Elecraft › [K3]

K3, CM-500 oddity, a follow up

Classic

List

Threaded

7 messages Options

Richard Fjeld

K3, CM-500 oddity, a follow up

For the benefit to others like myself, this is a follow-up to the post below.

I have been re-using an adapter made for another radio&headset-mic with my CM-500 mic. What I didn't know is that there was a 22k resistor in the adapter that bridged the 8V to the tip and ring which were wired common.

I have to admit to being ignorant of how the bias worked. I had thought the 8V on pin 6 would be controlled by the menu option. Everything was fine until I wanted to try using a Dynamic mic with the same lashup.

As for the CM-500, I'd like to know if it is the tip, or ring, on the 1/8 inch plug that is the actual mic audio lead. I will have to try one, or the other, to see. If anyone else has done this, please let me know. It would be nice if mic plugs were standardized. Maybe the new ones are, but I don't know what it is.

Thanks,
Dick, n0ce

I bought a CM-500 less than a year ago. A few days ago, I was trying things, and I turned off the bias, and the mic still works as if, no change. I tried testing without tearing things apart, and I think the bias is still on.

73,

Richard Fjeld, n0ce

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Joe Subich, W4TV-4

Re: [Elecraft_K3] K3, CM-500 oddity, a follow up

> As for the CM-500, I'd like to know if it is the tip, or ring, on the
> 1/8 inch plug that is the actual mic audio lead. I will have to try
> one, or the other, to see.

The answer is quite simple ... the tip and ring of the CM-500 mic plug
are connected together.

The supplied battery box has no connection to the ring of the mic
(3.5mm jack). Tip of the jack is connected to tip and ring of the
3.5mm plug via a 1 uF capacitor. The positive side of the battery
(+3.0V) is connected to the tip of the 3.5mm jack with a 2.2K Ohm
resistor. The negative side of the battery is connected to sleeve
(common/ground) of both plug and jack (input/output).

73,

... Joe, W4TV

On 3/8/2012 3:16 PM, Richard Fjeld wrote:

> For the benefit to others like myself, this is a follow-up to the post below.
>
> I have been re-using an adapter made for another radio&headset-mic with my CM-500 mic. What I didn't know is that there was a 22k resistor in the adapter that bridged the 8V to the tip and ring which were wired common.
>
> I have to admit to being ignorant of how the bias worked. I had thought the 8V on pin 6 would be controlled by the menu option. Everything was fine until I wanted to try using a Dynamic mic with the same lashup.
>
> As for the CM-500, I'd like to know if it is the tip, or ring, on the 1/8 inch plug that is the actual mic audio lead. I will have to try one, or the other, to see. If anyone else has done this, please let me know. It would be nice if mic plugs were standardized. Maybe the new ones are, but I don't know what it is.
>
> Thanks,
> Dick, n0ce
>
>
>
> I bought a CM-500 less than a year ago. A few days ago, I was trying things, and I turned off the bias, and the mic still works as if, no change. I tried testing without tearing things apart, and I think the bias is still on.
>
>
>
> 73,
>
> Richard Fjeld, n0ce
>
>
>

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Mike Reublin

Re: K3, CM-500 oddity, a follow up

In reply to this post by Richard Fjeld

Dick -

Avoid all the adapter cruft and plug the headset into the rear panel. Nothing hanging
off the front panel to snag stuff. Set Menu|Mic Sel to rP.h, and turn the bias on.

73, Mike NF4L

On 3/8/2012 3:16 PM, Richard Fjeld wrote:

Don Wilhelm-4

Re: [Elecraft_K3] K3, CM-500 oddity, a follow up

In reply to this post by Joe Subich, W4TV-4

For those who do not understand the technicalities, I would suggest that
the CM-500 cannot be plugged directly into the KX3 jack. The KX3 PTT is
on the ring connection, and the stock CM-500 connects the Tip and ring
together for the AF connection.

It MAY work, but it is not a certainty, the KX3 function of the ring
contact is three-fold - PTT, UP and DWN.
the audio level on the ring may or may not induce one of those functions
depending on the voltage and current.

It would be better to create a homebrew adapter that would accept the
CM-500 AF on the tip and ring, and connect that only to the tip of the
KX3 jack, and at the same time add a small box with a pushbutton for PTT
and also pushbuttons (with the appropriate resistors) for UP and DWN).

In other words, the stock CM-500 *may* work, but it may not depending on
the levels presented at the ring connection.

This situation may also be present in microphone designed primarily for
computer use - they may be OK, but if they create funny PTT or UP or DWN
conditions, blame it on the connection between tip and ring on the
microphone jack.

73,
Don W3FPR

On 3/8/2012 3:46 PM, Joe Subich, W4TV wrote:

>> As for the CM-500, I'd like to know if it is the tip, or ring, on the
>> 1/8 inch plug that is the actual mic audio lead. I will have to try
>> one, or the other, to see.
> The answer is quite simple ... the tip and ring of the CM-500 mic plug
> are connected together.
>
> The supplied battery box has no connection to the ring of the mic
> (3.5mm jack). Tip of the jack is connected to tip and ring of the
> 3.5mm plug via a 1 uF capacitor. The positive side of the battery
> (+3.0V) is connected to the tip of the 3.5mm jack with a 2.2K Ohm
> resistor. The negative side of the battery is connected to sleeve
> (common/ground) of both plug and jack (input/output).
>
> 73,
>
> ... Joe, W4TV
>
>

gdaught6

Re: K3, CM-500 oddity, a follow up

In reply to this post by Mike Reublin

Mike wrote...

> Avoid all the adapter cruft and plug the headset into the rear panel. Nothing hanging
> off the front panel to snag stuff. Set Menu|Mic Sel to rP.h, and turn the bias on.

For the CM-500, you'd better set it to rP.l because the CM-500 is a hot microphone!

73,

George T Daughters, K6GT
CU in the California QSO Party (CQP)
October 6-7, 2012

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Eugene Balinski

Re: [Elecraft_K3] K3, CM-500 oddity, a follow up

In reply to this post by Don Wilhelm-4

I am sure that someone has mentioned this before however,
has someone located a good source of matching plugs for the
mic and headphone jack on the KX3? I would like to order
some in advance and start some projects.

73

Gene K1NR
KX3 S/N TBD : -)

On Thu, 08 Mar 2012 21:15:06 -0500
Don Wilhelm <[hidden email]> wrote:

> For those who do not understand the technicalities, I
> would suggest that
> the CM-500 cannot be plugged directly into the KX3 jack.
> The KX3 PTT is
> on the ring connection, and the stock CM-500 connects the
> Tip and ring
> together for the AF connection.
>
> It MAY work, but it is not a certainty, the KX3 function
> of the ring
> contact is three-fold - PTT, UP and DWN.
> the audio level on the ring may or may not induce one of
> those functions
> depending on the voltage and current.
>
> It would be better to create a homebrew adapter that
> would accept the
> CM-500 AF on the tip and ring, and connect that only to
> the tip of the
> KX3 jack, and at the same time add a small box with a
> pushbutton for PTT
> and also pushbuttons (with the appropriate resistors) for
> UP and DWN).
>
> In other words, the stock CM-500 *may* work, but it may
> not depending on
> the levels presented at the ring connection.
>
> This situation may also be present in microphone designed
> primarily for
> computer use - they may be OK, but if they create funny
> PTT or UP or DWN
> conditions, blame it on the connection between tip and
> ring on the
> microphone jack.
>
> 73,
> Don W3FPR
>
> On 3/8/2012 3:46 PM, Joe Subich, W4TV wrote:
> >> As for the CM-500, I'd like to know if it is the tip,
> or ring, on the
> >> 1/8 inch plug that is the actual mic audio lead. I
> will have to try
> >> one, or the other, to see.
> > The answer is quite simple ... the tip and ring of the
> CM-500 mic plug
> > are connected together.
> >
> > The supplied battery box has no connection to the ring
> of the mic
> > (3.5mm jack). Tip of the jack is connected to tip and
> ring of the
> > 3.5mm plug via a 1 uF capacitor. The positive side of
> the battery
> > (+3.0V) is connected to the tip of the 3.5mm jack with
> a 2.2K Ohm
> > resistor. The negative side of the battery is
> connected to sleeve
> > (common/ground) of both plug and jack (input/output).
> >
> > 73,
> >
> > ... Joe, W4TV
> >
> >
>

______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list:
> http://www.qsl.net/donate.html

---------------------------------------------------------------------
Web mail provided by NuNet, Inc. The Premier National provider.
http://www.nni.com/
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Don Wilhelm-4

Re: [Elecraft_K3] K3, CM-500 oddity, a follow up

Greg posted these two links on 03/04/12. Other than that they are right
angle plugs, I know nothing about them.

http://www.pchcables.com/hogmrian2mas.html

http://www.pchcables.com/3foan2stmato.html

73,
Don W3FPR

On 3/9/2012 10:30 AM, Eugene Balinski wrote:

> I am sure that someone has mentioned this before however,
> has someone located a good source of matching plugs for the
> mic and headphone jack on the KX3? I would like to order
> some in advance and start some projects.
>
> 73
>
> Gene K1NR
> KX3 S/N TBD : -)
>
>
>
>
>
> On Thu, 08 Mar 2012 21:15:06 -0500
> Don Wilhelm<[hidden email]> wrote:
>> For those who do not understand the technicalities, I
>> would suggest that
>> the CM-500 cannot be plugged directly into the KX3 jack.
>> The KX3 PTT is
>> on the ring connection, and the stock CM-500 connects the
>> Tip and ring
>> together for the AF connection.
>>
>> It MAY work, but it is not a certainty, the KX3 function
>> of the ring
>> contact is three-fold - PTT, UP and DWN.
>> the audio level on the ring may or may not induce one of
>> those functions
>> depending on the voltage and current.
>>
>> It would be better to create a homebrew adapter that
>> would accept the
>> CM-500 AF on the tip and ring, and connect that only to
>> the tip of the
>> KX3 jack, and at the same time add a small box with a
>> pushbutton for PTT
>> and also pushbuttons (with the appropriate resistors) for
>> UP and DWN).
>>
>> In other words, the stock CM-500 *may* work, but it may
>> not depending on
>> the levels presented at the ring connection.
>>
>> This situation may also be present in microphone designed
>> primarily for
>> computer use - they may be OK, but if they create funny
>> PTT or UP or DWN
>> conditions, blame it on the connection between tip and
>> ring on the
>> microphone jack.
>>
>> 73,
>> Don W3FPR
>>
>> On 3/8/2012 3:46 PM, Joe Subich, W4TV wrote:
>>>> As for the CM-500, I'd like to know if it is the tip,
>> or ring, on the
>>>> 1/8 inch plug that is the actual mic audio lead. I
>> will have to try
>>>> one, or the other, to see.
>>> The answer is quite simple ... the tip and ring of the
>> CM-500 mic plug
>>> are connected together.
>>>
>>> The supplied battery box has no connection to the ring
>> of the mic
>>> (3.5mm jack). Tip of the jack is connected to tip and
>> ring of the
>>> 3.5mm plug via a 1 uF capacitor. The positive side of
>> the battery
>>> (+3.0V) is connected to the tip of the 3.5mm jack with
>> a 2.2K Ohm
>>> resistor. The negative side of the battery is
>> connected to sleeve
>>> (common/ground) of both plug and jack (input/output).
>>>
>>> 73,
>>>
>>> ... Joe, W4TV
>>>
>>>
> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list:
>> http://www.qsl.net/donate.html
> ---------------------------------------------------------------------
> Web mail provided by NuNet, Inc. The Premier National provider.
> http://www.nni.com/
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>