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?I only wish I could build the nice displays many of you did.

/g/BITX20/message/20449

?Thankfully, it's pretty easy to update the code for V2.

Here's the 'read me' info for the library: ?

Here's the info on the change: ?"The?set_freq()?method is now more streamlined and only requires two parameters: the desired output frequency (from 4 kHz to 150 MHz) and clock output. In your old code, you can delete the 2nd parameter in?set_freq(), which was the PLL frequency.?"

If you use a code-friendly editor like Notepad++, you can search for the instances of set_freq and delete the middle term (SI5351_PLL_FIXED)?and the code will likely compile with the V2 library.

That's all there is to it!

Andy

I will be sure to check out the analyzer when it comes out. By the time you guys get this bit of code organized where I can just copy and paste it in, I should be done putting mine in an enclosure. A basic black spray painted rectangle holiday tin. I used a nibbler for the LCD cutout and it looks a thousand times better than some others jagged Dremel cut outs.

I once killed a Uno by plugging in the USB cable while it was still plugged in to 12V. I knew better, but just didn't notice it first. I will be thinking about that when I upload the new sketch. And I do have a spare Nano.

Side note: Make it easy on yourself and change the pots for the knobs you have. On mine I thought I would be slick and use a 100K ?for nicer tuning. But nope, the higher resistance pot had a high resistance response on the incoming signal. No radio signals, just random birdies. Swapping it out to a smaller size diameter 10K pot put it back like it was with the original part.

So would a digital mode signal be any easier? Something connected to the mic input lines for rtty or psk31 perhaps

Well, conventionally PSK31 uses upper-sideband. If you've got an SI5351-based BitX, it's a fairly simple matter to change sidebands. I've forgotten what sideband is typically used for RTTY.

This question of using CW or any other mode than phone on the BitX can be addressed philosophically. At this price, one doesn't need a one-for-all-purposes rig. If one wants to also do CW, there's a number of excellent CW-only kits to carry on in the homebrew spirit. If one wants to get into scratch building, there's a bizillion tried-and-true designs with long histories and broad-based support available in the Ham community.

73,

Todd K7TFC?

Well, that's what I was afraid of. It is like trying to make milk from chalk and water, you're going to need a lot more than what you got. In other words, it's impractical.?

I would need proper instructions with a picture and a schematic to pull it off.

So would a digital mode signal be any easier? Something connected to the mic input lines for rtty or psk31 perhaps.

And as for a test tone for tuning an antenna tuner, could a simple sine wave generator circuit inject a signal into the mic input? Does anyone know what kind of power ratings there are for the mic circuit? Some CPO circuits can be loud until you put a resistor on the speaker line.

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Whoops, had a copy-and-paste error. ?That first line should be: ? ?pinMode(4, OUTPUT);

Also, while that first line is typically in the ?setup() ?routine, the other three lines could be most anywhere, and need not be together.

Allison's comments are probably worth chasing a little further. ?Here's a summary of her points, and my comments:

1) ?Diode ring injection level should be higher for the 1n4148's

Likely true. ?An easy fix is to move from 1n4148's to a couple BAT54S's in that DBM. ?Perhaps even try a commercial DBM here if you really know what you want. ?And/or adjust the injection level. ?All easily done.

2) ?DBM wants ports at 50 ohms for better overload and IMD performance

Probably true. ?But 200 ohms works well for feeding the crystal filter, and does reduce power consumed. ?Somebody with the W7ZOI 50 ohm amps might patch them in and feed the filter appropriately, see if the improvement is worthwhile. ?Could be that much of this preference for 50 ohms is because it's a nice standard impedance to look at and test with, and not so much driven by performance. ?

3) ?Recommends diplexer between DBM and crystal filter

One of those things that adds parts and complexity, may well reduce spurious received signals. ?But we seem to have identified all the images and birdies thus far, perhaps this doesn't add much to performance. ?Would be worth trying, do an A/B comparison.

4) ?Too much RF gain

Don Cantrell has a nice hack for this, just shut down power to Q1. ?Though some gain at Q1 might prove useful in some cases. ?Alternately, put a pot on the rx signal between the relays. ? ?If we reduce RF gain we need to increase AF gain, and that will result in greater sensitivity to power supply noise. ?

5) ?Move VFO to high side of IF to reduce images.

Yup. ? My Si5351 VFO will be up around 19mhz, just a matter of Raduino code and moving the BFO a couple khz.

A few other things I'm keeping in mind:

6) ?Q13 can blow, either from a nearby transmitter or from too much power dissipation for a Sot23. ?Use a TO92 there? ?Add Raj's back-to-back diodes?

7) ?Q14 emitter resistor can burn out, find a bigger part?

8) ?Might want Raj's fractional ohm source resistor to protect the IRF510. ?My guess is it's not often seen in an RF power amp because on standard RF transistors the source is attached to the tab which gets grounded to the heat sink. ?Not true with the IRF510. ?Maybe a PolySwitch to limit current.

9) ?Add minor hardware bits needed to support CW, maybe standalone PSK31

10) ?Add features for easy testing.

Jerry, KE7ER

John Smith,

Regarding noTone()

Pin 6 is used in the Raduino sketch for "CW_TONE", Ashhar has it set up to send out a sidetone. ?Probably best to let pin 6 be, pin 4 is free though, it gets defined as "TX_LPF_SEL" but that define is never used. ?I tried my code snippet, the compile complained until noTone() was given a pin number to shut down, even though the library can only generate one tone at a time. ?So working code could be had by adding this anywhere inside the setup() routine in the Raduino sketch, including right at the top as shown here

########################

void setup()

{

? ? inMode(4, OUTPUT);

? ? tone(4, 1000);

? ? delay(5000);

? ? noTone(4);

########################

Note that "4" is labeled as "D4" in the Raduino schematics, and is more a name than a number. ?It is actually pin 22 of the Nano. ? The Nano has pin names 0 through 12, though 8,9,10,11,12 are used by the LiquidCrystal library for the 2x16 LCD. ? These are all strictly digital pins, can be input or output, but have states of only high or low. ?The Nano also has pin names A0 through A7, though A4,A5 are used inside the Si5351 library. ?These can be analog inputs to the ADC (such as for reading the the voltage of that tuning pot), or can be used as digital pins.?

If you plan to mess around with Arduino programming, probably a good idea to get another Nano or two. ?They are quite cheap, and it is possible to program them in such a way that they will no longer talk to you. ?Probably don't want to brick the Nano that came with the Raduino.

Jerry

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Modulated CW (MCW) originally was a AM tone. So you had carrier plus both side-bands.? Receivable on ordinary am receiver.