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RE50B microphone connected to K3

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John Kountz

RE50B microphone connected to K3

Has anyone had experience in tying pin 3 to pin one in an XLR connector to
enable the transition from a balanced microphone to the unbalanced input of
the K3? In this regard I have used this arrangement to attach an
Electrovoice RE50B to my K3 and, although I have made satisfactory
contactswith this arrangement, I ask because many of you respondents appear
experienced in audio and may have alternatives to making this
interconnection.
John Kountz, WO1S/T6EE
2 x K3s

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ve3dvy

Re: RE50B microphone connected to K3

RE50b is a low z dynamic mic that is well suited to voice and is an
excellent mic should work well for K3. To use this unbalanced you
are correct to connect pin1 to pin3 (cold to ground) do not
connect the XLR connector body to the ground it should be left
floating. I have used many balanced dynamics in this way with many
rigs without issue
.

David Moes
VE3DVY

www.Facebook.com/PTBOTheatreGuild
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>
> --- Original message ---
> Subject: [Elecraft] RE50B microphone connected to K3
> From: John Kountz <[hidden email]>
> To: <[hidden email]>
> Date: Saturday, 04/02/2012 11:12 AM
>
> Has anyone had experience in tying pin 3 to pin one in an XLR
> connector to
> enable the transition from a balanced microphone to the unbalanced
> input of
> the K3? In this regard I have used this arrangement to attach an
> Electrovoice RE50B to my K3 and, although I have made satisfactory
> contactswith this arrangement, I ask because many of you respondents
> appear
> experienced in audio and may have alternatives to making this
> interconnection.
> John Kountz, WO1S/T6EE
> 2 x K3s
>
> ______________________________________________________________
> 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

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Jim Brown-10

Re: RE50B microphone connected to K3

On 2/4/2012 8:42 AM, David Moes wrote:
> E50b is a low z dynamic mic that is well suited to voice and is an
> excellent mic should work well for K3.

Yes. An RE11 or RE16 is even better, because they are directional and
reduce background noise pickup (fans, room noise, etc.)

> To use this unbalanced you
> are correct to connect pin1 to pin3 (cold to ground)

Yes, Pin 3 to Pin 1 is right, but Pin 1 is the SHIELD, not "ground,"
and Pin One must go to the SHIELDING ENCLOSURE (the chassis) to provide
shielding and prevent "the Pin One Problem." The distinction between
"ground" which some interpret (wrongly) as a connection to the EARTH,
and a connection to the SHIELDING ENCLOSURE is important -- no
connection to the EARTH is needed to prevent noise or RFI issues.

> do not connect the XLR connector body to the ground it should be left floating.

Again, this word "ground" confuses the issue. Inside the microphone,
there MUST be a connection between Pin One and the metal shell of the
mic -- this provides shielding for the mic itself. AES Standards also
call for a connection between Pine One and the shielding enclosure
INSIDE EQUIPMENT, but require that there be NO connection between the
cable shield and the cable shell. There are very important reasons for
this that don't matter here. :)

73, Jim Brown K9YC

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Joe Subich, W4TV-4

Re: RE50B microphone connected to K3

In reply to this post by John Kountz

You want to keep pin one separate ...

Connect pin 3 to the "microphone return" in the transceiver
(pin 7 in Elecraft/Kenwood transceivers)
Connect pin 1 to the chassis - the *SHELL* of the Foster mic plug
in most transceiver.

If you do it right, you will use shielded twisted pair cable -
the twisted pair will provide a high degree of hum/RF rejection
and the shield will be the icing on the cake as K9YC likes to
point out.

Even though the transceiver mic inputs are not truly balanced,
treating them as pseudo-balanced inputs with twisted pair cable
and an isolated shield goes a long way to keeping things clean.

Manufacturers like Icom and Yaesu that use a coaxial lead (shield
is the return) for their microphone and then float the mic return
across the emitter resistor in the mic preamp or an RF choke are
asking for RFI and hum problems. When some third parties then
recommend connecting the mic return to the shell of the Foster
mic plug with the cut-off component lead they compound the problems
by upsetting the bias of the mic preamp!

73,

... Joe, W4TV

On 2/4/2012 11:12 AM, John Kountz wrote:

> Has anyone had experience in tying pin 3 to pin one in an XLR connector to
> enable the transition from a balanced microphone to the unbalanced input of
> the K3? In this regard I have used this arrangement to attach an
> Electrovoice RE50B to my K3 and, although I have made satisfactory
> contactswith this arrangement, I ask because many of you respondents appear
> experienced in audio and may have alternatives to making this
> interconnection.
> John Kountz, WO1S/T6EE
> 2 x K3s
>
> ______________________________________________________________
> 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
>

ve3dvy

Re: RE50B microphone connected to K3

In reply to this post by John Kountz

I guess I misused the term ground. vs shield. I think we are
basically saying the same thing just that you are using correct
terminology, My Bad.

David Moes
VE3DVY

www.Facebook.com/PTBOTheatreGuild
www.Twitter.com/PTBOTheatre
www.YouTube.com/PTBOTheatreGuild

>
> --- Original message ---
> Subject: Re: [Elecraft] RE50B microphone connected to K3
> From: Jim Brown <[hidden email]>
> To: <[hidden email]>
> Date: Saturday, 04/02/2012 9:29 AM
>
> On 2/4/2012 8:42 AM, David Moes wrote:
>>
>> E50b is a low z dynamic mic that is well suited to voice and is an
>> excellent mic should work well for K3.
>
> Yes. An RE11 or RE16 is even better, because they are directional and
> reduce background noise pickup (fans, room noise, etc.)
>
>>
>> To use this unbalanced you
>> are correct to connect pin1 to pin3 (cold to ground)
>
> Yes, Pin 3 to Pin 1 is right, but Pin 1 is the SHIELD, not "ground,"
> and Pin One must go to the SHIELDING ENCLOSURE (the chassis) to
> provide
> shielding and prevent "the Pin One Problem." The distinction between
> "ground" which some interpret (wrongly) as a connection to the EARTH,
> and a connection to the SHIELDING ENCLOSURE is important -- no
> connection to the EARTH is needed to prevent noise or RFI issues.
>
>>
>> do not connect the XLR connector body to the ground it should be left
>> floating.
>
> Again, this word "ground" confuses the issue. Inside the microphone,
> there MUST be a connection between Pin One and the metal shell of the
> mic -- this provides shielding for the mic itself. AES Standards also
> call for a connection between Pine One and the shielding enclosure
> INSIDE EQUIPMENT, but require that there be NO connection between the
> cable shield and the cable shell. There are very important reasons
> for
> this that don't matter here. :)
>
> 73, Jim Brown K9YC
>
>
>
> ______________________________________________________________
> 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