Date   
Re: Calibration #calibration

d.maccallum@...
 

Well this is a work in progress. Every thing keeps getting improved and a lot of the guys doing the improvements assume everyone knows the history of how thing evolved. So whats happening here is all all the information a newbie needs is not tied together in one place. So here is what I found out so far to get my mbitx V5.1 running right after I got everything running and the wiring checked ok using the factory firmware.
 Here is what information and files that I found helped me get my rig running right  for thr mbitx V5.1 as of 9-22-2019.:
1. down loaded uBITX_CEC_V1.200_16P.hex  file in folder. I found a programming USB to MINI cable at my local drug store today. Download the hex file using XLoader software. A software driver needs to be installed in your computer to talk to the Nano in the mbitx radio.
2. Read the KD8CEC uBitx manual for V1.072 by Rod KM6SN manual ua1072_087 at web site: ubiix.net/manual-kd8cec-firmware/ Learn how to use the three types of button presses on the indexer knob push button. I wondered why the separate button was required in paralleled with the existing indexer push button....and now I know the rest of the story. A lot of whats in this manual works for the V1.2.
3. Go to this web site and read all the links:  http://www.tobeca.fr/f4ija/doku.php?id=ubitx:calibration

CUL on the Bands 73

Dave N8KZ

Re: Calibration #calibration

riz-qcx@...
 

Wow, that's great!  Very much appreciated by those of us who are trying to learn several things at the same time - this really clarifies it.

Thank you!

+jeff AJ6IY

Re: uBITX full design

Jerry Gaffke
 

I agree with Curt.
A good student project would be to get the uBitx, and then try to improve it somehow.
Lots of fodder in this forum if looking for ideas of what to do.

Jerry


On Sun, Sep 22, 2019 at 03:27 PM, Curt wrote:
Jerry gave a nice description of the board.  An EE named Allison has separately commented on optimizing the PA portion - and she went out and designed a better PA layout assisting Hans Summers at QRP-Labs (they currently offer this PA kit over there).  Years ago a prof somewhere got his students to build a QRP rig, Norcal 40A maybe.  I see you already built a McHF so I don't see a lot of upside to you building your own ubitx from scratch.  likely you have already dug into the nifty synthesizer components that are a key piece of modern QRP likes ubitx and QCX. 

Re: uBITX full design

Curt
 

Jonathan

now after reading your QRZ listing I see you are a student, not working on a faculty project idea, but a personal project for your program there. 

as Jerry mentioned, the full component BOM is available.  even if they shipped you a board, still not a worthy student project to assemble a ubitx.  there are some things that could be expanded, like adding VHF capability (the existing 45 MHz may not be so good).  I have a paper where KK7B (a prof) has related HF layout to microwave MMIC chip design.  so some analogous learning is indeed possible. 

Jerry gave a nice description of the board.  An EE named Allison has separately commented on optimizing the PA portion - and she went out and designed a better PA layout assisting Hans Summers at QRP-Labs (they currently offer this PA kit over there).  Years ago a prof somewhere got his students to build a QRP rig, Norcal 40A maybe.  I see you already built a McHF so I don't see a lot of upside to you building your own ubitx from scratch.  likely you have already dug into the nifty synthesizer components that are a key piece of modern QRP likes ubitx and QCX. 

best wishes in your study and remaining time at that nice (rather Hokie) venue.

Curt

Re: uBITX full design

Jerry Gaffke
 

Jonathan,

A search on the web and on ebay for "ssb transceiver kit" gives a few kits
that require more assembly than a uBitx, but none that I am familiar with.
Perhaps the Klopik out of Russia, if wanting a challenge?
    https://www.eham.net/ehamforum/smf/index.php?topic=106044.0
    https://forums.qrz.com/index.php?threads/russian-klopik-2-transceiver-kit.500188/

Some of the ebay kits come with no power amp, no low pass filters, no vfo, ...
And some just plain don't work.

Farhan encourages others to produce his designs and sell them.
There have been several Bitx20 kits, and even multiband versions of it.
But I'm not seeing any just now, the uBitx is very competitive.

QRP-Labs has the successful QCX transceiver, but it is single band, and for CW, not SSB.
QRP-Labs is planning to someday release the very promising QSX all-HF SSB transceiver, 
that might be worth waiting for.    https://www.qrp-labs.com/qsx.html

If what you really want is a uBitx where you install all the surface mount parts yourself
on a known-to-work PCB, your best bet might be to buy one from hfsignals
and take a heatgun to it.

Jerry, KE7ER



On Sun, Sep 22, 2019 at 12:32 PM, Jerry Gaffke wrote:
Perhaps just build "ugly style" or "Manhatten style" on copper clad circuit board,

Re: Calibration #calibration

Adrien F4IJA
 

Please check here http://www.tobeca.fr/f4ija/doku.php?id=ubitx:calibration


For now it's just about frequency calibration but it's a work in progress for a method for bfo in some days or weeks. 
-
73's
Adrien F4IJA
https://www.qrz.com/db/F4IJA

Re: Collection of knowledge about CEC firmware? #firmware

riz-qcx@...
 

Thanks to all who responded - I hope I didn't come off as complaining.  This is a fantastic little radio (which I'm looking forward to tinkering with, as microcontroller stuff is right up my alley!), and the amount of stuff which folks have gotten it to do is nothing short of mindblowing!  I feel like I should have bought two, though, as I'm much bolder about my experimentation when a  mistake isn't likely to shut me down for a few weeks.  :) :) :)  This hobby is mostly about tinkering for me;  I don't own any other HF radios capable of transmitting (well, except this 20-meter QCX kit which I'm still in the process of troubleshooting...) so until I get this unit up and running I'm going to be off the air.  

I just wanted to make sure I wasn't missing something; I've definitely had the experience in the electronics world of struggling over weeks and months to learn something only to discover I'd been Googling wrong.  :) :) :)

Re: uBITX full design

Curt
 

Jonathan

Contact Farhan direct to explore what's possible. it might be possible to get boards assembled without toroids and the larger parts installed. I imagine the board is the primary IP to preserve the work for folk in India. Perhaps the effort can expose the students also to manufacturing by some video perhaps. I am confident Farhan will share some fine details with the students on PA circuitry, filters and isolation. Great to see your interest.

Curt wb8yyy rf engineer

Re: uBITX full design

Jerry Gaffke
 

Jonathan,

Be aware it might not be as trivial as it looks.

The transformers are described here:
    http://www.hfsignals.com/index.php/ubitx-circuit-description/
Search for "Coil Details".

The KiCad files are not available, that was some sort of requirement
when they set up HFSignals to build this stuff.
Perhaps to get a business loan they had to keep some part of the design private.
The remainder of the design is open source, and building from scratch is encouraged.
The uBitx is a two layer board, the bottom side is mostly ground plane.
Perhaps just build "ugly style" or "Manhatten style" on copper clad circuit board,
that way you have a solid ground plane under the entire design, which is highly recommended.

All quartz crystals in that IF filter should be matched by hand to within 100hz or so,
that means building a crystal oscillator and having some way to accurately measure frequency..
If your quartz crystals have different characteristics than what hfsignals uses,
you will need some way to determine the passband of the IF filter and adjust the filter shape
as described in Experimental Methods in RF Design (and/or search for Dishal on the web).

You will need some way to sniff and measure RF, an Antuino would be ideal,
though you might get by with a diode RF probe and a Harbor Freight DVM.
A good scope would be nice, perhaps 50mhz or more of bandwidth.
The nanoVNA would be worth looking into, shows complex of 1 and 2 port networks,
and thus is an education in itself.

If you are serious about studying "RF and Microwave", all of the above is worth the investment.

And lastly, maybe get a working uBitx from hfsignals, so you can
know for sure what the signals levels really should be when yours does not work.

Many have built radios like the uBitx from scratch.
But few find it easy.

Jerry, KE7ER


Re: Collection of knowledge about CEC firmware? #firmware

Ashhar Farhan
 

You have the K8CEC website itself anf the github repo with sufficient documentation. Additonally, ubitx.net offers a more narrational form of documentation.

F


On Sun 22 Sep, 2019, 8:53 PM Ted via Groups.Io, <k3rta=yahoo.com@groups.io> wrote:
Yes, direct langage toward setting parameters for WSPR mode in TX would be fantasmic.  I'm home on surgical recovery and will be restricted to brain exercise only ( as opposed to tower reconstruction)  and so now's a good time to play with it.


-ted

uBITX full design

Jonathan Kayne, KM4CFT
 

Hi,
I am trying to see if I can do a full assembly of the uBITX, that is, I want to start with a BARE PCB and hand solder on the SMD components. 
I was wondering if the KiCAD files were available or perhaps a BOM so I know what type of transformers are being used.
I am planning on using it in a school project, so that's why I am asking.
I am more than happy to reverse engineer the PCBs if need be.
Also, I was wondering if there was anything particular I would need to know about the trace layout for the boards. Is there a ground plane on the bottom layer with the other traces on the top? (I couldn't find pics of the bottom side so I wasn't sure)
Any help would be much appreciated!
73,
-Jonathan Kayne, KM4CFT
Virginia Tech Electrical Engineering (RF and Microwave Concentration)
Virginia Tech ARA Vice President

Re: Collection of knowledge about CEC firmware? #firmware

Don - KM4UDX
 

Jeff -- the doc is "distributed".  Meaning it is a wild wild West situation. Google search seems the only (poor) tool to identify CEC-related  doc, vids, discussions. But others know better and someone is always able to say...oh that file is here in location XYZ, obviously. 

I took the MM displayed values as exactly reflecting current config parameters.  While simple, having a semi-gui interface to uBITX parameters is heavenly. To be able to read,c  write, reboot, observe/play, then repeat as necessary, was a revelation.

On WSPR, you might want to read up on the WSJTX doc describing the WSJTX freq calibration procedures.  These process within wsjtx are the most wicked clever bits of code/processes i've ever encountered. Yes, I don't get out much. Hahah.  The CEC software essentially implements a short hand version of the same process in WSJTX. So, if you understand how WSJTX does it, you will be most likely be able to figure out how CEC does it. 

Don
Km4udx

Re: Collection of knowledge about CEC firmware? #firmware

Ted
 

Yes, direct langage toward setting parameters for WSPR mode in TX would be fantasmic.  I'm home on surgical recovery and will be restricted to brain exercise only ( as opposed to tower reconstruction)  and so now's a good time to play with it.


-ted

Re: WTB 680nF Inductors #parts

 

Hi,

Not to complicate matters, but in old posts I've seen two different inductors being discussed:  680nH ones on a filter, and 680uH ones placed on the relays.  Has anyone tested either of those strategies to show measured reductions in the problem spurs on SSB in the higher frequency bands?  I also recall others saying that the 680nH filter inductors were causing fairly significant power reduction on 40m -- was this always the case or has the modification worked for some and not for others (depending on what)?

73,


Mark.

Re: WTB 680nF Inductors #parts

Dale Hardin
 

Raj, l don't want to have to buy 100 off eBay, so that's why I am looking to find the parts on the group.  Regards, Dale



On Sun, Sep 22, 2019, 2:08 AM Raj vu2zap <rajendrakumargg@...> wrote:
I've tried similar ones and they DONT work. The issue with the original toroids is that
their leads seem to pick up TX signal and cause a mess.

Change the relays and you are almost there. Use SHIELDED smd insuctors and you
will get reduction in spurs. Any old inductor there wont do.

If the 680nh does not help then you have the wrong type.

Raj

At 21-09-19, you wrote:
I bought these, and reasonably-shipped:

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F352066947527


Ted
k3rta


--
Dale Hardin, KS4NS
Elberta, AL

Re: WTB 680nF Inductors #parts

 

I've tried similar ones and they DONT work. The issue with the original toroids is that
their leads seem to pick up TX signal and cause a mess.

Change the relays and you are almost there. Use SHIELDED smd insuctors and you
will get reduction in spurs. Any old inductor there wont do.

If the 680nh does not help then you have the wrong type.

Raj


At 21-09-19, you wrote:
I bought these, and reasonably-shipped:

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F352066947527


Ted
k3rta

Re: Contrary Raduino

Ashhar Farhan
 

It looks like your potentiometer doesnt have a +5v connected. Can you confirm that the pot's center pin changes voltage smoothly between 0 to 5v as you tune it?
- f

On Sat 21 Sep, 2019, 10:07 PM JD Hill, <w9jdh.qrp@...> wrote:
Hello to the group. This is my first post here.
I am building A BITX40 and I am having a lot of trouble with it and I am about to believe it is a bad Raduino.
Regardless whether I hook it up via the USB port or by connection to a 12 volt supply. The display comes on but the only thing that is displayed is: VFO A: 6.9980 Mhz.

It draws about 135 mA but the function switch and the 10 turn tuning pot do not work.
This is my first experience with a microprocessor in my 43 years of being licensed. I have spent many hours building and trouble shooting,  but this has me lost.

TIA
Jimmy,. W9JDH


Re: Calibration #calibration

d.maccallum@...
 

Adrien, thank you for this excellent information. I will be downloading V 1.2 or higher firmware and use your method for calibration. Should have my programming cable for the nano by end of next week.

TNX FER THE HELP 73

Dave, N8KZ

Collection of knowledge about CEC firmware? #firmware

riz-qcx@...
 

I have a v5 µBITX that I've been fiddling around with for a while, and it looks like just about all the stuff I'm interested in being able to do with it will be better-enabled with the CEC firmware.  So, I got v1.200 and built it (I still have the stock parallel display) because I could not for the life of me make any of the hex loaders work - but was able to build and load it using the Arduino IDE.

So far, so good.  There are a number of issues with it that I expect will all get worked out eventually (for example, the CW filters make a CW signal barely audible - I've seen allusions to that issue on this board, and to there being settings which help, but I have been unable to find those settings.

I also just grabbed the uBITX manager software, v1.110 - I was disappointed to find out it was a Windows program, but managed to dig up an old laptop.  First thing I did was read the settings and save them - but some of this stuff looks Wrong.  (Example - "LSB calibration" is 0, but "USB calibration" is 11057115.  Not sure what these are...  Also, Si5351 I2C address is set to 0xff, while there's a warning in red which says "Warning: default value:0 or 0x60".  Worrisome!

Anyway, this brings me around to:  is there a repository for knowledge about this firmware and what all the settings are?  I found a "User Manual" for version 1.072, which helped, but the pieces I am particularly interested in are either not implemented yet, or just not written about.  (Example: how is the WSPR stuff set up and used?  I would love to know!)   I've looked around hamskey.com and ubitx.net, but it's all pretty fragmented.  Failing that, can anyone point me to threads here which would help?

I suppose if I need to, I can look through the source code, but I bet other folks have gone through all this before.  :)  Did I also forget to mention that I don't have a lot of direct experience with HF rigs yet?  :) :) :) It's also complicated by the fact that I live smack in the middle of San Francisco with all the noise that entails, so even with the antenna I've got set up (20m EFHW) I can't hear a lot


Thanks in advance,

+jeff AJ6IY

Re: Calibration #calibration

d.maccallum@...
 

Thank you for saving this old dog from barking up the wrong tree. I will down load V 1.2, Big help thanks again...

I have a dummy load and a good comm receiver to check the ubitx tx with. The TX and RX are working but the BFO adjustment for clear audio is very bad. cw works very nice and clear!

OK big help CUL 73

Dave N8KZ