Topics

Made Mods to V3 uBitx - no longer transmitting #ubitx-help #v3

Steve - KE0VCD
 

I've completed 3 fixes/modifications to my uBitx v3.  These include:

Make your rig compliant by removing unwanted spurs  http://ubitx.net/spectral-purity/

Make your rig (mostly) compliant by removing unwanted harmonics (same link)

FIX: UNEVEN TX OUTPUT ACROSS BANDS Relay and potentiometer solution (Bill K9HZ  THE N6CNY VERSION)  http://ubitx.net/fix-fix-uneven-tx-output-across-bands/

After completing the mods, the rig is no longer transmitting.  I have tested the new board and believe it is working properly.  As far as I can tell, the new relay switches are working properly.  I've installed and reinstalled the L5 and L7 capacitors.  I've adjusted the new pots in several different ways.  Still nothing. 

Radiuno appears to be functioning properly.  

I fear I've messed up something else in the process. 

What advice can you give me on the best method to debug the board?  I have little experience in modifying and/or building electronics.  

Curt
 

Funny thing, mine is on the bench after different spurious mods with the opposite problem. I can easily remove my 45 MHz added filter mod to see what I did.

Make sure there is no issue with relay orientation,  if misorientation is even possible, or more likely a poor or missing solder connection on a relay pin.  do check more than one band to see if its a particular relay.

Did you try both cw and ssb transmit to see if both are broken?

I presume you mean replacing L5 and L7 toroids with smt inductors. Look visually to insure one doesn't have a solder or other short across it. Yes hard to confirm.

Yes these times require patience.

I know nothing on that pot solution,  yes always best to only introduce one change at a time.

73 curt

 

Is it receiving ?

Raj


At 23-01-20, you wrote:
I've completed 3 fixes/modifications to my uBitx v3.  These include:

Make your rig compliant by removing unwanted spurs  http://ubitx.net/spectral-purity/

Make your rig (mostly) compliant by removing unwanted harmonics (same link)

FIX: UNEVEN TX OUTPUT ACROSS BANDS Relay and potentiometer solution (Bill K9HZ  THE N6CNY VERSION)  http://ubitx.net/fix-fix-uneven-tx-output-across-bands/

After completing the mods, the rig is no longer transmitting.  I have tested the new board and believe it is working properly.  As far as I can tell, the new relay switches are working properly.  I've installed and reinstalled the L5 and L7 capacitors.  I've adjusted the new pots in several different ways.  Still nothing. 

Radiuno appears to be functioning properly. 

I fear I've messed up something else in the process. 

What advice can you give me on the best method to debug the board?  I have little experience in modifying and/or building electronics. 

Dennis Zabawa
 

As a guideline for future mods, do one at a time and thoroughly test each before doing the next.  This minimizes the number of points to check for errors.  As for now, review the steps of each mode until you find the problem.

Steve - KE0VCD
 

Thanks for the response.  

Misorientation of the relays is not possible due to the pin pattern.   I have tried multiple bands.  I don't use cw and don't have any equipment to try it. 

I've visually verified that there isn't a short of the smt inductors.  

I need patience but I need it NOW!!!   lol  patience that is.  I'm not in a hurry on the radio.  

Steve - KE0VCD
 

Yes, it is receiving.  I had to put my antenna back together in order to verify.  Good news, my antenna now is working great!  

Steve - KE0VCD
 

Thanks Dennis.  I'm kicking myself over not doing that.  I considered it but decided against doing it that way.  

What do you mean by reviewing the steps of each mode?

Steve - KE0VCD
 

I've ordered some heated tweezers in order to attempt for a 4th time the placement of the smt inductors.  

Jim WB2LHP in MI
 

Probably not what you want to hear but I would remove/reverse ALL mods and see if you can get back to a working radio...Look for solder bridges, cold solder joints or burnt traces...If you can get back to an original working radio, then you can add the mods back in one at a time and verify each before moving on to the next...Also, make sure you didn't upset the connections between the Raduino and the main board...In my mind, that's where you need to go...GL Jim WB2LHP

Steve - KE0VCD
 

Thanks Jim.  

So you're saying I should have kept the old parts?   :(  

Jim WB2LHP in MI
 

Also, check those SMT inductors you removed for continuity...Make sure they did not open up with all the heating and reheating...

Gordon Gibby
 

For my two cents worth, it’s always easiest if you can get the radio to tell you where the problem is

That may require that you purchase or make some measurements equipment,  but anyway that you can follow a signal through the schematic and see where it’s disappearing will probably zero you in quicker.  

I know this is work, and I know it requires some learning, but that is actually one of the goals of the FCC part 97.1.  

Measurement equipment is cheaper now than at any time in my lifetime.   I can remember as a kid I would sit and read the ARRL handbook, and that still a good idea for beginners. 

Just like when working on cars, the more you know, the easier it is to fix it with less busted knuckles


On Jan 25, 2020, at 17:27, sksshel@... wrote:

Thanks Jim.  

So you're saying I should have kept the old parts?   :(  

Steve - KE0VCD
 

Jim,

Each time I've used new inductors.   

Gordon, 

I enjoy learning new things.  Can you point me to something online that describes what I need to do?

Richard Spohn
 

One last observation: I have been a ham for 5 decades and hold an
Extra. I love learning about how electronics work, and I enjoy
building things. That said, I have also done my share of "appliance
buying". There are hundreds of radio products that are sold as
plug-and-play, with full warrantees if even one component is
defective. I do not think it is productive to assume a "you better
learn how to build things or you're not a ham" stance. There is room
in ham radio for hams who desire to buy something and have it work out
of the box. No prejudice against them. -- Rich

On 1/25/20, Gordon Gibby <docvacuumtubes@...> wrote:
For my two cents worth, it’s always easiest if you can get the radio to tell
you where the problem is

That may require that you purchase or make some measurements equipment, but
anyway that you can follow a signal through the schematic and see where it’s
disappearing will probably zero you in quicker.

I know this is work, and I know it requires some learning, but that is
actually one of the goals of the FCC part 97.1.

Measurement equipment is cheaper now than at any time in my lifetime. I
can remember as a kid I would sit and read the ARRL handbook, and that still
a good idea for beginners.

Just like when working on cars, the more you know, the easier it is to fix
it with less busted knuckles
On Jan 25, 2020, at 17:27, sksshel@... wrote:

Thanks Jim.

So you're saying I should have kept the old parts? :(


Andy_501
 

Element14 Newark electronics has useful picoscope at very reasonable price $150 Cdn if you have probes $180 if you need kit with probes. 2204 A is model SKU I believe on Cdn site. Only 10 MHz BW but that is much better than nothing when doing initial go-no-go half split troubleshooting.

Local hardware big box stores often have great deals on DVMs with measurement capabilities including capacitors and inductors for under $50.

a laptop and an audio editor like audacity (windows, mac, & linux platforms) can serve to do a lot of audio signal testing for troubleshooting and there are web sites that you can set the freq and generate specific tone freqs and save in broadcast wav formats. Then use audacity to set levels and times so it doesn't exceed safe digital aud limits like 1 VAC P-P to prevent clipping and distorion. Of course some surplus test gear from an actual shop would be preferable.



On 2020-01-25 4:29 p.m., Gordon Gibby wrote:
For my two cents worth, it’s always easiest if you can get the radio to tell you where the problem is

That may require that you purchase or make some measurements equipment,  but anyway that you can follow a signal through the schematic and see where it’s disappearing will probably zero you in quicker.  

I know this is work, and I know it requires some learning, but that is actually one of the goals of the FCC part 97.1.  

Measurement equipment is cheaper now than at any time in my lifetime.   I can remember as a kid I would sit and read the ARRL handbook, and that still a good idea for beginners. 

Just like when working on cars, the more you know, the easier it is to fix it with less busted knuckles


On Jan 25, 2020, at 17:27, sksshel@... wrote:

Thanks Jim.  

So you're saying I should have kept the old parts?   :(  

Bill Howard
 

I'll see your five decades and up you to my six decades. I have built rigs from scratch, both tube and semiconductor, the last build being the receiver with digital readout featured in the 1976 ARRL handbook. I also have enjoyed using rigs off the shelf, like my latest IC-7300. My point is the wide variety available to us as hams, and the learning never stops. Enjoy while you can. WB3V  



Bill Howard


-------- Original message --------
From: Richard Spohn <wb2gxm@...>
Date: 1/25/20 5:58 PM (GMT-05:00)
To: BITX20@groups.io
Subject: Re: [BITX20] Made Mods to V3 uBitx - no longer transmitting #ubitx-help #v3

One last observation:  I have been a ham for 5 decades and hold an
Extra.  I love learning about how electronics work, and I enjoy
building things.  That said, I have also done my share of "appliance
buying".  There are hundreds of radio products that are sold as
plug-and-play, with full warrantees if even one component is
defective.  I do not think it is productive to assume a "you better
learn how to build things or you're not a ham" stance.  There is room
in ham radio for hams who desire to buy something and have it work out
of the box.  No prejudice against them. -- Rich

On 1/25/20, Gordon Gibby <docvacuumtubes@...> wrote:
> For my two cents worth, it’s always easiest if you can get the radio to tell
> you where the problem is
>
> That may require that you purchase or make some measurements equipment,  but
> anyway that you can follow a signal through the schematic and see where it’s
> disappearing will probably zero you in quicker.
>
> I know this is work, and I know it requires some learning, but that is
> actually one of the goals of the FCC part 97.1.
>
> Measurement equipment is cheaper now than at any time in my lifetime.   I
> can remember as a kid I would sit and read the ARRL handbook, and that still
> a good idea for beginners.
>
> Just like when working on cars, the more you know, the easier it is to fix
> it with less busted knuckles
>> On Jan 25, 2020, at 17:27, sksshel@... wrote:
>>
>> Thanks Jim.
>>
>> So you're saying I should have kept the old parts?   :(
>>
>
>
>
>



Jim WB2LHP in MI
 

Hindsight is 20/20...

On Sat, Jan 25, 2020 at 5:27 PM <sksshel@...> wrote:
Thanks Jim.  

So you're saying I should have kept the old parts?   :(  

Christopher Miller
 

Depending on where you live you might have a local hacker space. Xerocraft here in Tucson has a couple of professional oscilloscopes, microscopes, smd tools, etc. 

KF4FTR

On Sat, Jan 25, 2020 at 4:02 PM Andy_501 <andrew.webb.501.ve4per@...> wrote:

Element14 Newark electronics has useful picoscope at very reasonable price $150 Cdn if you have probes $180 if you need kit with probes. 2204 A is model SKU I believe on Cdn site. Only 10 MHz BW but that is much better than nothing when doing initial go-no-go half split troubleshooting.

Local hardware big box stores often have great deals on DVMs with measurement capabilities including capacitors and inductors for under $50.

a laptop and an audio editor like audacity (windows, mac, & linux platforms) can serve to do a lot of audio signal testing for troubleshooting and there are web sites that you can set the freq and generate specific tone freqs and save in broadcast wav formats. Then use audacity to set levels and times so it doesn't exceed safe digital aud limits like 1 VAC P-P to prevent clipping and distorion. Of course some surplus test gear from an actual shop would be preferable.



On 2020-01-25 4:29 p.m., Gordon Gibby wrote:
For my two cents worth, it’s always easiest if you can get the radio to tell you where the problem is

That may require that you purchase or make some measurements equipment,  but anyway that you can follow a signal through the schematic and see where it’s disappearing will probably zero you in quicker.  

I know this is work, and I know it requires some learning, but that is actually one of the goals of the FCC part 97.1.  

Measurement equipment is cheaper now than at any time in my lifetime.   I can remember as a kid I would sit and read the ARRL handbook, and that still a good idea for beginners. 

Just like when working on cars, the more you know, the easier it is to fix it with less busted knuckles


On Jan 25, 2020, at 17:27, sksshel@... wrote:

Thanks Jim.  

So you're saying I should have kept the old parts?   :(  

Jim WB2LHP in MI
 

Nothing specific but there is a ton of good information online covering all kinds of theory and troubleshooting techniques...

Attached is the block diagram of the V3 radio...If your receiver is working you can isolate what sections are working and which ones are not...That will help narrow things down...

On Sat, Jan 25, 2020 at 5:36 PM <sksshel@...> wrote:
Jim,

Each time I've used new inductors.   

Gordon, 

I enjoy learning new things.  Can you point me to something online that describes what I need to do?

Jim WB2LHP in MI
 

You've embarked on a path of learning...Along that path there will be successes and disasters...There is a delicate balance between investment and reward but I would look at this now as a learning experience...You may or may not be able to recover the radio but your understanding of how things work will improve dramatically...There isn't one of us out there who hasn't blown something up at one time or another...GL Jim WB2LHP