Date   
Re: power supply

Ian Reeve
 

The ubitx  or bits does not need more than 2 amps but crucially no more than 12v for the supply voltage.The supply you have can be used as long as it can be reduced to 12 v or slightly less, 13.8 volts is too much.I use a 12 v battery or a 19 or 20 volt computer laptop supply which tend to be well regulated and noise free.A suitable voltage regulator than be bought easily to reduce down to 12v.If you can find a 12v laptop supply you have a neat reliable solution.



From: BITX20@groups.io <BITX20@groups.io> on behalf of Doug W <dougwilner@...>
Sent: Monday, August 19, 2019 2:28:17 PM
To: BITX20@groups.io <BITX20@groups.io>
Subject: Re: [BITX20] power supply
 
why not just use your shack power supply with a fuse?

Re: power supply

Evan Hand
 

dgclifford,

I would look into a buck boost supply that can supply 3 amps.  This would work with both power supply options.  The potential disadvantage is the possible HF interference from the switching nature of the device(s).  I had read here that some included an LC filter after the supply to overcome this disadvantage.

The buck boost would allow a constant 12 vdc to the rig.  Though the finals are not that fussy (could run the 19.5 vdc direct from the laptop supply) the main board is.  It really should stay around 12 volts unless you start adding heat dissipation to the Raduino regulator.  I found that higher than 12.5 volts the regulator got very hot.  I am supplying 13.5 volts, I added a heat sink to the regulator, AND dropped the voltage to the main board  through 2 1n4001 diodes.  The diodes are not in the circuit to the finals.  

If you run higher voltage to the finals, you will need to beef up the heat dissipation.  Most have just added a fan to run when transmitting to conserve power.  Not needed if you feed the rig with 12 vdc as designed.  You could wire the circuit to run the fans when on the laptop supply and not when running from battery to conserve power.

There are quite a few buck boost supplies on the web.  A lot of bear bones with adjustable voltage are available for under $2 each in small quantities (2-8).  The devices with built in displays run more.

The above are my recommendations, and may be in error.  I would verify and test.

73
Evan
AC9TU

Re: Help #arduino

Jack Purdum
 

I've written to Paul privately several times, and I think I got a response once. However, he does seem to be very responsive to questions posed on his Forum. Try posing your question here:




Jack, W8TEE


On Monday, August 19, 2019, 9:39:16 AM EDT, Ashhar Farhan <farhanbox@...> wrote:


It is a pity that the teensy forums are blocked from indian ip addresses. Paul is quite unresponsive on emails too. I had written a few times to him for help with in getting teensy into one of our space missions. I needed to know if the components used were space worthy. I was really keen.No replies ensued. 
After that, we just went ahead and scratch built an ATMEGA328P based system.


On Mon 19 Aug, 2019, 6:56 PM Jack Purdum via Groups.Io, <jjpurdum=yahoo.com@groups.io> wrote:
On Monday, August 19, 2019, 9:12:39 AM EDT, Raj vu2zap <rajendrakumargg@...> wrote:


So far I don't think anyone has written code for that display.

You can use lots of  different displays but you will have write your code/sketch.

Raj

At 19-08-19, you wrote:
>I am han radio from cuba. I build the Ubitx and working fine. The questions is
>I can use GLCD 32160 to put un my Ubitx




Re: Help #arduino

Ashhar Farhan
 

It is a pity that the teensy forums are blocked from indian ip addresses. Paul is quite unresponsive on emails too. I had written a few times to him for help with in getting teensy into one of our space missions. I needed to know if the components used were space worthy. I was really keen.No replies ensued. 
After that, we just went ahead and scratch built an ATMEGA328P based system.


On Mon 19 Aug, 2019, 6:56 PM Jack Purdum via Groups.Io, <jjpurdum=yahoo.com@groups.io> wrote:
On Monday, August 19, 2019, 9:12:39 AM EDT, Raj vu2zap <rajendrakumargg@...> wrote:


So far I don't think anyone has written code for that display.

You can use lots of  different displays but you will have write your code/sketch.

Raj

At 19-08-19, you wrote:
>I am han radio from cuba. I build the Ubitx and working fine. The questions is
>I can use GLCD 32160 to put un my Ubitx




Re: power supply

Doug W
 

why not just use your shack power supply with a fuse?
--
www.bitxmap.com

Re: Help #arduino

Jack Purdum
 

On Monday, August 19, 2019, 9:12:39 AM EDT, Raj vu2zap <rajendrakumargg@...> wrote:


So far I don't think anyone has written code for that display.

You can use lots of  different displays but you will have write your code/sketch.

Raj

At 19-08-19, you wrote:
>I am han radio from cuba. I build the Ubitx and working fine. The questions is
>I can use GLCD 32160 to put un my Ubitx




Re: Help #arduino

 

So far I don't think anyone has written code for that display.

You can use lots of different displays but you will have write your code/sketch.

Raj

At 19-08-19, you wrote:
I am han radio from cuba. I build the Ubitx and working fine. The questions is
I can use GLCD 32160 to put un my Ubitx

power supply

dgclifford@...
 

hello i am preparing for the arrival of my ubitx  and whilst i have a 35 amp power supply for my shack i think it would be best to have a lower rated supply for the bitx. i have a few ex laptop supplies, should i modify one of these  . if  use the bitx away from the shack i plan to use 11.1 v lipo batteries, but i  need something slightly less powerful  for shack. use any ideas would be great    dave c  gw0nvf.

Re: Help #arduino

Jack Purdum
 

Hi Evan:

As many of you probably already know, PJRS, the makers of the Teensy family, just added the Teensy 4.0 and it is a beast! Some features include:

– ARM Cortex-M7 at 600 MHz
1024K RAM (512K is tightly coupled)
2048K Flash (64K reserved for recovery & EEPROM emulation)
– 2 USB ports, both 480 MBit/sec
– 3 CAN Bus (1 with CAN FD)
– 2 I2S Digital Audio
– 1 S/PDIF Digital Audio
– 1 SDIO (4 bit) native SD
– 3 SPI, all with 16 word FIFO
– 3 I2C, all with 4 byte FIFO
– 7 Serial, all with 4 byte FIFO
– 32 general purpose DMA channels
– 31 PWM pins
– 40 digital pins, all interrrupt capable
– 14 analog pins, 2 ADCs on chip
–  RTC

plus more. Paul was very careful when he selected his Beta testers for it, and most were frequent contributors to his Forum and the authors of major libraries. They been beating on it for almost a year, so I think the core should be pretty stable. The footprint is actually smaller than the 3.6 and the cost is, too...$19.95. It's overkill for many projects, but the depth of that resource pool opens a whole new world in many arenas!

Jack, W8TEE

On Sunday, August 18, 2019, 11:20:55 PM EDT, Evan Hand <elhandjr@...> wrote:


The short answer is yes, if you add the screen features you want to the Arduino firmware.  I am not aware of any such firmware available.  There is also a shortage of I/O in the stock Raduino. 

I would suggest that you first look at the Nextion display work that can be found here: http://www.hamskey.com/. 

Dr. Lee has written software and screen designs to work with the Nano that came with the uBitx.  With all the added features, there is very little room for more modifications in the Nano code.  You do need to purchase a Nextion display with touch screen capability. https://nextion.tech/  Be sure to verify the screen size and the enhanced version with touch capabilities to work with the KD8CEC software.  I used both the 2.4 and 3.2 inch enhanced versions.  Available from multiple vendors.

There is the also JackAl add on board that did change the processor to one with more memory and speed.  That is available here: https://qrpguys.com/jackal-for-%CE%BCbitx  This has higher capabilities, at a higher price.  Be sure to note that the listed price for the board does not include every thing that you need to make it work.

You can go the route of converting the Nano code to a larger/more powerful processor like the Teensy on the JackAL board or other newer Arduino based system.  Regardless, that will be a significant effort.  Would be curious to see any results that you come up with.

73
Evan
AC9TU

Re: bitx20 problems #bitx20help

 

Hi Dries,

It looks like you have been working hard on this.  Good job to get this far!  It is much harder to work from scratch, than to build a kit, but you can learn a lot!

This site:  http://golddredgervideo.com/kc0wox/  is probably your best resource.  OM KC0WOX does a great job of explaining a lot about the kit and shows many measurements done with a homemade RF probe and also has a lot of videos of the various signals on an oscilloscope.  I hope this can help you diagnose your trouble.

You used six 2n2018 for your HF amp, I assume you are using Farhan's schematic for that?

What diode are you asking about for the 1n4001.

I'm not sure that the ne602 has enough power to drive the final amp all by itself.

FT37-43 is just what you want for all the broadband transformers used in the radio.  Do not use them for the final low pass filter -- you need powdered iron cores for that.

Your VFO and BFO signals should look clean like in the linked site's videos.  Be sure to have your scope probe on the proper test point, and use a 10:1 probe if possible.

From your video, sometimes it seems like your scope has a problem as the signal is not blanking on the trace return?  This can make good signals look bad.

Be sure when you are posting questions here, that you specificy where your test points are for your measurements.  This can help us understand your questions and measurements better.

73,


Mark -- N7EKU/VE3

Re: Help #arduino

Evan Hand
 

The short answer is yes, if you add the screen features you want to the Arduino firmware.  I am not aware of any such firmware available.  There is also a shortage of I/O in the stock Raduino. 

I would suggest that you first look at the Nextion display work that can be found here: http://www.hamskey.com/. 

Dr. Lee has written software and screen designs to work with the Nano that came with the uBitx.  With all the added features, there is very little room for more modifications in the Nano code.  You do need to purchase a Nextion display with touch screen capability. https://nextion.tech/  Be sure to verify the screen size and the enhanced version with touch capabilities to work with the KD8CEC software.  I used both the 2.4 and 3.2 inch enhanced versions.  Available from multiple vendors.

There is the also JackAl add on board that did change the processor to one with more memory and speed.  That is available here: https://qrpguys.com/jackal-for-%CE%BCbitx  This has higher capabilities, at a higher price.  Be sure to note that the listed price for the board does not include every thing that you need to make it work.

You can go the route of converting the Nano code to a larger/more powerful processor like the Teensy on the JackAL board or other newer Arduino based system.  Regardless, that will be a significant effort.  Would be curious to see any results that you come up with.

73
Evan
AC9TU

Re: bitx20 problems

Jerry Gaffke
 

Dries,

Here's what I hope is a helpful answer to your questions about the Bitx20

Yes, you could use FT-37-43 cores on the transformers.
Just duplicate the transformers used on the Bitx40, 10 turns trifilar:
    http://www.hfsignals.com/index.php/2017/11/23/bitx40-circuit-description/

Carrier suppression on transmit mostly depends on T3 and the two nearby diodes
being wired correctly, also the nearby 100 ohm pot must be adjusted for best suppression.
The crystal filter will then improve on this somewhat, assuming the BFO is adjusted correctly.

Curt's suggestion to check the BFO placement is a good one.
Have you tried adjusting the 22pF trimmer in parallel with L3?
There's a whole paragraph about tuning in the BFO on   
    http://www.phonestack.com/farhan/bitx.html
starting with the words "On amateur bands above ..."

Here's a technique for debugging a receiver that might prove useful:
  http://bitxhacks.blogspot.com/2016/12/troubleshooting-bitx40.html
Farhan uses a short piece of wire as an antenna, perhaps 1 meter long.
It picks up houshold QRM, and he injects that into various parts of the radio,
listening to the result out of the speaker.  Perhaps this will help.

Once the receiver mostly works, you might verify the crystal filter shape.
To do this, measure the audio coming out to the speaker using a scope
while tuning through a strong carrier in one of the bands.  
Ideally, you would start hearing it around 300 hz on one side of the carrier, 
it shouldould quickly rise up to full volume and stay there till around 2500 hz,
at which point the volume should rapidly fall into oblivion again.

I am not quite sure what to say about all of the "mixing frequency products"
that you hear in the receiver.  I don't know how clean this radio was,
but they should not get in the way of casually tuning in stations across the band.
It could be just a matter of a wiring error or bad part.
Or it could depend on how the parts were placed on the board.

When building the crystal filter, it is best to choose a set of 
four 10mhz crystals that match in frequency within perhaps 100hz
when plugged into an oscillator, using a frequency counter.   
It may be necessary to do this if the above test of the filter shape looks wrong.

We can worry about Q14 and the 2n2218 JBOT power amp
after you get the receiver working properly.
 
If you get stuck, you can certainly ask questions here.
But best would be to find a local club of radio amateurs who know
about working on radios and have appropriate test equipment.
Perhaps someone there would like to help.

Best Regards,
Jerry Gaffke, KE7ER


On Sun, Aug 18, 2019 at 05:29 PM, Curt wrote:
hard to quickly resolve how many issues remain with your build.  on receive - I wonder if BFO is properly adjusted.  note this oscillator must be appropriately adjusted to mix the RF into the crystal filter to provide the correct audio. 

most everyone here is okay with buying a bitx or ubitx board from India, and wiring it up.  there are still modifications to consider.  if you must build a rig - I suggest visiting QRP-LABS.com. 

Re: Reduced power on 40 meters. #ubitx #v5

ajparent1/KB1GMX
 

Brad,

In the past every time that issue has been seen it was the 40 low pass filter having
wrong components installed at assembly.  Other wise the issue would be evident
on other bands.

Generally the power goes down as one goes up from 80 through to 10M.
Nominally 40m should be less than 80 and more than 20.  This is assignable
to the power amp. 

If 40 is much lower than 20 then low pass filter or switching is broken.

Allison

Re: bitx20 problems #bitx20help

Ashhar Farhan
 

Dries,
I remember you mentioning that you had changed things around. The one you posted is exactly the original. Can you post your own version' diagram?
Second, what kind of equipment do you have to troubleshoot? Do you have access to an oscilloscope or an rf power meter?

- f


On Mon 19 Aug, 2019, 1:40 AM dries breughe, <driesbreughe@...> wrote:
the circuit is from the transceiver has already been posted and is on your own website.

here the circuit of the hf amplifier

Re: bitx20 problems

Curt
 

OM

hard to quickly resolve how many issues remain with your build.  on receive - I wonder if BFO is properly adjusted.  note this oscillator must be appropriately adjusted to mix the RF into the crystal filter to provide the correct audio. 

most everyone here is okay with buying a bitx or ubitx board from India, and wiring it up.  there are still modifications to consider.  if you must build a rig - I suggest visiting QRP-LABS.com. 

my ubitx is receiving as I type - and I confess to having a Yaesu but it has been off several days.

73 Curt

Re: Help #arduino

Curt
 

Senior OM

fine news on your successful build.  I think you refer to a larger LCD display?  there are 2 custom versions of uBITX software but I think they only work with color displays - others can correct me if I am wrong.  even if that display can connect to ubitx, the firmware will not likely support it. 

I use the simple 2 line LCD and it works nice enough. 

enjoy your ubitx and I hope to QSO

Curt WB8YYY

Help #arduino

co8pap@...
 

I am han radio from cuba. I build the Ubitx and working fine. The questions is 
I can use GLCD 32160 to put un my Ubitx

Re: bitx20 problems

Dexter N Muir
 

Ham since '07, building a Bitx20 in '12? OK, have you built simpler in between? That should have taught you the basics of troubleshooting and given you some basic test-gear.
A Bitx2o from scratch is NOT a beginner's project!
I'd recommend a careful perusal of SolderSmoke blog: Bill N2CQR in particular is a consummate builder, returning to the simple and re-starting just for the joy of it - and Pete N2CQW doing real advanced stuff, again for the joy of it. IIRC Bill built bitxes before Farhan's kits - merely as proof-of-concept.

73
Dex ZL2DEX

Re: VOX Issues to be aware of. Or, suspected new digital mode.

Tom, wb6b
 

On Sun, Aug 18, 2019 at 05:33 AM, bobolink wrote:
ripped from CODEC2
CODEC2 looks interesting. It seems to be a breath new life for older research and makes it work well thanks to modern DSP technology. The original researchers could not get past a certain technology point.

Well unless you have a government sized budget. 
https://commons.wikimedia.org/wiki/File:SIGSALY.jpg

If you think learning Morse Code is hard, imagine learning this keyboard. Maybe someone should come up with a Vocoder Code Tutor. Must have the lowest bit rate for any digital voice mode.
https://encyclotronic.com/synthesizers/misc-instruments/vocoder-r1258/

Probably could send voice at WSPR bit rates. Imagine that, voice WSPRing.

Looks like FreeDV (based on CODEC2) can be implemented with one of the more powerful STM32 processors, maybe one of the newer Teensy boards. Might be fun to add digital voice to the uBitx.
https://freedv.org

Well, if the snoring VOX issue cannot be solved, maybe just some kind of auto ID every 10 minutes to keep his transmissions legal.

Tom, wb6b

 

Re: bitx20 problems #bitx20help

dries breughe
 

the circuit is from the transceiver has already been posted and is on your own website.

here the circuit of the hf amplifier