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Re: I7SWX PTT Pop Mute

 

You might try taking the "+12V" of Gian's diagram from pin 8 of the LM386, which is only at 12v when the LM386 is powered up for receive.
I don't really know what all "+12V" into pin 7 might do, it certainly is not something written up in the datasheet.
But not much point in doing that when the LM386 is not otherwise powered up, which is the case during transmit.


On Fri, Jul 28, 2017 at 12:29 pm, Jerry Gaffke wrote:
I assume this is the circuit you are referring to: ?/g/BITX20/message/21876

Dumping 12v into the bypass pin of the LM386 to quiet it down is a bit unorthodox, but apparently works.
The LM386 does not have much of anything to do with transmit, hard to imagine why you are getting this result.
I suspect something else is going on.

Jerry
Re: Hey Jack!

 

Thanks for responding Jack. I thought you had a different group or site this stuff was coming from and shared here. I went back through my bookmarks and found the "Software controlled ham radio" Yahoo group. I haven't checked it in several months because the posts sound like a guys club with practically no focused content. Now it seems to have picked up a bit and saw your post about the Bitx 40 and a mag loop build. I almost talked myself out of it because of the cost of copper for a 40 meter band magnetic loop, which is between 17' and 34' in circumference. The plan was to have the mag loop for receive because of it's narrow bandwidth and noise rejection. And transmit with the low dipole that seems to be getting out better than originally expected. I just fell off topic too. Like I said, I thought this stuff was originally somewhere else. I also had plans to do something similar as the Forty-9er with another kit, but this BITX40 thing with the Raduino came along. Now I am feeling itchy for another project to play with. I'll go through the files section and your other group to collect everything in one spot. Thanks Jack.

I am including a link for a mag loop PDF because it seems like the definitive authority on the subject without talking over our heads. But still getting it all in there to explain it in detail. It might help someone curious about the magic antenna.
Re: Very fast post from India

chris gress
 

Still building my bitx60/80 waiting for parts mainly 10k pots bpf and lpf for 80m all done I can not wait to go portable with the radios?

On 18 Jul 2017 11:12, "chris gress" <Chrisg0wfh@...> wrote:
I got my 2x bitx 40 in 4 days much faster than DHL and no duty I have checked my 2 kits no damage to the main boards thanks :-)?


IMG_20170728_232930.jpg
IMG_20170728_225934.jpg
IMG_20170726_190104.jpg
IMG_20170726_190034.jpg

Re: Front End Protection Diodes?

 

Dale, are you using a 5MHz vfo? or have you changed to 19MHz and generate USB at 12MHz.
I note you have been using a spectrum analyser. Do you see any close in spurious outputs like in Tom Hurst's "BitX40 Spectrum Output" on page 2 of the files section?
For me, the 19Mhz is not a solution because the xtal filter is so bad on that side.
73 Brian.
Re: Hey Jack!

Jack Purdum
 

Hi John:

I guess that most of the discussion is around what I'm doing to the BITX40, which I call my B40. I'm selling a PCB for those mods which, when done, includes:

? ? B40 mods: TFT color display, rotary encoder tuning, CW mode, speech processor, AGC, contest keyer, S meter, and supply voltage monitor. You can see the custom PCB?
? ? ? ? ? ? ? ? ? ? ? ? in the Files section of the users group. Search "W8TEE" and then sort by most recent date and look for Rel03 of the assembly manual. I'm redoing the software?
????????????????????????'cus I'm not happy with the way it works right now. I hope to have a release soon that handles frequency tuning with Fast Tune, and the ability to change fields?
????????????????????????smoothly on the display. You can see the display in the Photos section under my call. I sell the board for $7.50 (domestic).

? ? Antenna Analyzer: The PCB is sold by qrpguys.com. With a bare junk box, it costs about $50 to build, but has some nice features. They also have the assembly manual that
? ? ? ? ? ? ? ? ? ? ? ? you can download to see what it does. This was supposed to be in the Sept., 2017, issue of QST, but I just got a notice about 10 days ago that it has been "bumped"?
? ? ? ? ? ? ? ? ? ? ? ? to a later issue. No mention of when that will be.

? ? Forty-9er: This was published in the March, 2016, issue of QST and is a $10 40M 3W CW transceiver to which we added an LCD display and VFO. The original xcvr was by ? ? ? ? ? ? ? ? ? ? ?????????????Wayne Burdick and Doug Hendricks and built as part of the NorCal QRP group back in the '90's. My goal was to make a frequency-agile xcvr that could be built for?
? ? ? ? ? ? ? ? ? ? ? ?under $50. The rig is pictured below:

Inline image
? ? ? ? ? ? ? ? ? ? ? ? This also used a custom PCB, which Farrukh Zia sells (www.farrukhzia.com/k2zia) for about $6.50.

Finally, some members here have mentioned two of my books: Beginning C for Arduino and Arduino Projects for Amateur Radio. The programming book is written for the true beginning programmer and assumes no prior programming experience. The second has a number of ham radio related projects using microcontrollers. You don't have to know programming to make the projects work and full source code is available for all projects at:?

????????https://www.mhprofessional.com/9780071834056-usa-arduino-projects-for-amateur-radio-group

Both books are available (and reviewed) on Amazon.com. You can click on the "Look Inside" banner on the book cover and read the Table of Contents and even some of the narrative.

I think that covers it.

Jack, W8TEE

From: John Smith via Groups.Io <johnlinux77@...>
To: [email protected]
Sent: Friday, July 28, 2017 2:23 PM
Subject: [BITX20] Hey Jack!

I have been coming to this site everyday and reading what's new, and little by little I see your other stuff creeping in. And was wondering if would post a link to your "other stuff" so I can get the full rundown on your for BITX40 DDS VFO, and the antenna analyzer, and so on. I am only getting pieces of it here, and would like to know more about it. I also wondered if you might be planning a book or something free with "Other stuff for the BITX'er". I can't just buy, I have to brew. And it's nice to find a funnel for all the information.


Re: I7SWX PTT Pop Mute

 

I assume this is the circuit you are referring to: ?/g/BITX20/message/21876

Dumping 12v into the bypass pin of the LM386 to quiet it down is a bit unorthodox, but apparently works.
The LM386 does not have much of anything to do with transmit, hard to imagine why you are getting this result.
I suspect something else is going on.

Jerry


On Fri, Jul 28, 2017 at 12:20 pm, KC8WBK wrote:
Unfortunately I have to withdraw my recommendation for this circuit, it is doing something odd to the transmit.
Re: I7SWX PTT Pop Mute

 

Unfortunately I have to withdraw my recommendation for this circuit, it is doing something odd to the transmit.? I am still using it, and have built three of the circuits to find out if it is my construction that is the problem or if it the circuit.? I am coming to the conclusion that the circuit is adding noise or carrier of some kind to the transmit signal.? I don't have a confirmation on this yet.
Re: Front End Protection Diodes?

Dale Brooks KG7SSB
 

The BITX40 vs3 is what I'm running and I purchased it about 2 or so months ago. I'm not sure what the older models require but I will say it really helped my rig to add the capacitor (100pf) to the L7 coil.? My second order harmonic (14Mhz) was only 12dbm lower than the primary frequency. To be in compliance with the FCC you should be 40dbm lower than the primary frequency or in this case 7Mhz band. To make matters worse the 3rd order component (21Mhz) was even more disturbing. Now with the addition of the capacitor across L7 I'm down -50dbm from the primary frequency including all spurious signals and well within FCC compliance. The person who started this thread had an attachment with full instructions showing where to place the diodes and the cap. Great hobby have fun! Dale Kg7ssb


On Fri, Jul 28, 2017 at 9:55 AM, David <dokrent@...> wrote:
I am a bit confused. I just recently bought the kit and from this thread I can't tell if you are referring to current or older units, or both. Seeking clarity.


Re: Hey Jack!

John P
 

I wish some moderator of this site could merge the millions of threads about Jack's VFO into one.
--
John - WA2FZW
Re: Changing IDE colors

John P
 

On Fri, Jul 28, 2017 at 09:41 am, <ckotan@...> wrote:
Does anyone have an OldEyesTheme.txt to share?
After making the changes to the font type, size and anti-aliasing that I mentioned in the other thread (Old Eyes), I personally found that the only thing I needed to change in the theme.txt file was the color for the /* . . .?*/ comments, which I just made the same as the // type comments. I have no trouble reading things now. But for what it's worth, here are my theme.txt and preferences.txt files:

--
John - WA2FZW

preferences.txt
preferences.txt
theme.txt
theme.txt

Hey Jack!

 

I have been coming to this site everyday and reading what's new, and little by little I see your other stuff creeping in. And was wondering if would post a link to your "other stuff" so I can get the full rundown on your for BITX40 DDS VFO, and the antenna analyzer, and so on. I am only getting pieces of it here, and would like to know more about it. I also wondered if you might be planning a book or something free with "Other stuff for the BITX'er". I can't just buy, I have to brew. And it's nice to find a funnel for all the information.
Re: Adding switchable USB and LSB to the Bitx40

 

I doubt you need a relay.
The two caps that get removed for USB operation (C91 and C92) can remain out for LSB operation as well.
Those caps are there only to allow the old analog VFO on the main Bitx40 to oscillate at 5 mhz.
Removing those caps allows the Si5351 on the Raduino to provide a 19mhz VFO signal to the Bitx40 for USB operation,
works just fine without the caps for the Raduino to supply 5mhz when operating LSB.

Most of us get by without a trimmer cap in the BFO to "clarify" the audio.
I suggest you evaluate the rig first, hack in that trimmer cap if you don't like how the audio sounds.
The trimmer in the BFO should affect receive audio and transmit audio in exactly the same manner.
The trimmer determines the frequency difference between the BFO carrier and the passband of the crystal filter,
which determines the range of audio frequencies that get received or transmitted.

The front end protection diodes are a good idea on currently shipped boards if you will ever
have the Bitx40 hooked up to an antenna while a nearby 100 watt rig is transmitting.
Without the protection diodes, all that would blow is the 2n3904 at Q13, which costs a few pennies.
(Though some might find the soldering job difficult on such a small part.)
.
There have been no changes to what gets shipped from hfsigs (hardware or firmware)
since the Raduino was introduced in Dec 2016.

Jerry, KE7ER


On Fri, Jul 28, 2017 at 09:54 am, David wrote:
I have received the kit just recently and I understand there are a few modes I can do, for example, adding two caps to the voltage regulator on the rardunio to prevent clicks, and one to improve mic clarity (perhaps a trimmer cap) as well as removing two caps to enable USB operation for digital modes. What I was considering was adding in a small solid state relay close to the board to enable me to easily switch from lsb to usb operation - adding or removing the caps using a dpdt relay. The relay would be controlled by a switch to the ardunio that would then toggle the relay and make the changes to the frequency calculation. Thoughts?
Re: LOOKING FOR HELP ADDING USB TO EXISTING BITX40 ARDUINO SKETCH

 

I made 2 functions and call them from the the usb / lsb case button (in bold)

It compiles and i can tune lsb but usb does not seem to work.

However, if i change th - to a plus in the if_offset - Usb seems to be there.

I


#ifdef IF_Offset
?uint32_t vco = bfo - (vfo * SI5351_FREQ_MULT);
?si5351.set_freq(vco, SI5351_CLK0); // WAS 0
?tbfo = "LSB";
?si5351.drive_strength(SI5351_CLK0,SI5351_DRIVE_8MA);?

#endif


I tried the other frequencies but they thru of the cal.


Joe
ve1bwv


buttonState3 = digitalRead(buttonPin3);
? if (buttonState3 != lastButtonState3) {
? ? if (buttonState3 == HIGH) {
? ? ? buttonPushCounter3++;
? ? ? switch (buttonPushCounter3) {
? ? ? ? case 1:
? ? ? ? ? Serial.println("USB");
? ? ? ? ? tft.setFont();
? ? ? ? ? tft.setTextSize(1);
? ? ? ? ? tft.fillRect(130, 225, 60, 15, GREY);
? ? ? ? ? tft.drawRect(130, 225, 60, 15, GREY);
? ? ? ? ? tft.setCursor(142, 229);
? ? ? ? ? tft.setTextColor(DARKGREY, GREY);
? ? ? ? ? tft.print("SSB/CW");
? ? ? ? ? delay(100);
? ? ? ? ? tft.fillRect(130, 225, 60, 15, DARKGREY);
? ? ? ? ? tft.drawRect(130, 225, 60, 15, GREY);
? ? ? ? ? tft.setCursor(142, 229);
? ? ? ? ? tft.setTextColor(WHITE, DARKGREY);
? ? ? ? ? tft.print("SSB/CW");
? ? ? ? ? delay(100);
? ? ? ? ? tft.fillRect(269, 130, 44, 18, BLACK);
? ? ? ? ? tft.setFont(&FreeSans9pt7b);
? ? ? ? ? tft.setTextSize(1);
? ? ? ? ? tft.setCursor(270, 145);
? ? ? ? ? tft.setTextColor(WHITE, BLACK);
? ? ? ? ? tft.println("USB");
? ? ? ? ? void usbjoe();

? ? ? ? ??
? ? ? ? ? break;
? ? ? ? case 2:
? ? ? ? ? Serial.println("CW");
? ? ? ? ? tft.setFont();
? ? ? ? ? tft.setTextSize(1);
? ? ? ? ? tft.fillRect(130, 225, 60, 15, GREY);
? ? ? ? ? tft.drawRect(130, 225, 60, 15, GREY);
? ? ? ? ? tft.setCursor(142, 229);
? ? ? ? ? tft.setTextColor(DARKGREY, GREY);
? ? ? ? ? tft.print("SSB/CW");
? ? ? ? ? delay(100);
? ? ? ? ? tft.fillRect(130, 225, 60, 15, DARKGREY);
? ? ? ? ? tft.drawRect(130, 225, 60, 15, GREY);
? ? ? ? ? tft.setCursor(142, 229);
? ? ? ? ? tft.setTextColor(WHITE, DARKGREY);
? ? ? ? ? tft.print("SSB/CW");
? ? ? ? ? tft.fillRect(269, 130, 44, 18, BLACK);
? ? ? ? ? tft.setFont(&FreeSans9pt7b);
? ? ? ? ? tft.setTextSize(1);
? ? ? ? ? tft.setCursor(270, 145);
? ? ? ? ? tft.setTextColor(WHITE, BLACK);
? ? ? ? ? tft.println("CW");
? ? ? ? ? break;
? ? ? ? case 3:
? ? ? ? ? Serial.println("LSB");
? ? ? ? ? tft.setFont();
? ? ? ? ? tft.setTextSize(1);
? ? ? ? ? tft.fillRect(130, 225, 60, 15, GREY);
? ? ? ? ? tft.drawRect(130, 225, 60, 15, GREY);
? ? ? ? ? tft.setCursor(142, 229);
? ? ? ? ? tft.setTextColor(DARKGREY, GREY);
? ? ? ? ? tft.print("SSB/CW");
? ? ? ? ? delay(100);
? ? ? ? ? tft.fillRect(130, 225, 60, 15, DARKGREY);
? ? ? ? ? tft.drawRect(130, 225, 60, 15, GREY);
? ? ? ? ? tft.setCursor(142, 229);
? ? ? ? ? tft.setTextColor(WHITE, DARKGREY);
? ? ? ? ? tft.print("SSB/CW");
? ? ? ? ? tft.fillRect(269, 130, 44, 18, BLACK);
? ? ? ? ? tft.setFont(&FreeSans9pt7b);
? ? ? ? ? tft.setTextSize(1);
? ? ? ? ? tft.setCursor(270, 145);
? ? ? ? ? tft.setTextColor(WHITE, BLACK);
? ? ? ? ? tft.println("LSB");
? ? ? ? ? ?void lsbjoe();
? ? ? ? ? buttonPushCounter3 = 0;
? ? ? ? ? // void lsbjoe();
? ? ? ? ? break;
? ? ? ? ??
? ? ? ? default:
? ? ? ? ? // if nothing else matches, do the default
? ? ? ? ? // default is optional
? ? ? ? ? break;








void lsbjoe(){
uint32_t vco = bfo - (vfo * SI5351_FREQ_MULT);
si5351.set_freq(vco, SI5351_CLK0);?
? tbfo = "LSB";
? volatile uint32_t LSB = 1199850000ULL;
? bfo = LSB;
? si5351.drive_strength(SI5351_CLK0,SI5351_DRIVE_8MA); //you can set this to 2MA, 4MA, 6MA or 8MA WAS CLK0
? return;
}

void usbjoe(){
uint32_t vco = bfo + (vfo * SI5351_FREQ_MULT);
si5351.set_freq(vco, SI5351_CLK0); // WAS 0
?
? tbfo = "USB";
? bfo = USB;
? volatile uint32_t USB = 1200150000ULL;
? si5351.drive_strength(SI5351_CLK0,SI5351_DRIVE_8MA); //you can set this to 2MA, 4MA, 6MA or 8MA?
? return;
}

On Fri, Jul 28, 2017 at 12:45 AM, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:
Looks like PD8W was written to drive the BFO with CLK0 from the Si5351 instead of using the Bitx40 analog BFO.
Though that is only activated if this line turns it on:
? ??#ifdef IF_Offset

My guess is that this never worked.

The PD8W code initializes the possible BFO frequencies in hundredths of a hz with these lines:

volatile uint32_t LSB = 1199850000ULL;
volatile uint32_t USB = 1200150000ULL;

The mistake I see is that the crystal filter is not centered on 12.000000mhz, it's more like 11.997000.
The value for LSB given above is correct if the VFO is operating down around 5mhz, the BFO is 1500 hz above the crystal filter center.
But the value for USB should be more like 11.995500 mhz, at 1500hz below the crystal filter center.

If the VFO is operating up at 19mhz, then we flip them so the BFO for USB is 11.9985 and for LSB is 11.9955 mhz.

If confused, read post ? ? /g/BITX20/message/24724
Note that I made the discussion easier to follow in post 24724 by assuming the filter is centered on 12.000mhz,?
but it is actually centered on something like 11.997000 mhz.

The filter uses the series resonant mode of the quartz crystals, and that series resonant mode is a few khz lower
in frequency than the parallel resonant mode marked on the the crystal as 12.000 mhz.
The analog bfo uses the crystal in the 12.000 mhz parallel resonant mode, that frequency is brought down a little bit by
adding capacitance.?

The Bitx40+Raduino as shipped does not have the Si5351's CLK0 driving the BFO,
that would require a hardware mod.? As shipped, only CLK2 of the Si5351 is used, to drive the VFO.

Jerry, KE7ER



On Thu, Jul 27, 2017 at 07:44 pm, Jerry Gaffke wrote:
I don't know anything about this PD8W code.
However, somewhere in the PD8W code it says:
? ??volatile uint32_t USB = 1200150000ULL;

That code you borrowed from Allard is treating the variable USB as a boolean,
so I assume Allard's version of the USB variable should have a value of either zero (false) or 1 (true):

if (USB) // if we are in UPPER side band mode
? ? si5351.set_freq((IF + Dial_freq) * 100ULL, SI5351_CLK2);
? else // if we are in LOWER side band mode
? ? si5351.set_freq((IF - Dial_freq) * 100ULL, SI5351_CLK2);//12-7 = 5


Re: Front End Protection Diodes?

David
 

I am a bit confused. I just recently bought the kit and from this thread I can't tell if you are referring to current or older units, or both. Seeking clarity.
Adding switchable USB and LSB to the Bitx40

David
 

I have received the kit just recently and I understand there are a few modes I can do, for example, adding two caps to the voltage regulator on the rardunio to prevent clicks, and one to improve mic clarity (perhaps a trimmer cap) as well as removing two caps to enable USB operation for digital modes. What I was considering was adding in a small solid state relay close to the board to enable me to easily switch from lsb to usb operation - adding or removing the caps using a dpdt relay. The relay would be controlled by a switch to the ardunio that would then toggle the relay and make the changes to the frequency calculation. Thoughts?
Re: Changing IDE colors

 

Does anyone have an OldEyesTheme.txt to share? I'd like to minimize experimenting with the color chooser.

Thanks all for this great thread. The Arduino IDE has been a pain in my eyes for years.

73, Charlie K?TAN
BITX QSO Night, Sunday, July 30, 7pm Local Time, 7277 kHz in North America, 7177 kHz elsewhere

 

BITX QSO Night, Sunday, July 30, 7pm Local Time, 7277 kHz in North America, 7177 kHz elsewhere

Join us as we make contacts from BITX40 to BITX40 on 7.277 MHz in 40 meters!

To participate, call CQ BITX at 7pm sharp, your local time, on Sunday. Call off and on for about 15 minutes. It is helpful if you call CQ BITX with your name and location.? Repeat your call a number of times if conditions are weak.

This is a worldwide event at 7pm in each time zone.? You may participate in any time zone, regardless of your location, so you may wish to call in at 6pm, 7pm and 8pm, your local time, to contact hams in adjacent time zones.

Report your QSO's, discuss propagation, noise, signal reports, audio reports, antenna type, etc. in this thread.

This is an undirected, scheduled event.? The BITX QSO Night relies on you to call CQ BITX to initiate contacts with other stations, so warm up that final and transmit a few calls at 7pm on Sunday.? Talk to you then!
Re: Front End Protection Diodes?

Dale Brooks KG7SSB
 

If you are installing 1n4148's across the antenna and ground you are just limiting the peaks, coming in on the antenna, to approx. .560 volts plus and minus.? If you use a germanium diode set you will limit the signals to .3 volts But you may get into trouble with strong signals limiting at this small voltage deviation causing distortion when the signal is clipping. Just a guess have not tested.?

On Thu, Jul 27, 2017 at 10:58 PM, Lawrence Galea <9h1avlaw@...> wrote:
That's the term we have been using for ages.
It means that one diode is placed with the cathode connected to one side of the circuit and the other connected the other way round so that they clip both sides of an AC voltage. (A DC voltage will also be clipped by the forward biased diode)
Taking the input of a receiver, one diode would have its cathode connected to the antenna input with the anode connected to earth. The other diode would have its anode connected to the antenna input and its cathode connected to earth.
Guess that different terms are used in different parts of the world.
Regards.



On Thu, Jul 27, 2017 at 9:53 PM, Dexter N Muir <dexy@...> wrote:
Back to back? I think not! That gives avalanche/breakdown voltage, and that can be up to kV depending on device. Try Head to tail - and across the input. +/-0.6V max, turn-on (forward-bias) voltage of silicon junction. 0.3V or so for germanium. If you're worried about capacitance, point-contact. This, of course is for RX ONLY! Tx into that will blow either the diodes or the Final! Not quite sure how it fits in the BITX scheme, probably in amongst the antenna relay circuitry.



Re: Front End Protection Diodes?

 

That's the term we have been using for ages.
It means that one diode is placed with the cathode connected to one side of the circuit and the other connected the other way round so that they clip both sides of an AC voltage. (A DC voltage will also be clipped by the forward biased diode)
Taking the input of a receiver, one diode would have its cathode connected to the antenna input with the anode connected to earth. The other diode would have its anode connected to the antenna input and its cathode connected to earth.
Guess that different terms are used in different parts of the world.
Regards.



On Thu, Jul 27, 2017 at 9:53 PM, Dexter N Muir <dexy@...> wrote:
Back to back? I think not! That gives avalanche/breakdown voltage, and that can be up to kV depending on device. Try Head to tail - and across the input. +/-0.6V max, turn-on (forward-bias) voltage of silicon junction. 0.3V or so for germanium. If you're worried about capacitance, point-contact. This, of course is for RX ONLY! Tx into that will blow either the diodes or the Final! Not quite sure how it fits in the BITX scheme, probably in amongst the antenna relay circuitry.


Re: Front End Protection Diodes?

Dale Brooks KG7SSB
 

I have been trying to reduce the 2nd and 3rd harmonics leaving the BITX40v3 for days and I just added the 100pf capacitor across L7 LPF coil and I will say it has solved all of my problems with higher than ideal harmonics. It is mentioned in the WAX articles along with the opposing diodes on the base of Q13. `My results on the spectrum analyzer was dramatic reducing all spurious signals well below 50 dbm. I have added the diodes as well as the100pf cap and recommend it for all BITX users.?

On Thu, Jul 27, 2017 at 2:10 PM, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:
1n4148's seem to work fine.
1n914's likely do as well, the Vishay datasheets look about the same.
Could be Vishay ships the exact same part.
The 1n914 is older, other manufacturers might spec a lower max forward current or something.?

"Back to back" and "front to tail" are both a ambiguous.
I suppose you could look at one of the drawings/photos previously posted.
? ??

Jerry

On Thu, Jul 27, 2017 at 01:44 pm, Mr Sheesh wrote:
I had been wondering if we were talking PIN diodes or what, 4148s


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