Date   
Re: Encoder knob (with a nod to knobs in general) #3d_printing #parts #ubitx

Martin KM6TCD
 

I'm working on a copper plated, Slinky hoop antenna.  Yhe copper plating makes it a better radiator and the hoop is only 5 feet in diameter. Just what the doctor ordered for places with all those crazy rules and regulations. I'll post more when I've finished it.
 
73
KM6TCD

 
Sent: Thursday, December 20, 2018 at 11:23 AM
From: "David Negaard" <draagen@...>
To: BITX20@groups.io
Subject: [BITX20] Encoder knob (with a nod to knobs in general) #ubitx #3d_printing #parts
While waiting for time to finish building my uBITX (and a suitable antennal—gotta love condo living!),

Re: Ubitx microphony

Bob Lunsford <nocrud222@...>
 

The usual method to locate a microphonic device problem area
is to use a small stiff non-metalic brush and sweep the board in
small passes and this tends to show the general area. Then I have
used a drinking straw and tapped lightly the components in that
general area. In a way, a microphonic problem is the easy one to
fix because locating the problem does not require diagnostics of
any electronic circuits with a 'scope, etc.

Some components can be microphonic but all things considered,
I would guess it's a bad solder joint. Suspect this first. If you see
some joints with a magnifying glass that look "frosty" or granular,
touch them with the tip of a hot soldering iron AFTER turning off
the power, of course. This usually is the fix for a bad joint. Some
bad joints are hard to detect, though.

Bad solder joints are not all that uncommon. On the BitX boards,
considering that they are flow soldered, suspect the wires connected
to the board first. However, don't forget the components on the front
panel.

Please let us know what you find. This falls in the unique list of what
can be wrong with a radio.

Bob — KK5R

--------------------------------------------

On Thu, 12/20/18, Peter Russell <peter.russell@...> wrote:

Subject: Re: [BITX20] Ubitx microphony
To: BITX20@groups.io
Date: Thursday, December 20, 2018, 11:00 AM

When I say "microphony"
I mean that the circuit boards are acting as a
microphone - any slight tap on the case can be
heard loudly in the phones.
I haven't
tried it on transmit yet, so I don't know whether it
will be a
problem there also.
I'm sure I've seen reference to it
somewhere but I'm not sure where.
Any
ideas will be welcome.

Peter. G8FWY


On 20/12/2018 15:05, iz oos
wrote:
> What do you mean exactly with
'bit' of microphone? If you refer to low
> average SSB output, I replaced to add
another resistor (47ohm)in
> parallel to
R63 and worked nicely. However late November Barry Underwood

> suggested to use a VOGAD. So I have
just made (I still need to test it)
>
another external box with that compressor to use also with
other SSB
> QRPs, like ILER. I have a
mil surplus radio that use the VOGAD and I
> have always been impressed by it, as you
can just whisper and have a lot
> of
output. See the attached file made by Barry.
>
>
> Il 20/dic/2018 12:35, "Peter
Russell" <peter.russell@...

> <mailto:peter.russell@...>>
ha scritto:
>
>   
Hello from a newbie!
>    I've
just completed the build of my uBITX and I have to say,
I'm
>    impressed!
>    Just one little niggle - and I'm
sure I've seen it mentioned
>   
somewhere but I can't remember where - I seem to have a
bit of
>    microphony. Can anyone
point me in the right direction?
>   
Thanks.
>    Peter, G8FWY.
>
>    ---
>    This email has been checked for
viruses by AVG.
>    https://www.avg.com
>

>
>
>
>

Re: Ubitx microphony

Bob Lunsford <nocrud222@...>
 

Yes. Forgot this. Best check the toroids first since they are
not fixed mechanically to the boards except through their
leads so they can move.

Bob — KK5R

--------------------------------------------

On Thu, 12/20/18, VE3MIC via Groups.Io <ve3mic=yahoo.com@groups.io> wrote:

Subject: Re: [BITX20] Ubitx microphony
To: BITX20@groups.io
Date: Thursday, December 20, 2018, 11:05 AM


Most likely the torroid chokes.. Hot melt glue
or wax them in place.73 de Mike






On Thursday, December 20, 2018, 11:01:00
a.m. GMT-5, Peter Russell
<peter.russell@...> wrote:





When I say
"microphony" I mean that the circuit boards are
acting as a
microphone - any slight tap on
the case can be heard loudly in the phones.
I haven't tried it on transmit yet, so I
don't know whether it will be a
problem
there also.
I'm sure I've seen
reference to it somewhere but I'm not sure where.
Any ideas will be welcome.

Peter. G8FWY


On 20/12/2018 15:05, iz oos
wrote:
> What do you mean exactly with
'bit' of microphone? If you refer to low
> average SSB output, I replaced to add
another resistor (47ohm)in
> parallel to
R63 and worked nicely. However late November Barry Underwood

> suggested to use a VOGAD. So I have
just made (I still need to test it)
>
another external box with that compressor to use also with
other SSB
> QRPs, like ILER. I have a
mil surplus radio that use the VOGAD and I
> have always been impressed by it, as you
can just whisper and have a lot
> of
output. See the attached file made by Barry.
>
>
> Il 20/dic/2018 12:35, "Peter
Russell" <peter.russell@...

> <mailto:peter.russell@...>>
ha scritto:
>
>   
Hello from a newbie!
>    I've
just completed the build of my uBITX and I have to say,
I'm
>    impressed!
>    Just one little niggle - and I'm
sure I've seen it mentioned
>   
somewhere but I can't remember where - I seem to have a
bit of
>    microphony. Can anyone
point me in the right direction?
>   
Thanks.
>    Peter, G8FWY.
>
>    ---
>    This email has been checked for
viruses by AVG.
>    https://www.avg.com
>
>
>
>
>

Re: UbitX build questions

Bob Lunsford <nocrud222@...>
 

Just one note about using a CB microphone. They are
usually dynamic which means they are like a speaker and
would look like a short to the mic input. If you want to use
one of these experimentally, put an isolating capacitor in the
mic input line so it will not short out the line. Also, if you have
a choice, use a high impedance mic ir maybe a small
transformer to make a low impedance mic look like a high
impedance mic. All this is experimental... But the little eletret
element supplied with the radio can be substituted for the mic
element in the CB mic just as easily. Put it in a cut-out piece
of styrofoam made to fit the old mic's shell and connect the
eletred to the designated wires that connect tot the radio.

For a cable, I bought a stereo-to-stereo cable at Dollar Tree
and cut off one end and used this for the mic cable. A proper
cable was not available here so I used what was for me the
most convenient.

Plug-N-chug is the name of the game, sometimes. It's like the
old Murphy's Law: We may not have time to do it right but we
can always find time to do it over.

Bob — KK5R

--------------------------------------------

On Thu, 12/20/18, Mark Vincett <kd2qar@...> wrote:

Subject: Re: [BITX20] UbitX build questions
To: BITX20@groups.io
Date: Thursday, December 20, 2018, 3:18 PM

I had/have
the same question and stared at images and combed the web
quite a bit trying to figure out what to do.My
conclusion (thus far) is that there are too may mic
configurations out there, so it appears to have been left
intentionally vague.I think I identified at least
8 different variations of 4 pin mic wiring by different
manufacturers.I am still, slowly, assembling my
uBitx and haven't started assembling the mic yet but, I
think you will need to study the mic and the photos to
determine which wires in the mic match the function of the
wires in the uBitx.In my case I found an old CB
radio mic in a junk box in the barn that I plan to attempt
to wire to the connector provided in the kit if I can map
the wires into the mic to the three connections in the
uBitx.
This
doesn't necessarily answer the question you have but it
might save you some time searching for an answer that may
not exist in this case.
-Mark
On Thu, Dec 20, 2018 at 2:27 PM dey <deyoung1@...>
wrote:










First
of all, let me apologize for asking what will
be (hopefully) simple questions.  This is the
second kit radio that I have assembled and the first one
with voice capabilities.  My other radios are all
CW.  Which is fine for me.

I just
received the UbitX (v4) and the assembly kit (case and other
parts).  This version includes a mini PCB that hold
the three (03) jacks for the front panel as well as the mic
and speaker connection.  I have managed to get
everything assembled except wiring the round, 4 pin mic
jack.

I
cannot tell which color wire goes to which
pin. 
Any suggestions?

One of
the reasons I purchased this radio was the ability to
“hack” the code.  But I don’t see any
USB (or other) port to use accessing
the Arduino.  Any
suggestions?

I have
a 47 year background in software development so playing in
the Arduino will be fun.

Any
help is appreciated.

Derrick/w4dey








--
----------------------------------------------
     ^
   /   \     Mark
Vincett
 
/___\   KD2QAR
 /    |   \  
      |       
ME --> GA '92 
----------------------------------------------

Re: Encoder knob (with a nod to knobs in general) #3d_printing #parts #ubitx

Lee
 

Very nice.   I wish I new something about Fusion 360.   I've been thinking of getting a Prusa 3D printer with my income tax return.
--
Lee - N9LO  "I Void Warranties"

 

Re: Encoder knob (with a nod to knobs in general) #3d_printing #parts #ubitx

David Negaard
 

Lee, I'm largely self-taught...I've been learning it as I teach intermediate and high school students how to use the tools available in this amazing age.

Just this week I learned enough to model and design an enclosure for my uBITX that can be cut and folded out of a single sheet of aluminum, even though I am unwilling to keep it simple. I'll cut it on a CNC router, fold it, and rivet or weld it.

--
David Negaard
C: (808) 214-8919
“Man is most nearly himself when he achieves the seriousness of a child at play.” –Heraclitus

On Dec 20, 2018, at 2:56 PM, Lee <mr.olson@...> wrote:

Very nice.   I wish I new something about Fusion 360.   I've been thinking of getting a Prusa 3D printer with my income tax return.
--
Lee - N9LO  "I Void Warranties"

 

Re: Encoder knob (with a nod to knobs in general) #3d_printing #parts #ubitx

Tony Frey
 

Nice, are you going to post your file anywhere?

Acta non Verba
 


From: bitx20@groups.io on behalf of David Negaard <draagen@...>
Sent: Thursday, December 20, 2018 8:31 PM
To: bitx20@groups.io
Subject: Re: [BITX20] Encoder knob (with a nod to knobs in general) #ubitx #3d_printing #parts
 
Lee, I'm largely self-taught...I've been learning it as I teach intermediate and high school students how to use the tools available in this amazing age.

Just this week I learned enough to model and design an enclosure for my uBITX that can be cut and folded out of a single sheet of aluminum, even though I am unwilling to keep it simple. I'll cut it on a CNC router, fold it, and rivet or weld it.

--
David Negaard
C: (808) 214-8919
“Man is most nearly himself when he achieves the seriousness of a child at play.” –Heraclitus

On Dec 20, 2018, at 2:56 PM, Lee <mr.olson@...> wrote:

Very nice.   I wish I new something about Fusion 360.   I've been thinking of getting a Prusa 3D printer with my income tax return.
--
Lee - N9LO  "I Void Warranties"

 

Re: WSJT-X for uBITX using LINUX

Mark M
 

Hi Brad...

Thanks for the reply. My settings screen looks exactly like yours. What firmware version are you running on the uBitX? I'm on CEC 1.1. The hamlib version looks to be 3.1 which I think is the latest.

I upgraded Ubuntu to 18.10 but no joy. It works fine talking to my Icom 706 so I don't think it's a systems issue. I even fired up Windoze 10 and installed WSXT-X 2.0 and it does the same thing. I'm beginning to suspect a uBitX firmware issue...whatever command it's sending, the uBitX doesn't understand, or misinterprets.

Interestingly, the uBitX switches VFOs when I try the Test despite the error msg. Very strange...I wonder why it's telling it to switch VFOs?

I'll attach some screenshots. 

73...   Mark   AA7TA

Re: Encoder knob (with a nod to knobs in general) #3d_printing #parts #ubitx

David Negaard
 

Hadn't really thought about it, but can. Wondering what file format would be most suitable, not to mention where...

.STEP files can be opened in many CAD programs, but might lose the sheet metal features available in Fusion 360. Could also include a .DFX for the flat pattern. Files for knobs and such (things to 3D print) can be .STL files, which is a standard for slicing programs.

--
David Negaard
C: (808) 214-8919
“Man is most nearly himself when he achieves the seriousness of a child at play.” –Heraclitus

On Dec 20, 2018, at 5:10 PM, Tony Frey <Tfrey326@...> wrote:

Nice, are you going to post your file anywhere?

Acta non Verba
 

From: bitx20@groups.io on behalf of David Negaard <draagen@...>
Sent: Thursday, December 20, 2018 8:31 PM
To: bitx20@groups.io
Subject: Re: [BITX20] Encoder knob (with a nod to knobs in general) #ubitx #3d_printing #parts
 
Lee, I'm largely self-taught...I've been learning it as I teach intermediate and high school students how to use the tools available in this amazing age.

Just this week I learned enough to model and design an enclosure for my uBITX that can be cut and folded out of a single sheet of aluminum, even though I am unwilling to keep it simple. I'll cut it on a CNC router, fold it, and rivet or weld it.

--
David Negaard
C: (808) 214-8919
“Man is most nearly himself when he achieves the seriousness of a child at play.” –Heraclitus

On Dec 20, 2018, at 2:56 PM, Lee <mr.olson@...> wrote:

Very nice.   I wish I new something about Fusion 360.   I've been thinking of getting a Prusa 3D printer with my income tax return.
--
Lee - N9LO  "I Void Warranties"

 

Re: Version 4 bitx squealing after nextion upgrade.

_Dave_ K0MBT
 

Uniflite58
Thank you Thank you. I got the radio today. I started the repair by loading V4.3 of the standard firmware. I have been stymied in the past by kd8cec firmware. I couldn't get any audio either initially with the ubitx firmware.

The reason you could not get audio out of it was that the 8 pin audio connector on the front audio sub-board (produced by the case maker) was not making contact with the pcb. It was not fully seated when soldered One pin did not penetrate through the board and the solder did not make a connection. It fooled me for 15 minutes as it started working when I manipulated the cable.

Then reinstalled the kd8cec firmware and fit the nextion display I do hear a bit of a whine out of it. Although can make it go away with a bit of IF shift. Will try and science it out. Maybe can Juggle the BFO and take care of it. Worked some of NATANET on 40 and made several contacts tonight with it and got good audio reports several stations. One as far as 1000 miles.

Re: Low output on CW UBITX

Rod Russell-Brown
 

Thanks ill oos, Curt and Alison for your replies and thoughts. I’ll check out Alison’s ideas re filters. Hopefully I can proper power on CW and SSB.
--
Cheers,

Rod

__________________
Rod Russell-Brown
Southgate Christian Community

thanks!! re my build questions

dey <deyoung1@...>
 

Thanks to all the posts that answered my questions.  Tomorrow, I will finish wiring the 4 pin mic (to match the unused mic for another rig I have).  Then will start exploring the code – after backing it up.

That was a lesson I learned 47 years ago with a program that was on 80-column cards – all 14 trays (about 28,000 lines of code).  Back then, that was a large program.  I replaced it with something that was only about 1,400 lines of code and it ran better, faster, and all the other junk.

So, now that I am retired, I have more time to play with computers and other interests.

73’s

Derrick/W4DEY

Microphone

Bob Lunsford <nocrud222@...>
 

In a previous comment, someone said he had ideas of
using a mocrophone from a CB radio on the MBitX.

I do not remember who it was and the comment was in
a post that was addressing another question. While
this may be old news to most here, I found a circuit for
using a dynamic microphone on the MBitX and here
is the website below.

Perhaps this will be useful to someone:

http://ubitx.net/2018/12/05/dynamic-mic-preamp-runs-off-phantom-power-from-ubitx/

Re: Ubitx microphony

iz oos
 

That videos show this effect may be far more widespread than one might think. Then my question is how mobile SSB transceivers mitigate this issue. Does that white glue serve to the purpose?


Il 20/dic/2018 19:01, "Gwen Patton" <ardrhi@...> ha scritto:
Multi-layer ceramic capacitors can be microphonic due to piezoelectric effects. Dave Jones from EEVBlog has at least one video on the phenomenon. Even a simple ceramic disc cap can show microphonic activity. SMD capacitors are prone to this AND to cracking from piezoelectric shape-change and flex, so there are multi-layer SMD ceramic caps designed to minimize these effects. You can sometimes see this really badly in cheaper solid-state digital oscilloscopes. Bang on the case, or on the table it's sitting on, and a waveform can get distorted by the caps generating small currents from the vibration.

Here's a few.
https://youtu.be/F2gX-R1k7MM
https://youtu.be/wePQltAe3_4
https://youtu.be/0Iv2TnI0C98


Re: Ubitx microphony

Peter Russell <peter.russell@...>
 

I think I might have found the reason for this microphony.
It seems to be around C78 / C72, C78 being the favourite.
I don't have a smd capacitor, so I'll try a small leaded one.

I'll post when I've swapped it out.

(as one who was brought up on valves (tubes ) I hate smd's!)

Peter G8FWY


On 21/12/2018 00:16, Bob Lunsford via Groups.Io wrote:
The usual method to locate a microphonic device problem area
is to use a small stiff non-metalic brush and sweep the board in
small passes and this tends to show the general area. Then I have
used a drinking straw and tapped lightly the components in that
general area. In a way, a microphonic problem is the easy one to
fix because locating the problem does not require diagnostics of
any electronic circuits with a 'scope, etc.
Some components can be microphonic but all things considered,
I would guess it's a bad solder joint. Suspect this first. If you see
some joints with a magnifying glass that look "frosty" or granular,
touch them with the tip of a hot soldering iron AFTER turning off
the power, of course. This usually is the fix for a bad joint. Some
bad joints are hard to detect, though.
Bad solder joints are not all that uncommon. On the BitX boards,
considering that they are flow soldered, suspect the wires connected
to the board first. However, don't forget the components on the front
panel.
Please let us know what you find. This falls in the unique list of what
can be wrong with a radio.
Bob — KK5R
--------------------------------------------
On Thu, 12/20/18, Peter Russell <peter.russell@...> wrote:
Subject: Re: [BITX20] Ubitx microphony
To: BITX20@groups.io
Date: Thursday, December 20, 2018, 11:00 AM
When I say "microphony"
I mean that the circuit boards are acting as a
microphone - any slight tap on the case can be
heard loudly in the phones.
I haven't
tried it on transmit yet, so I don't know whether it
will be a
problem there also.
I'm sure I've seen reference to it
somewhere but I'm not sure where.
Any
ideas will be welcome.
Peter. G8FWY
On 20/12/2018 15:05, iz oos
wrote:
> What do you mean exactly with
'bit' of microphone? If you refer to low
> average SSB output, I replaced to add
another resistor (47ohm)in
> parallel to
R63 and worked nicely. However late November Barry Underwood

> suggested to use a VOGAD. So I have
just made (I still need to test it)
>
another external box with that compressor to use also with
other SSB
> QRPs, like ILER. I have a
mil surplus radio that use the VOGAD and I
> have always been impressed by it, as you
can just whisper and have a lot
> of
output. See the attached file made by Barry.
>
>
> Il 20/dic/2018 12:35, "Peter
Russell" <peter.russell@...

> <mailto:peter.russell@...>>
ha scritto:
>
>
Hello from a newbie!
>    I've
just completed the build of my uBITX and I have to say,
I'm
>    impressed!
>    Just one little niggle - and I'm
sure I've seen it mentioned
>
somewhere but I can't remember where - I seem to have a
bit of
>    microphony. Can anyone
point me in the right direction?
>
Thanks.
>    Peter, G8FWY.
>
>    ---
>    This email has been checked for
viruses by AVG.
>    https://www.avg.com
>

>
>
>
>
---
This email has been checked for viruses by AVG.
https://www.avg.com

Re: thanks!! re my build questions

Jack, W8TEE
 

It's amazing what a little thought can do. My son was hired by a multi-national pharma company as a programmer. Every night they would get sales reports from all over the world. Then, at 1AM, a batch file would start and synthesize the worldwide sales reports. The sales/inventory report was rarely ready for the 8AM business meeting. My son replaced the batch file using a different algorithm and cut the runtime to 42 minutes! He's now the CIO for a data mining company using Scala with big data. He's doing stuff I have no idea how it's being done. When he talks about such things now, I just sit there, nodding like I understand what he's saying, and try to look smart. I don't think I'm pulling it off...

Jack, W8TEE

On Friday, December 21, 2018, 12:08:36 AM EST, dey <deyoung1@...> wrote:


Thanks to all the posts that answered my questions.  Tomorrow, I will finish wiring the 4 pin mic (to match the unused mic for another rig I have).  Then will start exploring the code – after backing it up.

That was a lesson I learned 47 years ago with a program that was on 80-column cards – all 14 trays (about 28,000 lines of code).  Back then, that was a large program.  I replaced it with something that was only about 1,400 lines of code and it ran better, faster, and all the other junk.

So, now that I am retired, I have more time to play with computers and other interests.

73’s

Derrick/W4DEY

Re: UbitX build questions

Mark Vincett
 

Thanks for the advice. I will probably start by 'scotch taping' the eletret to a pencil to test things out and improve the form factor after it is up and running. For now I am focused on soldering things in the right places and testing each connection. 
-Mark KD2QAR

On Thu, Dec 20, 2018 at 7:53 PM Bob Lunsford via Groups.Io <nocrud222=yahoo.com@groups.io> wrote:
Just one note about using a CB microphone. They are
usually dynamic which means they are like a speaker and
would look like a short to the mic input. If you want to use
one of these experimentally, put an isolating capacitor in the
mic input line so it will not short out the line. Also, if you have
a choice, use a high impedance mic ir maybe a small
transformer to make a low impedance mic look like a high
impedance mic. All this is experimental... But the little eletret
element supplied with the radio can be substituted for the mic
element in the CB mic just as easily. Put it in a cut-out piece
of styrofoam made to fit the old mic's shell and connect the
eletred to the designated wires that connect tot the radio.

For a cable, I bought a stereo-to-stereo cable at Dollar Tree
and cut off one end and used this for the mic cable. A proper
cable was not available here so I used what was for me the
most convenient.

Plug-N-chug is the name of the game, sometimes. It's like the
old Murphy's Law: We may not have time to do it right but we
can always find time to do it over.

Bob — KK5R

--------------------------------------------
On Thu, 12/20/18, Mark Vincett <kd2qar@...> wrote:

 Subject: Re: [BITX20] UbitX build questions
 To: BITX20@groups.io
 Date: Thursday, December 20, 2018, 3:18 PM

 I had/have
 the same question and stared at images and combed the web
 quite a bit trying to figure out what to do.My
 conclusion (thus far) is that there are too may mic
 configurations out there, so it appears to have been left
 intentionally vague.I think I identified at least
 8 different variations of 4 pin mic wiring by different
 manufacturers.I am still, slowly, assembling my
 uBitx and haven't started assembling the mic yet but, I
 think you will need to study the mic and the photos to
 determine which wires in the mic match the function of the
 wires in the uBitx.In my case I found an old CB
 radio mic in a junk box in the barn that I plan to attempt
 to wire to the connector provided in the kit if I can map
 the wires into the mic to the three connections in the
 uBitx.
 This
 doesn't necessarily answer the question you have but it
 might save you some time searching for an answer that may
 not exist in this case.
 -Mark
 On Thu, Dec 20, 2018 at 2:27 PM dey <deyoung1@...>
 wrote:










 First
 of all, let me apologize for asking what will
 be (hopefully) simple questions.  This is the
 second kit radio that I have assembled and the first one
 with voice capabilities.  My other radios are all
 CW.  Which is fine for me.

 I just
 received the UbitX (v4) and the assembly kit (case and other
 parts).  This version includes a mini PCB that hold
 the three (03) jacks for the front panel as well as the mic
 and speaker connection.  I have managed to get
 everything assembled except wiring the round, 4 pin mic
 jack.

 I
 cannot tell which color wire goes to which
 pin. 
 Any suggestions?

 One of
 the reasons I purchased this radio was the ability to
 “hack” the code.  But I don’t see any
 USB (or other) port to use accessing
 the Arduino.  Any
 suggestions?

 I have
 a 47 year background in software development so playing in
 the Arduino will be fun.

 Any
 help is appreciated.

 Derrick/w4dey








 --
 ----------------------------------------------
      ^
    /   \     Mark
 Vincett
  
 /___\   KD2QAR
  /    |   \  
       |       
 ME --> GA '92 
 ----------------------------------------------









--
----------------------------------------------
     ^
   /   \     Mark Vincett
  /___\   KD2QAR
 /    |   \  
      |       
ME --> GA '92 
----------------------------------------------

Re: ubitx receive signal

Dave Space
 

Thanks for the link Woody.  I'm looking forward to betting some more amplification in this ubitx, hopefully it helps.

Ubitx - carbon mic

iz oos
 

Has anyone tried a carbon mic with the ubitx? How to wire it? The Shure 104C manual seems an interesting starting point.

Re: Ubitx microphony

Yigal Tal
 

See a possible solution:https://ubitx.net/2018/11/25/solution-to-ubitx-main-board-microphonics/