Date   

Re: Low sensitivity

ajparent1/kb1gmx <kb1gmx@...>
 

Bruce,

The MFJ is handy but its far from calibrated in frequency.  

Allison
---------------------------------
No direct email, it goes to bit bucket due address harvesting in groups.IO


Low sensitivity

Bruce Morrell
 

Fellow Utix v6 users.  I have a new v6 radio I am trying to determine if it is properly working.  I am unable to pick up wwv signals so I am calibrating using a mfj 259b as a signal source.  I have gone through the calibration process to the best of my knowledge.
Next I started checking voltage in the recv circuit . q20,21,22,40,41,42 and 70 check out.  Q74 has o dc volts on all leads.  Is this correct???

Thanks for your responses. Bruce


Re: Building a 12V Supply Board

Dale Parfitt
 

The ‘clacks’ are most likely radiated noise and not conducted. This is normal.

 

Dale W4OP

 

From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of peter.mccracken@...
Sent: Thursday, July 9, 2020 1:09 PM
To: BITX20@groups.io
Subject: Re: [BITX20] Building a 12V Supply Board

 

It's definitely coming from the mains, if I switch off the soldering iron I get a <clack> on the audio of the radio, if I switch off the main light switch in the room I get an extremely loud <CLACK>. I have a PS30SWII switching power supply, I was considering doing this on its mains lead.

http://www.m0nwk.co.uk/mains-electricity-filter-for-emc-noise-reduction/

... which looks encouraging, but I also want to "filter" more on the incoming 12v. I also have the problem of "clicks" when using the encoder and you can hear "noise" when pressing the touch screen.

More info is that I will install a Nextion 5" screen at the weekend along with a second nano. I have some info on how to reduce the noise from the Nextion.

Evan, thanks for the info on calculating the required resistor size, that all makes sense as does the comment about the disc capacitor.


Re: Building a 12V Supply Board

Peter McCracken
 

It's definitely coming from the mains, if I switch off the soldering iron I get a <clack> on the audio of the radio, if I switch off the main light switch in the room I get an extremely loud <CLACK>. I have a PS30SWII switching power supply, I was considering doing this on its mains lead..

http://www.m0nwk.co.uk/mains-electricity-filter-for-emc-noise-reduction/

... which looks encouraging, but I also want to "filter" more on the incoming 12v. I also have the problem of "clicks" when using the encoder and you can hear "noise" when pressing the touch screen.

More info is that I will install a Nextion 5" screen at the weekend along with a second nano. I have some info on how to reduce the noise from the Nextion.

Evan, thanks for the info on calculating the required resistor size, that all makes sense as does the comment about the disc capacitor.


Re: Building a 12V Supply Board

Bill Cromwell
 

Hi,

I would agree that a noisy power supply should be tamed at the power supply. I will suggest looking at the schematics of PC switching power supplies and focus on the filtering circuits that introduce the AC supply current from your electric energy company - aka your power mains. There are capacitors and chokes in that filter. I had a problem with one a number of years ago and could not have that computer turned on while using the radio. That is really inconvenient when we want to run digital modes:)

I found those filter parts had been omitted to save a few pennies. The circuit board had the traces and the mounting points and the silk screen for the parts. It had jumpers to carry AC power past those places and no filter parts. I installed the needed parts and the computer was then usable with the radio.

I hope this helps somebody.

73,

Bill KU8H

bark less - wag more

On 7/9/20 12:28 PM, Evan Hand wrote:
Peter,
Before you go through the trouble of building in the "noise" filter, I would first verify that the noise is coming from the 12 supply.  The best way to do that is to test the noise level on battery power.  You do not need to transmit, so any 12v battery capable of supplying 250 to 300 ma for a short time should do.  I have used a car jumper battery that I have and found little to no difference in the noise level on battery power vs mains supplied through either of my TexPower 13.8volt switching supplies. The noise is coming from the antenna in my neighborhood caused by QRM and high QRN noise levels on the air in general.
With the above understanding, I will make some suggestions for R2 to reduce the power dissipation of the 7805 regulator.   That does depend on the total current that you will need from the regulator, and THAT depends on what you have planned to add onto the rig that will need 5 volts.  If you add up the power requirements of all of the devices on the stock rigs, the total current is much less than 200ma, more like 120 ma (approximate, as I have not done all of the spec sheet validations  I did look up the stock version 6 2.8" display and that has a max of 80ma).  Then you have the minimum voltage that the 7805 needs to regulate to 5 volts.  I use 3 volts to get some safety margin.  That means you need to supply 5 + 3 = 8volts minimum at maximum current.  If the input voltage is truly 12 volts, and you want 8 volts to the regulator minimum at 200ma, and you need a 4volt drop at 200 ma, then 4/.2=20ohms.  That resistor will need to dissipate 4*0.2 = 0.8 watts. All of these calculations are DC values, so the simple E=IR and P=EI and the transforms work.
For my rigs, I am adding second Nanos, larger displays with built-in GUI processors, and signal processors, so I have upped the max current to <1 amp (the maximum that the 7805 provided by HFSignals can regulate) and added other safety margins to get 4 ohms at 4 watts.  Were I to do it again, I would have added a second 7805 to supply the auxiliary equipment and not modified the Raduino board.
In general, the stock setup works well, and no changes are needed. Adding a heatsink to the regulator can help if you are going to operate in high ambient temperatures.
The other comment that I would make is that if you find you have RF noise from the power supply, then you will need to add capacitors to filter the higher frequency.  Something like a 0.1 to 0.01 uF ceramic disc.  The 470uF will not filter higher frequency stuff.  There is too high of internal resistance at RF in electrolytic capacitors.  You may also be better off to add an RF choke instead of the resistor.  I will let someone more knowledgable on that subject to make a true recommendation.
The above are my thoughts and should be verified before you take action on them.  I do make mistakes at times.
73
Evan
AC9TU


Re: Building a 12V Supply Board

Evan Hand
 

Peter,

Before you go through the trouble of building in the "noise" filter, I would first verify that the noise is coming from the 12 supply.  The best way to do that is to test the noise level on battery power.  You do not need to transmit, so any 12v battery capable of supplying 250 to 300 ma for a short time should do.  I have used a car jumper battery that I have and found little to no difference in the noise level on battery power vs mains supplied through either of my TexPower 13.8volt switching supplies. The noise is coming from the antenna in my neighborhood caused by QRM and high QRN noise levels on the air in general.

With the above understanding, I will make some suggestions for R2 to reduce the power dissipation of the 7805 regulator.   That does depend on the total current that you will need from the regulator, and THAT depends on what you have planned to add onto the rig that will need 5 volts.  If you add up the power requirements of all of the devices on the stock rigs, the total current is much less than 200ma, more like 120 ma (approximate, as I have not done all of the spec sheet validations  I did look up the stock version 6 2.8" display and that has a max of 80ma).  Then you have the minimum voltage that the 7805 needs to regulate to 5 volts.  I use 3 volts to get some safety margin.  That means you need to supply 5 + 3 = 8volts minimum at maximum current.  If the input voltage is truly 12 volts, and you want 8 volts to the regulator minimum at 200ma, and you need a 4volt drop at 200 ma, then 4/.2=20ohms.  That resistor will need to dissipate 4*0.2 = 0.8 watts.  All of these calculations are DC values, so the simple E=IR and P=EI and the transforms work.

For my rigs, I am adding second Nanos, larger displays with built-in GUI processors, and signal processors, so I have upped the max current to <1 amp (the maximum that the 7805 provided by HFSignals can regulate) and added other safety margins to get 4 ohms at 4 watts.  Were I to do it again, I would have added a second 7805 to supply the auxiliary equipment and not modified the Raduino board.

In general, the stock setup works well, and no changes are needed.  Adding a heatsink to the regulator can help if you are going to operate in high ambient temperatures.  

The other comment that I would make is that if you find you have RF noise from the power supply, then you will need to add capacitors to filter the higher frequency.  Something like a 0.1 to 0.01 uF ceramic disc.  The 470uF will not filter higher frequency stuff.  There is too high of internal resistance at RF in electrolytic capacitors.  You may also be better off to add an RF choke instead of the resistor.  I will let someone more knowledgable on that subject to make a true recommendation.

The above are my thoughts and should be verified before you take action on them.  I do make mistakes at times.
73
Evan
AC9TU


Re: construction

Evan Hand
 

I believe that Sarma has hit on the most probable cause.  I have had issues with the antenna pins coming loose, so the red power lead to the mainboard is a good candidate.  If you add the leakage current of the finals to the 87 ma that I measured you get the 90ma.  Could also be just a bad connection to the pin in the connector.  If you have a pin you could measure the red wire connection to see if there is 12 volts on it.

73
Evan
AC9TU


Building a 12V Supply Board

Peter McCracken
 


Hi all,

I want to build a dedicated power supply board mounted to the back of the case and remove the regulator that is currently on the raduino, I also want to try to "clean" as much noise as possible from the supply whilst doing this. I only have rudimentary knowledge of this stuff but the below is my attempt at designing something for this. The idea is to clean up the 12V supply before connecting it to the ubitx mainboard and also use a resistor to drop the voltage into the regulator somewhat before feeding that into the Raduino. I am not sure what value would be good for R2. I would be grateful for any suggestion as to how I could do this better.



Best regards, Peter.


Re: construction

MVS Sarma
 

Appears loose pins on the 3 wire power plug. 
Especially if  Red wire is loose  and  some leakage current on the brown Tx wire somewhere could be an answer for 3.5mA

Sarma vu3zmv

On Thu, 9 Jul 2020, 5:16 pm Ray Lenthall VK3JH, <vk3jh@...> wrote:

Hi Evan

 

Thanks for your reply.  I have checked the voltage form the power supply and it is 12.3 v.  I bypassed the diode in case there was a problem there but still came up with the same result of 3.5ma rather than the 90ma.

 

73

 

Ray

 

From: BITX20@groups.io <BITX20@groups.io> On Behalf Of Evan Hand
Sent: Thursday, 9 July 2020 4:01 PM
To: BITX20@groups.io
Subject: Re: [BITX20] construction

 

Ray,

There are 7 2n3904 transistors that should be on in a linear bias plus the LM386 audio amp when in receive.  If you have wired the power correctly (the RED wire is the +12volts to everything EXCEPT the PA)  it should read 90+ma.  I would check your power wiring as a start.  I would also check the power supply to verify that it is providing 12volts.

The readings are without the Raduino connected, per the original wireup instructions.  The PA bias adjustments come later and will add another 200ma + the Raduino current requirements to the readings. 

My v5 is buried in a case with a 3.5" Nextion screen, AGC, and an outboard audio amp, so it is not easy for me to get to the readings from that board for comparison. As stated in the first paragraph above, you most likely have a power supply/wiring issue.

73
Evan
AC9TU

73
Evan
AC9TU


Re: construction

Evan Hand
 

Not sure I understand bypassing the diode.  Per the wire up instructions, the supplied diode is to be used for reverse voltage protection, and if you wired it per the instructions then bypassing the diode would short out the supply.

I would verify that you are getting the 12volts to R18, R38, R52, and R71.  These are the active stages with power when the Raduino is disconnected.  The voltage drops that I got across them are:
R18 = .4 volts  so that is drawing 40ma
R38 = .4 volts so that is drawing 40 ma
R52 = .52 volts so that is drawing 2.4 ma
R71 = .46 volts so that is drawing 4.6 ma

Total = 87 ma close to the 90 ma specified.  There could be other sections that make up the last 3 ma or it could be the meter or resistor value differences.

Also, check that the power connector is plugged in correctly and not offset by a pin or in reversed. 

I really do not know what could cause these symptoms, other than an open on the board or wiring.  I have not seen, nor read of this type of behavior.  

Happy hunting!
73
Evan
AC9TU


Re: construction

Ray Lenthall VK3JH
 

Hi Evan

 

Thanks for your reply.  I have checked the voltage form the power supply and it is 12.3 v.  I bypassed the diode in case there was a problem there but still came up with the same result of 3.5ma rather than the 90ma.

 

73

 

Ray

 

From: BITX20@groups.io <BITX20@groups.io> On Behalf Of Evan Hand
Sent: Thursday, 9 July 2020 4:01 PM
To: BITX20@groups.io
Subject: Re: [BITX20] construction

 

Ray,

There are 7 2n3904 transistors that should be on in a linear bias plus the LM386 audio amp when in receive.  If you have wired the power correctly (the RED wire is the +12volts to everything EXCEPT the PA)  it should read 90+ma.  I would check your power wiring as a start.  I would also check the power supply to verify that it is providing 12volts.

The readings are without the Raduino connected, per the original wireup instructions.  The PA bias adjustments come later and will add another 200ma + the Raduino current requirements to the readings. 

My v5 is buried in a case with a 3.5" Nextion screen, AGC, and an outboard audio amp, so it is not easy for me to get to the readings from that board for comparison. As stated in the first paragraph above, you most likely have a power supply/wiring issue.

73
Evan
AC9TU

73
Evan
AC9TU


Re: construction

Evan Hand
 

Ray,

There are 7 2n3904 transistors that should be on in a linear bias plus the LM386 audio amp when in receive.  If you have wired the power correctly (the RED wire is the +12volts to everything EXCEPT the PA)  it should read 90+ma.  I would check your power wiring as a start.  I would also check the power supply to verify that it is providing 12volts.

The readings are without the Raduino connected, per the original wireup instructions.  The PA bias adjustments come later and will add another 200ma + the Raduino current requirements to the readings. 

My v5 is buried in a case with a 3.5" Nextion screen, AGC, and an outboard audio amp, so it is not easy for me to get to the readings from that board for comparison. As stated in the first paragraph above, you most likely have a power supply/wiring issue.

73
Evan
AC9TU

73
Evan
AC9TU


Re: construction

vk3jh@...
 

Hi Ted

 

Thanks for the reply.  No the Raduino was not connected the picture in the documents doesn’t have it connected

 

Regards

 

Ray

 

From: BITX20@groups.io <BITX20@groups.io> On Behalf Of Ted via groups.io
Sent: Thursday, 9 July 2020 11:24 AM
To: BITX20@groups.io
Subject: Re: [BITX20] construction

 

Hi, Ray.

 

Is the Raduino connected?

 

 

 

 

Ted


Re: construction

Paul
 

That's what it should read when the finals have had their bias adjusted iirc


On Thu, 9 Jul. 2020, 10:28 am , <vk3jh@...> wrote:
Hi I purchased a V5 last year and am only now starting to put it together. I have wired up the DC power plug as per the instructions and the instructions tell me if I apply 12v it should draw between 90 and 110 ma.  Mine draws 3.5ma. Can anyone give me some clues.  Many thanks.
Ray  VK3JH


Re: R1.4.0 Software Release #ubitx #nano #v6 #ubitxv6

Reed N
 

Yeah, I don't know what bloat was added, but there's a reason I called out the specific IDE version in the Readme file :)


Reed


Re: construction

Ted
 

Hi, Ray.

Is the Raduino connected?




Ted


construction

vk3jh@...
 

Hi I purchased a V5 last year and am only now starting to put it together. I have wired up the DC power plug as per the instructions and the instructions tell me if I apply 12v it should draw between 90 and 110 ma.  Mine draws 3.5ma. Can anyone give me some clues.  Many thanks.
Ray  VK3JH


Re: R1.4.0 Software Release #ubitx #nano #v6 #ubitxv6

Peter McCracken
 

All compiles fine under 1.8.9... the updated libs in 1.8.13 seem to cause bloating...


Re: R1.4.0 Software Release #ubitx #nano #v6 #ubitxv6

Peter McCracken
 

What version of Arduino are people using to compile this ?

Thanks!


Re: D hole plate to fit SO-239 bulkhead hole - SO-239 to BNC conversion

ajparent1/kb1gmx <kb1gmx@...>
 

Dale,

Correct save for NOS abounds and also poor quality copies.
Its more be wary and careful.
 
Allison
---------------------------------
No direct email, it goes to bit bucket due address harvesting in groups.IO