test in circuit.
If the process is not accurate, please comment back so that I can better understand.
73
Evan
AC9TU
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Re: #bitx40 Display questions
#bitx40
Mike,
That's what you get when the display is powered up but it receives no commands from the Nano.
Take a hard look at page 7 of the datasheet for your LCD that you posted previously in this thread.
Pin numbering on that 16 pin connector is very very strange!
Pin 14 is at the corner of the LCD board, and counts down from there to the square pin 1.
After pin 1, we have pins 16 and 15, in that order.
Pin 15 is on the outside edge of the connector, and would normally get grounded by the Raduino,
pin 16 is one pin in and the Raduino gives it 5v for the backlight.??
By default, this would mean your backlight should not turn on, but the jumpers on page 8
show how those two pins can be swapped.
Wow!
I have never seen such a screwed up connector pin-out.
Smells like somebody laid the board out without a hard look at what everybody else was doing,
then adjusted the documentation as inconspicuously as possible to agree with common pin numbering.
But that sort of crap should be in big red letters at the top of page one of the documentation,
not hidden away in a barely understandable mechanical drawing..
You have probably also given pin 14 a ground, and pin 13 +5v.
Those are both data lines into the LCD, and happen to be two of the four bits that need to work.
I'm guessing that the LCD controller chip survived this, but I could be wrong.
Be sure to complain mightily to the vendor.
Give a review that warns others of this major botch if you can.
Jerry, KE7ER
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On Sun, Mar 17, 2019 at 09:12 AM, Mike Short wrote:
Here is what is displayed. When I connect the display that comes with the radio, works fine.
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I purchased an assembled Bitx40 from another local ham.? He stated that he had assembled the kit, put it on the air once and then bought a uBitx.
I have seen numerous discussions here about modifications and operating the radio.?
I'm looking for any suggestions to use this radio on the air.? I would like to use it as a portable rig and possibly operating on 80M.
Thanks in? advance,
Phil KC2YLM?
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Re: #bitx40 Display questions
#bitx40
Here is what is displayed. When I connect the display that comes with the radio, works fine.
On Sun, Mar 17, 2019 at 10:27 AM Mark - N7EKU < n7eku@...> wrote: Hi,
Maybe you've got it backwards -- I think the backlight will work even when hooked up in reverse because of the way the power is wired on pins 1 & 2 and on 15 & 16?
73,
Mark.
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Re: #bitx40 Display questions
#bitx40
Hi,
Maybe you've got it backwards -- I think the backlight will work even when hooked up in reverse because of the way the power is wired on pins 1 & 2 and on 15 & 16?
73,
Mark.
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Re: Saving V5 Default Calibration file and sharing
Same.? It seems wise to always have a fallback point at the ready, maybe even stored in a spare Uno board for quick change or diagnostic type stuff (or the zombie apocalypse, whatever).?
Ted
K3RTA
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Re: #bitx40 Display questions
#bitx40
I now only have one row displaying. I guess the display is bad.? ?My comment on solid dots is all dots for each character illuminated like it does on power on.
Mike
On Sat, Mar 16, 2019 at 10:27 AM Jerry Gaffke via Groups.Io <jgaffke= [email protected]> wrote: Looks like your display has the same HD44780 control chip as the stock Raduino has.
And the 16 pins described in your datasheet line up nicely with the 16 pins in the Raduino schematic,
so should just plug in.? Double check that RS (register select, not reset) on pin 4 of your LCD
is connected to pin 4 (D8) on the Raduino, so the connector is not flipped around somehow.
Note that the "Write" pin is permanantly grounded, we never have reason to read the LCD.
The LCD is used in 4 bit mode, so data bits D0,1,2,3 are not needed.
What do you mean by "displaying solid dots"???
A blown Nano or LCD tends to power up with one of the two rows of characters being black rectangles,
so maybe something is simply not working for you.? Perhaps it is simply a defective LCD?
There's a small pot on the Raduino to adjust the LCD contrast, try twiddling that pot, see if that helps.
Try plugging the stock LCD back into the Raduino, verify that it still works properly.
> Confirming what Mike is saying, the 16x2 parallel LCD display attaches to the header on the opposite side
> of the Raduino board from the connectors shown in the wire up diagram.
The wire-up diagram at the top of this webpage:
? ? ??
is not a photograph, it is generated by the board routing software and does not?
realistically show all the parts on the boards.
In particular, the 16 pin connector for the LCD is not in the image, it should be
sticking out of the top left of that image.? The LCD plugs into this side of the
Raduino,? ?The bottom 5 pin connector (with the "DDS" wires) is on the back.
Jerry, KE7ER
On Sat, Mar 16, 2019 at 06:15 AM, Mike Short wrote:
I got that. I am using a larger 16x2 display.?
What i can¡¯t figure out is what data pins on the ?Raduino go to?
which ones on the larger display. I attached the datasheet to the original post. ?
It is powered on and the backlight works fine.
It is displaying solid dots.
The display that came with the kit works fine.
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Many good suggestions.?
The quick way is to simply bolt on a small fender washer or even a ring terminal with the wire-end widened out flat.? In the end, remember that the 58xx are rated to operate just fine at temps warmer than most people want to touch, so, unless one is getting burned or the device is shutting down due to overload, I wouldn't worry too much.?
That said, A 1 x 2 cm strip of steel (think: PC expansion slot cover) is enough to take the edge off and feel more comfortable about it.
Ted K3RTA
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Hi,
You can add a resistor if you want, but you need to know what current the display consumes because you don't want to drop too much voltage through the resistance.? Different 2-line LCD's will consume different current depending on their backlight type.? I imagine the Nexion displays also vary a lot in what they consume.? I would just put a TO-200 heatsink on the regulator and it should be fine with that.? Too much current through a resistor can cause other problems too (e.g. needs to be sized by wattage appropriately)!
73,
Mark.
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I would agree with Raj.? Add a heat sink and use as is IF you are not planning any significant mods to the stock rig.
I did add a series resistor to my first uBitx v4 by lifting the input on the 7805 from the board and wired it in leaving the other two leads soldered to the Raduino.? The resistor lays flat against the board, one lead in the hole vacated by the 7805 input pin and the other connected to the input pin.
After doing the above, the regulator was much cooler.? However I would only go through the trouble on one of two conditions:
1 - If you are going to run with the input higher than 12.5 vdc to the main board (doesn't matter the voltage to the PA).
2 - If you are going to add a significant load to the 5 volt regulator in the form of another Nano or larger display.
Since I have already installed a 2.4" Nextion display and Dr. Lee's CEC software, and I want to add the standalone signal analyzer, I made the mod.
Above is my experience and opinion.? Yours may vary.?
73
Evan
AC9TU
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I was troubleshooting something I forget rather early, and discovered that hot regulator and thought I may have fried something it fed. Fortunately someone here had months of ubitx experience.?
These regulators are designed for warmth. I imagine someone has researched how close we are to its thermal recommended margin. Yet who has ever had one fail. The dissipation has to go someplace, and many watt resistors aren't cheap. Best to keep it like this.
Curt
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Find the 12V connection to the regulator and add another regulator between the 12V supply and the 7805 regulator. A 7809 or 7808 mounted on the metal case would be fine. Add a 1¦Ìf, 100nf and 10nf capacitors in parallel at the output of the 7809 or 7808 regulator and similar capacitors at its input. This splits the drop between the regulators.
A resistor is cheaper but regulators cost only a few cents. You can also mount the 7805 on the metal case. Regards
A small heat sink like the finals or a small metal plate to increase the heat dissipation
can be repurposed from some junk..
I just let them cook and curse when I burn my fingers on the Raduino!
Raj
At 17-03-19, you wrote:
>Just starting to wire up my v5 uBitX and trying to solve problems ahead of time.? I would very much like to install a series resistor to lighten the work of the Raduino 5V regulator, but can't for the life of me see where it can be easily done (that is, without cutting traces, etc).? I have looked through most of the documentation and forum entries but haven't found any details.? Could someone point me in the right direction as to how this can be physically done?? If it can't be easily accomplished, given my 70+ year old fingers and eyes, I will have to settle for just a heat sink.? (Which might not be a bad idea anyway, HI)? Many thanks.
>... Martin? ?VE3OAT
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A small heat sink like the finals or a small metal plate to increase the heat dissipation
can be repurposed from some junk..
I just let them cook and curse when I burn my fingers on the Raduino!
Raj
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At 17-03-19, you wrote: Just starting to wire up my v5 uBitX and trying to solve problems ahead of time. I would very much like to install a series resistor to lighten the work of the Raduino 5V regulator, but can't for the life of me see where it can be easily done (that is, without cutting traces, etc). I have looked through most of the documentation and forum entries but haven't found any details. Could someone point me in the right direction as to how this can be physically done? If it can't be easily accomplished, given my 70+ year old fingers and eyes, I will have to settle for just a heat sink. (Which might not be a bad idea anyway, HI) Many thanks.
... Martin VE3OAT
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I should also have mentioned that??Pocket RxTx works perfectly with the uBitx when connected to the Raduino Nano USB port with no modifications needed to the uBitx.
73 Bob GM4CID
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Ray,
Another possibility is to use the app Pocket RxTx available from the Google Play Store at
.
Pocket RxTx?doesn't need a lot of horsepower so?will work with an older (or current) Android phone or tablet that can use?an OTG cable.
Connection is USB so a normal Yaesu CAT cable is needed or can be by bluetooth with a special adapter plugged into the back of the rig.
73, Bob GM4CID
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Hi Bob:
Can I make the payment through Paypal?
can use QRZ address to contact directly with me
LuisM
EB4EPY
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I think mine for the 817 is this one.
Valley Enterprises? Yaesu USB FTDI CT-62 CAT Cable FT-100, FT-817, FT-857, FT-897
Ray
We have all these display options for bitx rigs because of generous folk who do the programming,? and the open source of the design. With ft817 you must do surgery in hardware and software, it just isn't made for that. I see Laurence has a wonderful idea, use a PC interface.
BTW there is a nice, cheap enough, third party interface to USB out there. Reminds me I should get one, if they are still sold.
73 curt
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Ted
Raj vu2zap