Date   
rough draft of how to connect BITX to PC for digital modes wiki

Doug W
 

It seems almost every day (or hour) someone has a question about connecting their radio for digital modes.  Following are my cobbled together notes that if the group deems worthy could be the start of a wiki page on the topic.  My concern is my use of a TRRS jack might be too specific, but at least this is a place to start.  Your feedback is welcome.

----------------

There are many different ways to pair your radio’s audio and ptt circuits with a computer to work digital modes.  This is not a discussion of all the different ways.  This is how I did it.  Most of the information is readily available if you search this list and online.

I'm using an Easy Digi kit for switching PTT and isolating Rx audio.  I found the loss was too high on the Tx side so I'm going right from the sound card to the rig for Tx but I will describe using both sides of the Easy Digi below.  I set up my radios with a mono jack for the speaker and TRRS for mic/PTT and corresponding cables on the Easy Digi so everything is interchangeable.  I'm using a USB sound card and an FTDI cable.  I have the sound card and FTDI cable plugged into a small unpowered USB hub with the Easy Digi hot glued on top with the cables all hot glued for strain relief.  It is ugly as sin but sits out of sight and works.  There are links below to all the parts I used.

Pop the cover off the USB sound card and desolder the two audio jacks.  Cut two pieces long enough to go from the sound card to the Easy Digi off the mono cable.  It is 6’ long, you have plenty to spare and it is good shielded cable.  Solder the cables where the jacks were and route them out the holes in the case where the jacks were.  Now solder those cables to the corresponding spots on the Easy Digi.  Mic from the sound card to Audio to PC on the Easy Digi and speaker on the sound card to Audio from PC.  Now solder the audio cable with plugs to the Easy Digi board.  Audio to your radio’s speaker via the mono cable and Mic to your radio’s mic via the 4 conductor cable if doing it like I did.  The last connections are from the FTDI to the Easy Digi and the Easy Digi to your ptt.  Cut the RJ45 connector off the FTDI cable and connect the following cables to the Easy Digi, Black to DIG GND, Green to DTR and Brown to RTS.  Those are the only wires you will use in that cable.  Now connect PTT HI on the Easy Digi to your PTT wire and PTT GND to your PTT ground.  Both of these are also part of the 4 conductor cable.  Now plug the FTDI cable and USB sound card in the USB hub and connect the hub to your computer.  If you are using Windows, your machine should set both up without issue.  Connect the mono jack to your radio's speaker jack and the TRRS plug to your TRRS jack or however you have your mic and ptt connected.

Assuming you are using WSJT-X, in settings under the radio tab select RTS for PTT method and whatever port the FTDI adapter cable shows up on.  With a dummy load connected to your radio click the Test PTT button several times to make sure it toggles Tx on and off on your radio.

One last very important thing.  The heat sinks on the IRF510’s are sized for casual voice and cw work not the full blast usage of digital modes.  Make sure you have a plan to deal with the heat.  There are many other posts on heat sink ideas.  I have found even a little air flow from a small fan makes a huge difference.


Following are the parts I used:

 

Easy Digi

https://www.ebay.com/itm/322873075639


mono cable with plug

https://www.digikey.com/product-detail/en/tensility-international-corp/10-00344/839-1039-ND/2350247


4 conductor cable with TRRS plug

https://www.digikey.com/product-detail/en/tensility-international-corp/10-00341/839-1036-ND/2350244


TRRS jack

https://www.jameco.com/z/PJ31640-3-5mm-4-Conductor-TRRS-Panel-Mount-Phone-Jack_2201607.html


USB sound card

https://www.banggood.com/External-USB-2_0-for-3D-Virtual-Audio-Sound-Card-Adapter-Converter-5_1CH-p-1011122.html


FTDI cable (do not buy a cheap TTL adaptor, they do not put out high enough voltage for the opto coupler on the Easy Digi)

https://www.banggood.com/External-USB-2_0-for-3D-Virtual-Audio-Sound-Card-Adapter-Converter-5_1CH-p-1011122.html


USB hub

https://www.amazon.com/gp/product/B01MSJBXU1


I found this breakout jack helpful for confirming the wires on the 4 conductor cable before soldering up the TRRS jack

https://www.amazon.com/gp/product/B01J4G00MI


--
Doug
AC9RZ
www.bitxmap.com

Re: Using the uBitx with FT8

Doug W
 

I just posted how I did it.  There are many other ways but this should get you started.  https://groups.io/g/BITX20/message/49561
--
www.bitxmap.com

Re: ND6T AGC implementation for uBIT-X

Kees T
 

Jerry,  

Re: uBITX Wireup Diagrams on the HF SIGNALS WEBSITE ARE WRONG!! #ubitx #ubitx-help

Alan Shapiro
 

How can the plugged in paddle work when only the tip (or ring) and ground of course,are connected?  Don't both tip and ring have to be wired?  What am I missing?

Re: rough draft of how to connect BITX to PC for digital modes wiki

atouk
 

I followed a similar approach.  Mounted a 4 port usb hub inside the case.  One port for the radiuno, one for a 6 buck usb sound dongle, two free for future use (rtl dongle for panadapter and maybe a pi0 for for something in the future).

I also used an Easy-Digi board simply because I prefer to have the radio as electrically isolated from the computer as possible.  The advantage of the USB sound dongle is that the radio gets it's own dedicated audio in and out channels. This way I can have WSJT-X running and not lose my main PC audio.   Disadvantage?  I used an unpowered hub that puts a load on a single USB port with the RTL dongle plugged in.  I'll change that later.

The only thing I had to do to tame the audio is to put a 330 ohm resistor across the output side of the audio out (dongle mic in) to make the volume adjustment smoother.

I run the CEC software to control freq changes and transmit from WSJT-X via CAT control through Onmi-Rig.


On 5/17/2018 8:45 PM, Doug W wrote:
It seems almost every day (or hour) someone has a question about connecting their radio for digital modes.  Following are my cobbled together notes that if the group deems worthy could be the start of a wiki page on the topic.  My concern is my use of a TRRS jack might be too specific, but at least this is a place to start.  Your feedback is welcome.

----------------

There are many different ways to pair your radio’s audio and ptt circuits with a computer to work digital modes.  This is not a discussion of all the different ways.  This is how I did it.  Most of the information is readily available if you search this list and online.

I'm using an Easy Digi kit for switching PTT and isolating Rx audio.  I found the loss was too high on the Tx side so I'm going right from the sound card to the rig for Tx but I will describe using both sides of the Easy Digi below.  I set up my radios with a mono jack for the speaker and TRRS for mic/PTT and corresponding cables on the Easy Digi so everything is interchangeable.  I'm using a USB sound card and an FTDI cable.  I have the sound card and FTDI cable plugged into a small unpowered USB hub with the Easy Digi hot glued on top with the cables all hot glued for strain relief.  It is ugly as sin but sits out of sight and works.  There are links below to all the parts I used.

Pop the cover off the USB sound card and desolder the two audio jacks.  Cut two pieces long enough to go from the sound card to the Easy Digi off the mono cable.  It is 6’ long, you have plenty to spare and it is good shielded cable.  Solder the cables where the jacks were and route them out the holes in the case where the jacks were.  Now solder those cables to the corresponding spots on the Easy Digi.  Mic from the sound card to Audio to PC on the Easy Digi and speaker on the sound card to Audio from PC.  Now solder the audio cable with plugs to the Easy Digi board.  Audio to your radio’s speaker via the mono cable and Mic to your radio’s mic via the 4 conductor cable if doing it like I did.  The last connections are from the FTDI to the Easy Digi and the Easy Digi to your ptt.  Cut the RJ45 connector off the FTDI cable and connect the following cables to the Easy Digi, Black to DIG GND, Green to DTR and Brown to RTS.  Those are the only wires you will use in that cable.  Now connect PTT HI on the Easy Digi to your PTT wire and PTT GND to your PTT ground.  Both of these are also part of the 4 conductor cable.  Now plug the FTDI cable and USB sound card in the USB hub and connect the hub to your computer.  If you are using Windows, your machine should set both up without issue.  Connect the mono jack to your radio's speaker jack and the TRRS plug to your TRRS jack or however you have your mic and ptt connected.

Assuming you are using WSJT-X, in settings under the radio tab select RTS for PTT method and whatever port the FTDI adapter cable shows up on.  With a dummy load connected to your radio click the Test PTT button several times to make sure it toggles Tx on and off on your radio.

One last very important thing.  The heat sinks on the IRF510’s are sized for casual voice and cw work not the full blast usage of digital modes.  Make sure you have a plan to deal with the heat.  There are many other posts on heat sink ideas.  I have found even a little air flow from a small fan makes a huge difference.


Following are the parts I used:

 

Easy Digi

https://www.ebay.com/itm/322873075639


mono cable with plug

https://www.digikey.com/product-detail/en/tensility-international-corp/10-00344/839-1039-ND/2350247


4 conductor cable with TRRS plug

https://www.digikey.com/product-detail/en/tensility-international-corp/10-00341/839-1036-ND/2350244


TRRS jack

https://www.jameco.com/z/PJ31640-3-5mm-4-Conductor-TRRS-Panel-Mount-Phone-Jack_2201607.html


USB sound card

https://www.banggood.com/External-USB-2_0-for-3D-Virtual-Audio-Sound-Card-Adapter-Converter-5_1CH-p-1011122.html


FTDI cable (do not buy a cheap TTL adaptor, they do not put out high enough voltage for the opto coupler on the Easy Digi)

https://www.banggood.com/External-USB-2_0-for-3D-Virtual-Audio-Sound-Card-Adapter-Converter-5_1CH-p-1011122.html


USB hub

https://www.amazon.com/gp/product/B01MSJBXU1


I found this breakout jack helpful for confirming the wires on the 4 conductor cable before soldering up the TRRS jack

https://www.amazon.com/gp/product/B01J4G00MI


--
Doug
AC9RZ
www.bitxmap.com

Re: Using the uBitx with FT8

Roy Appleton
 

By the way, thanks Doug for taking the time to post your work on doing this. I'll very interested in doing the same thing!

Roy
WA0YMH

On Thu, May 17, 2018, 7:46 PM Doug W <dougwilner@...> wrote:
I just posted how I did it.  There are many other ways but this should get you started.  https://groups.io/g/BITX20/message/49561
--
www.bitxmap.com

Re: A friendly suggestion for Farhan.

John Smith
 

I made a mag loop for 40 and am working on the homemade capacitors remote tuning mechanism. I started with an arduino and servo, and now going KISS with a DC 0.6 RPM motor, momentary rocker switch, PWM driver to slow it down more, and a field strength meter to use instead of a SWR meter. I once said before the uBITX was released I wouldn't mind assembling and winding the toroids myself like other kits are. And I too stock parts. Woodworkers stock wood, machinists stock metal, we all stock things for our hobbies as we chose to enjoy it. It's an investment in our continued enjoyment, as well as a convenience. Who likes to wait 6 weeks to start a project?

Re: ND6T AGC implementation for uBIT-X

Jerry Gaffke
 

Yup, that would work.
I'm thinking of something useful for detecting low level RF when trying to figure out why the transmitter is putting out 1 Watt instead of 5Watts.
But the scaling resistors in front of your AD8307 could be adjusted as needed.

I was also thinking that if the AGC or pop fix boards needed to be redone, you might squeeze in pads for an AD8307.

Nik has an AD8307 on his Raduino:
   https://groups.io/g/BITX20/message/42237
Did anyone try it?
Was it quiet enough to be useful?

Jerry, KE7ER



On Thu, May 17, 2018 at 05:54 pm, Kees T wrote:
Jerry,  

Re: uBITX Wireup Diagrams on the HF SIGNALS WEBSITE ARE WRONG!! #ubitx #ubitx-help

Jerry Gaffke
 

What you are missing are some resistors plus these comments from the Raduino source code file  ubitx_keyer.ino:

* CW Keyer
 *
 * The CW keyer handles either a straight key or an iambic / paddle key.
 * They all use just one analog input line. This is how it works.
 * The analog line has the internal pull-up resistor enabled.
 * When a straight key is connected, it shorts the pull-up resistor, analog input is 0 volts
 * When a paddle is connected, the dot and the dash are connected to the analog pin through
 * a 10K and a 2.2K resistors. These produce a 4v and a 2v input to the analog pins.
 * So, the readings are as follows :
 * 0v - straight key
 * 1-2.5 v - paddle dot
 * 2.5 to 4.5 v - paddle dash
 * 2.0 to 0.5 v - dot and dash pressed
 *
 * The keyer is written to transparently handle all these cases
 *

So there is one wire into the Raduino, but the voltage on that single wire
says if you have nothing going on, the straight key is pressed, or the dot or dash paddles are pressed.
Very clever.

Unfortunately, it doesn't work very well.  A little bit of dirt in your straight key contacts and the
resistance there can be enough that the Raduino things it's a dot paddle press.

Here's a hardware fix, your key tells a fet to turn on, which in turn switches the resistor network:
    https://qrpguys.com/ubitx-cw-conditioning-adapter
Some of the newer firmware releases have ways around this problem also.  

Jerry, KE7ER



On Thu, May 17, 2018 at 06:02 pm, Alan Shapiro wrote:
How can the plugged in paddle work when only the tip (or ring) and ground of course,are connected?  Don't both tip and ring have to be wired?  What am I missing?

Re: Raduino Questions for Bitx40

Ashhar Farhan
 

Then board seems alright. It looks like some raduino wire is grounded that shouldnt be grounded. Check your wiring carefully against the wiring diagram at HF Signals.

- f

On Fri, 18 May 2018, 04:04 Thomas Erwin, <terwin3486@...> wrote:
Greeting,
If I may I have a few questions about my Bitx40.  My display will only on power up will show "Raduino v1.01 and will stop there.  I have checked the purple wire going to the center wiper and I can vary it from 0-5volts.  I can also hear the 12 mhz on my other radio. However it will not go on to display the frequency on the display.  So I'm wondering does the "Raduino v1.01" really tell me that the software is working correctly in the nano board? I don't really have much experience with this stuff, just downloaded the IDE  and got a few books on the arduino, I'm on  the path to learning about them.  My bitx40 does not have  L4 and C93 on it,  So does the uno and board that attached to it provide all the signals that the bitx40 needs?  I watched Ashhar Farhan's video on troubleshooting and I did not have a signal at Collector at Q7 the 5 mhz on the main board.  Is this normal if the L4 and C93 are not mounted on the main board?  I feel that I need to get the display working before I go on with this.

Thanks for all input
Tom WD9GON

Re: Why I bought a uBITX

Ashhar Farhan
 

While a soldering iron and a screw driver is all you need to setup the ubitx, i would encourage everyone to experiment with testing and measuring.
A resistive swr bridge is just three resistors and a transformer. An RF voltmeter is a diode and a capacitor. An HF oscillator is a one evening project. Raduino, with a different firmware can be a programmable signal gemerator and a voltmeter too. Each of these kind of projects will enhance your understanding and bring immense joy to your hobby.  
- f

On Fri, 18 May 2018, 00:46 Jerry Gaffke via Groups.Io, <jgaffke=yahoo.com@groups.io> wrote:
I haven't seen a lot of flames here regarding imprecise measurements.
If you have the Harbor Freight digital voltmeter (often free with any purchase), you are about as well armed
as most folks here in the forum.  If you have trouble troubleshooting, somebody may urge you to build a diode RF probe,
that's about it.

Some do have good lab gear and and decades of experience, can measure filter passbands or
intermodulation distortion or harmonic content, and they then report back telling us what they saw. 
But that sort of thing is definitely not required.
If anybody suggests you should spend more on test gear than you did on the radio,
that's your opportunity to go ahead and flame them good.

Jerry, KE7ER

On Thu, May 17, 2018 at 10:07 am, kq2q2000 wrote:
I’ve been Flamed in the past for not being Precise and well Documented. Opinionated Flamers are ready and armed 24/7
It is easier to remain Silent, Learn and Elmer the appreciative Experimenters Locally. 

Re: ND6T AGC implementation for uBIT-X

Kees T
 

The AGC and Pop Fix boards have both been redone and are already at the board house. Copies of the new ones are in the "Files" section.....as before.  Some of the changes were very slight but it will make for a better board and more reliable fix .....provided that nothing else got hosed. 

That wattmeter board may work quite well at lower power levels just as long as you have a 30dB span (1mW to 1W, 5mW to 5W, etc) . Testing yet to be done.

73 Kees K5BCQ

Re: Using IRF530 outputs and 2N3553 drivers in ubitx

Rahul Srivastava
 

I have often thought of using the IRF's in common gate mode to avoid gate capacitance issues. Never came across such a design, gain would be slightly low but should have better stability and better high freq performance after all it was done all the time with tubes.

Rahul VU3WJM

Re: Raduino not working 0 Volts on Pin 6 (red wire) #ubitx-help #ubitx

Gary Anderson
 

Rogier has a few threads open on his problems.  Casually, hard to keep up with where he is at the moment.
He has shared more information than is contained in this thread.
I usually _try_ to look a threads I've responded to, to see if progress is made or if additional inputs  / coaching might be helpful.
I can see how using non threaded email, one might not understand this perspective.
So, please if you have an issue where others are trying help. Please stay on the same thread e.g. subject line.  Easier for others taking their time to try an help.

Re: share your BITX success stories

ajparent1/KB1GMX
 

Well took it out of the box and wired up the connectors and all and having on the bench spread out.
haven't measured power in any exacting way for at 11V I see 6W at 7mhz.  Receives well.

I then installed my mod for the audio amp to run it at 8V regulated.  It works.  Only one part
used an lm7808.

Changed the resistor on the back of the LCD from 100ohms to 330 to damp down the brightness a bit.
Adjusted pot on the back of Raduino for better contrast.
Flipped the 5V regulator around so it doesn't hang off, my case needed that bit of space for a really
good encoder.

Next step is the bias on Q70 its sitting at 1.6V way too low for good overload results. 16k resistor will fix that.

After that replace q90 with 2n2222A and then check the bias it seems to be at higher current than needed.

At this point I'll break for an order of a dozen MPSH10 and some other RF parts to try.

The case, no matter what they say the drillin and blastin is the work:
While waiting I'm working the fitment of the case and the various parts.   Other things that
will need to be on the panel is the power led, some form of metering for received signal
strength and relative TX power (bargraph but not on LCD). 
Mic jack, headphone, and antenna jack are  on the front panel along with LCD and power
switch.  Then we have audio level and rf-gain.  All this goes in an area 8.x inches by 2.25 inches.
It has the potential for being cramped if I use the larger tuning encoder.   The display
eats panel space too.

plodding on..

Allison

Re: share your BITX success stories

Doug W
 

On Wed, May 16, 2018 at 09:48 am, Doug W wrote:
I just missed the illustrious 1000mi/w
I guess this is a wishing well because I just hit 1,128.9mi/w with a QSO from Brazil.
Just in case this thing works....oh mighty list I still haven't won the lottery.
 
--
www.bitxmap.com

Re: rough draft of how to connect BITX to PC for digital modes wiki

Doug W
 

I had the wrong link for the FTDI cable.  It should be https://www.ebay.com/itm/201486735007  Also worth noting, you could probably save on shipping to order your parts from less suppliers than I did.  This wasn't the top of my project list so I just kept adding parts on to orders for other things as I thought of it.
--
www.bitxmap.com

Re: Asking for help solving a Hendricks kit BitX20 PA oscillation problem

ab2ts
 

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.

Re: Mic doesn't work in bitx40 #bitx40

qonita.salimah@...
 

Thank you for your reply..
So the one that I bought is the electret condenser mic. 
When I didn't connect the mic to the circuit the voltage from 4.7KOhm resistor is about 9.5-10Volt. But when I connect it to the mic, the voltage suddenly drop to the 0.131-0.135Volt. 

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: share your BITX success stories

John
 

I've been working FT8 for a few days on my shiny new uBITX tied to a homebrew G5RV set up as an inverted v.  Just finished a 20m QSO with Tasmania.... thats over 9000 miles on just less than 9w! Amazing little rig!

73's de W5JXN