Topics

uBitx mic trouble: ptt always on #ubitx #ubitx-help

Ben Miller-Jacobson
 

Hello everyone. Something weird is going on wirh my mic and I am running out of ideas. I just wired up my mic the other day, but plugging it in makes the radio immediately go into transmit. So of course I asume I wired it wrong, go over it catefully, fail to find a problem, then redo the whole thing just in case. No luck. Poking around in a bit more detail shows that connecting the electret mic element triggers the ptt, but so does the actual ptt. Does anyone have any idea what is going on?



I've got a V-5 board running cec firmware, with several mods that ought yo be unrelated. Not that any of that likely matters.



Thanks,

Ben - KD8OKR

MVS Sarma
 

Ben,
I am sure that you had wired the key socket with 4.7k pull up. 
If not, the moment you switch on your ubitcv5, it will try to go to Tx.

Please confirm.

On Wed, 25 Sep 2019, 11:12 am Ben Miller-Jacobson, <bmillerjacobson@...> wrote:
Hello everyone. Something weird is going on wirh my mic and I am running out of ideas. I just wired up my mic the other day, but plugging it in makes the radio immediately go into transmit. So of course I asume I wired it wrong, go over it catefully, fail to find a problem, then redo the whole thing just in case. No luck. Poking around in a bit more detail shows that connecting the electret mic element triggers the ptt, but so does the actual ptt. Does anyone have any idea what is going on?



I've got a V-5 board running cec firmware, with several mods that ought yo be unrelated. Not that any of that likely matters.



Thanks,

Ben - KD8OKR

Ben Miller-Jacobson
 

Thanks for the suggestion, but that isn't the problem. The resistor is installed, and it only goes into transmit when the mic is plugged in.

On Tuesday, September 24, 2019, MVS Sarma wrote:
Ben,
I am sure that you had wired the key socket with 4.7k pull up.
If not, the moment you switch on your ubitcv5, it will try to go to Tx.

Please confirm.

On Wed, 25 Sep 2019, 11:12 am Ben Miller-Jacobson, <
bmillerjacobson@...> wrote:

Hello everyone. Something weird is going on wirh my mic and I am running
out of ideas. I just wired up my mic the other day, but plugging it in
makes the radio immediately go into transmit. So of course I asume I wired
it wrong, go over it catefully, fail to find a problem, then redo the whole
thing just in case. No luck. Poking around in a bit more detail shows that
connecting the electret mic element triggers the ptt, but so does the
actual ptt. Does anyone have any idea what is going on?



I've got a V-5 board running cec firmware, with several mods that ought yo
be unrelated. Not that any of that likely matters.



Thanks,

Ben - KD8OKR



--
Sent from my Sailfish device

MVS Sarma
 

Appears simplecwiring error. Please try fresh wiring . . Jeck pin #  confuse. 
Beetter depend on another wiring diagram availsble on bitx20 groups site. I shall try to link.

On Wed, 25 Sep 2019, 11:36 am Ben Miller-Jacobson, <bmillerjacobson@...> wrote:
Thanks for the suggestion,  but that isn't the problem. The resistor is installed, and it only goes into transmit when the mic is plugged in.

On Tuesday, September 24, 2019, MVS Sarma wrote:
> Ben,
> I am sure that you had wired the key socket with 4.7k pull up.
> If not, the moment you switch on your ubitcv5, it will try to go to Tx.
>
> Please confirm.
>
> On Wed, 25 Sep 2019, 11:12 am Ben Miller-Jacobson, <
> bmillerjacobson@...> wrote:
>
> > Hello everyone. Something weird is going on wirh my mic and I am running
> > out of ideas. I just wired up my mic the other day, but plugging it in
> > makes the radio immediately go into transmit. So of course I asume I wired
> > it wrong, go over it catefully, fail to find a problem, then redo the whole
> > thing just in case. No luck. Poking around in a bit more detail shows that
> > connecting the electret mic element triggers the ptt, but so does the
> > actual ptt. Does anyone have any idea what is going on?
> >
> >
> >
> > I've got a V-5 board running cec firmware, with several mods that ought yo
> > be unrelated. Not that any of that likely matters.
> >
> >
> >
> > Thanks,
> >
> > Ben - KD8OKR
> >
> >
>
>
>
>

--
Sent from my Sailfish device


MVS Sarma
 

hope this  pdf should help you Ben.


On Wed, Sep 25, 2019 at 12:40 PM MVS Sarma via Groups.Io <mvssarma=gmail.com@groups.io> wrote:
Appears simplecwiring error. Please try fresh wiring . . Jeck pin #  confuse. 
Beetter depend on another wiring diagram availsble on bitx20 groups site. I shall try to link.

On Wed, 25 Sep 2019, 11:36 am Ben Miller-Jacobson, <bmillerjacobson@...> wrote:
Thanks for the suggestion,  but that isn't the problem. The resistor is installed, and it only goes into transmit when the mic is plugged in.

On Tuesday, September 24, 2019, MVS Sarma wrote:
> Ben,
> I am sure that you had wired the key socket with 4.7k pull up.
> If not, the moment you switch on your ubitcv5, it will try to go to Tx.
>
> Please confirm.
>
> On Wed, 25 Sep 2019, 11:12 am Ben Miller-Jacobson, <
> bmillerjacobson@...> wrote:
>
> > Hello everyone. Something weird is going on wirh my mic and I am running
> > out of ideas. I just wired up my mic the other day, but plugging it in
> > makes the radio immediately go into transmit. So of course I asume I wired
> > it wrong, go over it catefully, fail to find a problem, then redo the whole
> > thing just in case. No luck. Poking around in a bit more detail shows that
> > connecting the electret mic element triggers the ptt, but so does the
> > actual ptt. Does anyone have any idea what is going on?
> >
> >
> >
> > I've got a V-5 board running cec firmware, with several mods that ought yo
> > be unrelated. Not that any of that likely matters.
> >
> >
> >
> > Thanks,
> >
> > Ben - KD8OKR
> >
> >
>
>
>
>

--
Sent from my Sailfish device


Werner de Vos
 

Sounds like the connector is failing.

Vic WA4THR
 

On my V4 board there was enough drop when I plugged the mic in to cause the uBitX to cycle in and out of transmit. The internal Arduino resistor was not up to holding the 5v signal above the keying threshold, which I could monitor using the KD8CEC software. I added an external 5v dropping resistor and have had no issues since.

=Vic=

V Zecchinelli
 

Did you check the micro switch to be sure it isn't always closed?

Vince


On 9/25/2019 1:42 AM, Ben Miller-Jacobson wrote:
Hello everyone. Something weird is going on wirh my mic and I am running out of ideas. I just wired up my mic the other day, but plugging it in makes the radio immediately go into transmit. So of course I asume I wired it wrong, go over it catefully, fail to find a problem, then redo the whole thing just in case. No luck. Poking around in a bit more detail shows that connecting the electret mic element triggers the ptt, but so does the actual ptt. Does anyone have any idea what is going on?



I've got a V-5 board running cec firmware, with several mods that ought yo be unrelated. Not that any of that likely matters.



Thanks,

Ben - KD8OKR

Arv Evans
 

Ben

Not all mike jacks are built the same.  A quick check might be to use your ohm meter to verify that mike jack conections are going to the proper pads on the PCB.  After verifying jack-to-board connections then apply power and use your VOM to verify that voltages are correct for each lead.  

Insert a new mike plug (no mike cable) to see if the problem might be in the jack.

If the shield connection is not grounded the PTT and mike audio will interact.  This usually happens it the jack is installed on a plastic panel and the shield connection is not connected to circuit ground.  

Might also be a wiring problem in the mike plug, cable, or in the mike itself.

You could connect only the ground and mice audio, leaving the PTT unconnected to check if the problem involves the audio path or the PTT circuit.

Arv
_-_



On Tue, Sep 24, 2019, 11:42 PM Ben Miller-Jacobson <bmillerjacobson@...> wrote:
Hello everyone. Something weird is going on wirh my mic and I am running out of ideas. I just wired up my mic the other day, but plugging it in makes the radio immediately go into transmit. So of course I asume I wired it wrong, go over it catefully, fail to find a problem, then redo the whole thing just in case. No luck. Poking around in a bit more detail shows that connecting the electret mic element triggers the ptt, but so does the actual ptt. Does anyone have any idea what is going on?



I've got a V-5 board running cec firmware, with several mods that ought yo be unrelated. Not that any of that likely matters.



Thanks,

Ben - KD8OKR

Ben Miller-Jacobson
 

Thanks for the suggestions, everyone.

Vic, your issue sounds the most like mine of the things I haven't at least tenatively rulled out. I notice that I am confused, though. If the resistor wasn't adequate, shouldn't it go into ptt even without the mic like it would without the one for the key socket?

On Wednesday, September 25, 2019, Vic WA4THR via Groups.Io wrote:
On my V4 board there was enough drop when I plugged the mic in to cause the uBitX to cycle in and out of transmit. The internal Arduino resistor was not up to holding the 5v signal above the keying threshold, which I could monitor using the KD8CEC software. I added an external 5v dropping resistor and have had no issues since.

=Vic=



--
Sent from my Sailfish device

_Dave_ K0MBT
 

I bought one used and had similar trouble. Turns out that the pull up resistor used in it was 470Ὡ. I doubt if it was the resistor put in by the manufacturer, I think the original assembler may have used the 3 significant digit code instead of the current 4 significant digit code

Maybe not politically correct but this is how I have remembered the resistor code for past 50 years.
B(ad ) black 0
B(oys) brown 1
R(ape) red 2
O(ur) orange 3
Y(oung) yellow 4 
G(irls) green 5
B(ut) blue 6 
V(iolet) violet 7
G(ives) grey 8 
W(illingly) 9
--
73
Dave
k0mbt
Ham_Made_Keys

Ben Miller-Jacobson
 

Vic, I seem to have found an old set of posts by you where you talked about your issue and fix. Did you end up disconnecting the built in pull up resistor? The value you quoted makes me think you added to it rather than replaced it.

On Wednesday, September 25, 2019, Vic WA4THR via Groups.Io wrote:
On my V4 board there was enough drop when I plugged the mic in to cause the uBitX to cycle in and out of transmit. The internal Arduino resistor was not up to holding the 5v signal above the keying threshold, which I could monitor using the KD8CEC software. I added an external 5v dropping resistor and have had no issues since.

=Vic=



--
Sent from my Sailfish device

Ben Miller-Jacobson
 

Update: adding a 4.7k resister between the ptt pin and the 5v pin solced the problem for me.

On Wednesday, September 25, 2019, Ben Miller-Jacobson via Groups.Io wrote:
Vic, I seem to have found an old set of posts by you where you talked about your issue and fix. Did you end up disconnecting the built in pull up resistor? The value you quoted makes me think you added to it rather than replaced it.

On Wednesday, September 25, 2019, Vic WA4THR via Groups.Io wrote:
On my V4 board there was enough drop when I plugged the mic in to cause the uBitX to cycle in and out of transmit. The internal Arduino resistor was not up to holding the 5v signal above the keying threshold, which I could monitor using the KD8CEC software. I added an external 5v dropping resistor and have had no issues since.

=Vic=



--
Sent from my Sailfish device


--
Sent from my Sailfish device

Ben Miller-Jacobson
 

I'm not really faulting you for using a mnemonic that was a product of the times, but this is a case where litterally anything else would be just as good and "not politically correct" ends up meaning something more like "makes the hobby just that little bit less inclusive, for no benefit in particular". Wikipedia offers a whole page of alternatives.

https://en.m.wikipedia.org/wiki/List_of_electronic_color_code_mnemonics

On Wednesday, September 25, 2019, _Dave_ K0MBT wrote:
I bought one used and had similar trouble. Turns out that the pull up resistor used in it was 470Ὡ. I doubt if it was the resistor put in by the manufacturer, I think the original assembler may have used the 3 significant digit code instead of the current 4 significant digit code

Maybe not politically correct but this is how I have remembered the resistor code for past 50 years.
B(ad ) black 0
B(oys) brown 1
R(ape) red 2
O(ur) orange 3
Y(oung) yellow 4
G(irls) green 5
B(ut) blue 6
V(iolet) violet 7
G(ives) grey 8
W(illingly) 9
--
73
Dave
k0mbt
Ham_Made_Keys ( http://veloliner.com/ham/k0mbtkey.pdf )



--
Sent from my Sailfish device

Donald <donwestpwl@...>
 

Personally, I don't use wikipedia. Seems to be a blog where anyone can post anything. There is no author listed for the resistor color code mnemonic page.

Hmm, that's interesting: Thunderbird email program doesn't know the word "wikipedia". It thinks I have misspelled something. --Donald, KB5PWL

On 9/25/2019 4:25 PM, Ben Miller-Jacobson wrote:
... Wikipedia offers a whole page of alternatives.
https://en.m.wikipedia.org/wiki/List_of_electronic_color_code_mnemonics

Christopher Miller
 

Actually, its moderated by the community and citations are required. Peer review is encouraged, and if issues arise they are solved. Just because it is open source doesn’t make it unreliable.

Besides they are alternate pneumonics, not exactly scholarly material. 

On Wed, Sep 25, 2019 at 8:03 PM Donald <donwestpwl@...> wrote:
Personally, I don't use wikipedia. Seems to be a blog where anyone can
post anything. There is no author listed for the resistor color code
mnemonic page.

Hmm, that's interesting: Thunderbird email program doesn't know the word
"wikipedia". It thinks I have misspelled something. --Donald, KB5PWL

On 9/25/2019 4:25 PM, Ben Miller-Jacobson wrote:
> ... Wikipedia offers a whole page of alternatives.
> https://en.m.wikipedia.org/wiki/List_of_electronic_color_code_mnemonics
>



Vic WA4THR
 

If you have a voltmeter, monitor the PTT line before you plug in the mic and after, and when you press the PTT switch That will show whether the line needs an external pull-up circuit. In my case, there was a little bit of a load when the mic was plugged in and that dropped the voltage with only the internal pull-up resistor enough to be right on the threshold of detecting a PTT signal, so I just added an external resistor from 5v to the PTT line and that kept the voltage up when not keying. Another solution is to go into the software sketch and change the voltage level at which it detects the PTT switch. This is a bit unique to the uBitX, since it detects the signal in the Arduino. The BitX40, where I use the same microphone, just keys a relay when the switch is pressed.

=Vic=

Vic WA4THR
 

I just added the external pull up resistor to 5v without any other changes. It has worked fine ever since.

=Vic=

Vic WA4THR
 

I( guess I should have read all the posts you made before replying! Great that the external pull-up resistor worked, that was what I needed, too.

=Vic=

STEVE
 

What is the volume control pot value? The one that came with it is 100k ohms,the video showed 100 ohms. The schematic doesn’t specify. 

Steve Behlmer

On Sep 25, 2019, at 12:33 AM, MVS Sarma <mvssarma@...> wrote:


hope this  pdf should help you Ben.


On Wed, Sep 25, 2019 at 12:40 PM MVS Sarma via Groups.Io <mvssarma=gmail.com@groups.io> wrote:
Appears simplecwiring error. Please try fresh wiring . . Jeck pin #  confuse. 
Beetter depend on another wiring diagram availsble on bitx20 groups site. I shall try to link.

On Wed, 25 Sep 2019, 11:36 am Ben Miller-Jacobson, <bmillerjacobson@...> wrote:
Thanks for the suggestion,  but that isn't the problem. The resistor is installed, and it only goes into transmit when the mic is plugged in.

On Tuesday, September 24, 2019, MVS Sarma wrote:
> Ben,
> I am sure that you had wired the key socket with 4.7k pull up.
> If not, the moment you switch on your ubitcv5, it will try to go to Tx.
>
> Please confirm.
>
> On Wed, 25 Sep 2019, 11:12 am Ben Miller-Jacobson, <
> bmillerjacobson@...> wrote:
>
> > Hello everyone. Something weird is going on wirh my mic and I am running
> > out of ideas. I just wired up my mic the other day, but plugging it in
> > makes the radio immediately go into transmit. So of course I asume I wired
> > it wrong, go over it catefully, fail to find a problem, then redo the whole
> > thing just in case. No luck. Poking around in a bit more detail shows that
> > connecting the electret mic element triggers the ptt, but so does the
> > actual ptt. Does anyone have any idea what is going on?
> >
> >
> >
> > I've got a V-5 board running cec firmware, with several mods that ought yo
> > be unrelated. Not that any of that likely matters.
> >
> >
> >
> > Thanks,
> >
> > Ben - KD8OKR
> >
> >
>
>
>
>

--
Sent from my Sailfish device


<uBITX_wireup V1.8.pdf>