Date   

Re: Firmware loading ignorance

Bill Robbins
 

Also should simply load factory defaults and start over?

On 11/24/2020 2:18 PM, Evan Hand wrote:
Bill,
I should also point out that the zip archive has a text file that describes the display hardware that each of the .hex files uses.
FileNameInfo.txt

73
Evan
AC9TU


Re: Firmware loading ignorance

Bill Robbins
 

Evan:

While I have you here answer this for me. My v5 has audio but deaf for signals.  In looking at memory manager settings I see my default for USB Calibration at 11995000.  Others are at 11054600.  Is that why mine bitx is deaf?

Bill

On 11/24/2020 2:18 PM, Evan Hand wrote:
Bill,
I should also point out that the zip archive has a text file that describes the display hardware that each of the .hex files uses.
FileNameInfo.txt

73
Evan
AC9TU


Re: Firmware loading ignorance

Bill Cromwell
 

Hi Bill,

You already have the help you wanted getting new software installed. For what it's worth, updating the software does not change any of your alignment of BFO settings. You only need to do a realignment if you change the microcontroller IC on your Raduino board. Or maybe change the clock crystal.

73,

Bill KU8H

bark less - wag more

On 11/24/20 1:18 PM, Bill Robbins wrote:
I now have my ubitx20 v5 assembled.  I was working fine and I had begun the alignment process.  Then it occurred to me to load the KD8CEC firmware rather than going thru alignment twice.
I have loaded sketches previously but it has been sometime.  I followed the KD8CEC instructions (I thought).  But I get no satisfaction.
So I tried to revert to the stock firmware with no success also. I clearly am missing something.
One source of confusion is after I unzip the packages I am left with many files.  When opening Xloader I select one of the files believing that the others will follow.  Nope.
HELP!!
Bill
.


Re: Firmware loading ignorance

Jonas Sanamon
 

Hi Bill,


Unzip, and read the text file that describes which hex file you should use.

Regards
Jonas


Den tis 24 nov. 2020 kl 20:14 skrev Bill Robbins <wa8cdu@...>:

Thanks Jonas.  Can you point me to that?



Re: V6 BFO alignment problems after installing AGC

Jack Hunt
 

Thank you Tim,
I seem to have the coarse BFO alignment ok now. I'm just trying to get the frequency calibration correct now.

73s


Re: Firmware loading ignorance

Evan Hand
 

Bill,
I should also point out that the zip archive has a text file that describes the display hardware that each of the .hex files uses.
FileNameInfo.txt

73
Evan
AC9TU


Re: Firmware loading ignorance

Bill Robbins
 

Thanks Jonas.  Can you point me to that?

On 11/24/2020 1:36 PM, Jonas Sanamon wrote:
Hi Bill,

You should only upload the precompiled .hex file with xloader. Perhaps You downloaded the source code instead?

Regards, Jonas


Den tis 24 nov. 2020 kl 19:18 skrev Bill Robbins <wa8cdu@...>:
I now have my ubitx20 v5 assembled.  I was working fine and I had begun
the alignment process.  Then it occurred to me to load the KD8CEC
firmware rather than going thru alignment twice.

I have loaded sketches previously but it has been sometime.  I followed
the KD8CEC instructions (I thought).  But I get no satisfaction.

So I tried to revert to the stock firmware with no success also. I
clearly am missing something.

One source of confusion is after I unzip the packages I am left with
many files.  When opening Xloader I select one of the files believing
that the others will follow.  Nope.

HELP!!

Bill


Re: Firmware loading ignorance

Evan Hand
 

Bill,
I am most familiar with the KD8CEC firmware and would recommend loading that software using Xloader.  You will need to use the correct version that is in the uBITXV5 folder after you unzip the archive.  The correct file depends on the hardware you have.  I assume that you are using the supplied stock 1602 display.  That file would be UBITXV5_CEC_V1.200_16P.hex.  This also assumes that you have not added the second Nano to do the S meter and other signal processing.

For reference, the archive is here:
https://github.com/phdlee/ubitx/releases/tag/v1.20

you download the zip file and extract the files to a known location.

How to load the file into your uBITX Nano depends on your OS.  For Windows, you first need to work out which com port the uBITX is connected to on your computer.  Then select it after opening Xloader and set the baud to 34800.

Let us know if you need more information and provide us with any error messages that pop up.

73
Evan
AC9TU


Re: uBitx v5 issue

Evan Hand
 

Jerry,

Again, Thank You.  What you state makes sense.  When I figure out how to measure IMD with the tools that I have I will try it on my other v4 uBITX board.

73
Evan
AC9TU


Re: uBitx v5 issue

Jerry Gaffke
 

Evan,

Good to know that your back-to-back diodes present no issues with reception.
Seems a fine solution.  If incoming RF is kept below 4 volts peak-to-peak,
there should be no trouble with Q90 blowing due to Veb-max of 6v being violated.

I would not call the 1n914 obsolete, they still sell them on Mouser.
1n914's are an older part, were not spec'd as tight as the newer 1n4148, but otherwise identical.
I suspect that any parts sold as 1n914's in the last few decades come off the same line
as the 1n4148's, just slapped with different labeling.

>  There was concern about the reverse diode on the base of Q90 having a negative impact on the SSB transmission. 

I'd be surprised if this was an issue, but worth looking at if you have a way to measure IMD.
Transmit RF into Q90 should be down around 100mv rms, so currents through
a silicon diode would be measured in picoamps.
Also, we already have the base-emitter diode in there to cause distortion of large signals, 
adding a 1n4148 going the other way across that junction diode would make it symetrical, 
and may well reduce distortion rather than add to it.

Jerry, KE7ER




On Tue, Nov 24, 2020 at 03:38 AM, Evan Hand wrote:

I have done the back to back diodes on the input to my v4 board and have not noticed any negative effects on the receive capability. 


Re: New PCB available for WA2EBY linear amp #linear-amp

AndyH
 

Hi Ken,

  I like your filter board!  I've had the "it would be cool if the µBITX could change bands on the amp" thought in my head for a while but haven't gotten farther than that.  Nice work!

Leonard - you did more than that.  You've also answered frantic questions from RF noobs that helped them know for sure that their new creation was working correctly.  Thanks again, Sir!

  FWIW, this is the heat sink I'm using.  It was the closest size match I could find to the part WA2EBY specified in his article.  It's 61 x 116.8 x 38.1 mm (L x W x H).  
   https://www.mouser.com/ProductDetail/TDK-Lambda/HAF15T?qs=%2Fha2pyFadujYuVZC2e13mzcrXnoEzMiZDtNhiwH3OfQ%3D

   Andy


On Mon, Nov 23, 2020 at 01:33 PM, Ken K0KV wrote:
Andy, 
Regarding the multi-band LPF board - I needed one that was PC-controllable because I mainly operate remotely (shack is upstairs, PC is in family room).   So I designed my own board, which uses relays to switch the LPF's in and out for each band.  It can be controlled from a simple contact closure (e.g. an Alexa-controlled relay) or via digital outputs from an Arduino. 
 


Also - you're right, I should have mentioned the toroid kit - it's super convenient.  I decided not to buy it because I already had some of the cores on hand.


Re: Firmware loading ignorance

Jonas Sanamon
 

Hi Bill,

You should only upload the precompiled .hex file with xloader. Perhaps You downloaded the source code instead?

Regards, Jonas


Den tis 24 nov. 2020 kl 19:18 skrev Bill Robbins <wa8cdu@...>:

I now have my ubitx20 v5 assembled.  I was working fine and I had begun
the alignment process.  Then it occurred to me to load the KD8CEC
firmware rather than going thru alignment twice.

I have loaded sketches previously but it has been sometime.  I followed
the KD8CEC instructions (I thought).  But I get no satisfaction.

So I tried to revert to the stock firmware with no success also. I
clearly am missing something.

One source of confusion is after I unzip the packages I am left with
many files.  When opening Xloader I select one of the files believing
that the others will follow.  Nope.

HELP!!

Bill


Firmware loading ignorance

Bill Robbins
 

I now have my ubitx20 v5 assembled.  I was working fine and I had begun the alignment process.  Then it occurred to me to load the KD8CEC firmware rather than going thru alignment twice.

I have loaded sketches previously but it has been sometime.  I followed the KD8CEC instructions (I thought).  But I get no satisfaction.

So I tried to revert to the stock firmware with no success also. I clearly am missing something.

One source of confusion is after I unzip the packages I am left with many files.  When opening Xloader I select one of the files believing that the others will follow.  Nope.

HELP!!

Bill


Re: uBitx v5 issue

Bill Cromwell
 

Hi Ted,

I am preparing to replace Q90 in my V3 and I will be installing the diodes. I have used them in other solid state rigs in the past and a couple of time I have had to replace them (two different radios). The usual failure mode is for them to fail-short. It becomes obvious then that they have failed because incoming signals pretty much vanish. In both cases the rest of the radio was preserved. The sacrificial diodes did their job.

I have never had any problems with radios that have those diodes installed. Most of the caveats that have been posted here are *speculation* about what might happen. It hasn't happened. None of the posts have asserted that any problem has actually happened. I have two experiences where the front ends were saved and no experiences where the diodes caused any problems. And that is experience, not speculation.

73,

Bill KU8H

bark less - wag more

On 11/24/20 11:40 AM, Ted via groups.io wrote:
Would the common 1n914 serve the same purpose?   Being as common as it is, etc.
Ted
k3rta


Re: uBitx v5 issue

Evan Hand
 

Ted,
Yes, the 1n914 or equal would work as far as the information that I have found and what I have tried.  I believe that the 1n4148 is a direct replacement for the now obsolete 1n914.

73
Evan
AC9TU


Re: uBitx v5 issue

Ted
 

Would the common 1n914 serve the same purpose?   Being as common as it is, etc.


Ted
k3rta


Re: New PCB available for WA2EBY linear amp #linear-amp

 

Hi,

It does look nice for single band use as it looks like Sunil has added a spot for a single LPF on the amp board.  Probably it's set up for 10m now, but you could choose a lower band as desired.

73,  Mark


Re: uBitx v5 issue

Evan Hand
 

Jerry,
Thank you for the feedback.  It is a good summary of the data that has been presented in this forum as far as I know.  

No one has yet published any data on either the susceptibility to high RF (what is the actual threshold before failure), on the effect of the diode on Q90 to transmission, or back to back diodes on reception. 

There was concern about the reverse diode on the base of Q90 having a negative impact on the SSB transmission.  Has anyone tried that?  If so, it would be good to know if it works with no adverse effects.  

I have done the back to back diodes on the input to my v4 board and have not noticed any negative effects on the receive capability.  I have NOT done any significant testing to verify the before and after results of the diodes, so this is not conclusive of this being a good solution other than one that works at my QTH where the noise floor is very high.  The high noise could mask any of the potential problems that Farhan points out.  NOTE: the noise issue is on all of my rigs that include an Icom 7300, Hermes HL2, QCX+, and an RSP1a as well as 2 v4 and one v5 uBITX.  I have only modified one of my v4 boards to test the effect of the diodes.

I have not had the Q90 failure problem, mainly because I very rigorously only connect one HF rig to an antenna at a time (I do have three HF antennas up).  I do have a 50 watt Kenwood TM-D710G 2m/70cm that I do use at the same time, and so far it has not destroyed any of my uBITX Q90s.  I have also tried to measure the signal strength of the VHF/UHF antenna to the closest HF antenna, and could not get an effective measurement.  I tried that with my oscilloscope.  The sensitivity is only 2mv/division (1x probe setting).  That should have been low enough to measure any signal large enough to overcome the 0.6volt diode threshold.  The measurements would be specific to my QTH and antenna placement.

To sum up my opinion at this point; without more data, I would do one of the diode protection schemes only if you will be using the rig near other high RF transmitters when connected to an antenna, or if you do experience a Q90 failure.  I am still leaning towards the back to back diodes as that is switched out when the uBITX goes into transmit.  This could be modified to a single diode connected as to protect the base to emitter junction, just installed at the switched point like the back to back diodes.

As a side note, the back to back diodes was cited on this reflector (sorry, I do not have the original post), and lead me to further internet research on my part.  I found that the scheme (with variations) have been used to protect receivers quite often for the exact same reason: protecting sensitive components connected to the antenna from strong RF fields.  Here is one of the articles that I found:
http://www.ad5x.com/images/Articles/FrontEndProt.pdf
and another
http://www.na0tc.org/lib/exe/fetch.php?media=technical:rx_protect.pdf
Both use variations on the back to back diodes.  These are only two of the references that I found.


Jerry, again thank you!  Also thanks to Iz and Farhan for sharing their thoughts.  This is how I learn.
73
Evan
AC9TU


Re: uBitx v5 issue

Bob Lunsford
 

Correction: ...a 3/4-in square heat radiator attached to the regulator....

On Monday, November 23, 2020, 10:38:02 PM EST, Bob Lunsford via groups.io <nocrud222@...> wrote:


Don't recall if my V6 had one but I remember seeing a picture of the regulator and it had a about a 3/4-in square heat regulator attached to the regulator. If one is in your parts drawer, I think it would be wise to attach it to the regulator. Or, you could bend up a small strip of aluminum and make one. No real danger of shorting and no need to insulate it from the tab. It would provide peace of mind when the regulator heats up and most of the heat is drawn away and dissipated.

Bob — KK5R

On Monday, November 23, 2020, 5:03:34 PM EST, Curt via groups.io <wb8yyy@...> wrote:


Bill

great you are checking these things as you assemble.  do examine the schematic and you will see what Jerry is citing - funny thing I was once worried as you!  oh yes - when you power up and touch the regulator on the raduino - don't be alarmed when you discover it is quite warm.  and that your BFO calibration may be way off. 

welcome to the global bitx community.  73

curt


Re: uBitx v5 issue

Bob Lunsford
 

Don't recall if my V6 had one but I remember seeing a picture of the regulator and it had a about a 3/4-in square heat regulator attached to the regulator. If one is in your parts drawer, I think it would be wise to attach it to the regulator. Or, you could bend up a small strip of aluminum and make one. No real danger of shorting and no need to insulate it from the tab. It would provide peace of mind when the regulator heats up and most of the heat is drawn away and dissipated.

Bob — KK5R

On Monday, November 23, 2020, 5:03:34 PM EST, Curt via groups.io <wb8yyy@...> wrote:


Bill

great you are checking these things as you assemble.  do examine the schematic and you will see what Jerry is citing - funny thing I was once worried as you!  oh yes - when you power up and touch the regulator on the raduino - don't be alarmed when you discover it is quite warm.  and that your BFO calibration may be way off. 

welcome to the global bitx community.  73

curt

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