Elecraft

Mics for the K-3

Classic

List

Threaded

9 messages Options

Mike Kasrich

Mics for the K-3

A quick question for whoever. I saw mention that the K-3 was essentially wired like a Kenwood. I already own a Heil headset. Do I just need a new adapter set up for Kenwood and plug in or do you need to order a headset/mic from Elecraft?

Mike/aj9c
_______________________________________________
Elecraft mailing list
Post to: [hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com

Vic K2VCO

Re: Mics for the K-3

[hidden email] wrote:
> A quick question for whoever. I saw mention that the K-3 was
> essentially wired like a Kenwood. I already own a Heil headset. Do
> I just need a new adapter set up for Kenwood and plug in or do you
> need to order a headset/mic from Elecraft?

The Heil Proset that I have has two 3.5 mm phone plugs on it that go to
the adapters. They plug directly into the back panel mic and phones
jacks of the K3, so you don't need *any* adapter and you don't need to
have cords hanging off the front of your K3.

If you want to plug it into the front panel, you can use the Heil
Kenwood adapter. You do not need to buy the Elecraft version, although
that (obviously) works too!
--
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco
_______________________________________________
Elecraft mailing list
Post to: [hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com

Andrew Faber

Re: Mics for the K-3

In reply to this post by Mike Kasrich

Mike,
A Heil Kenwood adaptor works fine. I've used it. You can also simply
plug both the mic and the phones connectors from a Pro-Set into the back of
the K3 and not use the front panel inputs at all. This is really helpful in
reducing clutter in front of the radio.
73, andy, ae6y
----- Original Message -----
From: <[hidden email]>
Cc: "elecraft" <[hidden email]>
Sent: Thursday, December 13, 2007 10:12 AM
Subject: [Elecraft] Mics for the K-3

>A quick question for whoever. I saw mention that the K-3 was essentially
>wired like a Kenwood. I already own a Heil headset. Do I just need a new
>adapter set up for Kenwood and plug in or do you need to order a
>headset/mic from Elecraft?
>
> Mike/aj9c
> _______________________________________________
> Elecraft mailing list
> Post to: [hidden email]
> You must be a subscriber to post to the list.
> Subscriber Info (Addr. Change, sub, unsub etc.):
> http://mailman.qth.net/mailman/listinfo/elecraft
>
> Help: http://mailman.qth.net/subscribers.htm
> Elecraft web page: http://www.elecraft.com
>

_______________________________________________
Elecraft mailing list
Post to: [hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com

Buck - k4ia

Re: Mics for the K-3

In reply to this post by Mike Kasrich

You can get the Kenwood cables for the Heil mics and they will work
(according to Chip @ Heil). I bought one yesterday but have not yet installed it.

HOWEVER, you must be sure to turn the bias OFF in the mic selection menu of
the K3 if you are going to use a non-Elecraft mic. The MH2 from Elecraft
uses the Heil Icom element and needs bias. The other Heil mics do not use that
element and bias voltage will damage them.

k4ia
Craig "Buck"
Fredericksburg, Virginia
K3 #101

**************************************See AOL's top rated recipes
(http://food.aol.com/top-rated-recipes?NCID=aoltop00030000000004)
_______________________________________________
Elecraft mailing list
Post to: [hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com

w7aqk

Re: Mics for the K-3

Hi All,

Actually, it is more complicated than that. First of all, you need to be
sure you know exactly what kind of mike you have, as in electret or dynamic.
Also, when referring to the "Pro-Set", you should be sure to distinguish
between the Heil Pro-Set" with the HC4 or HC5 cartridges (no bias on those),
and the Elecraft Pro-Set K2 (made by Heil, and it is the "IC" version) which
does require bias.

There is some confusion about Heil microphone/headsets like the Heil
Traveler. That is also an electret, and should have bias. however, the
adapter for that microphone to mate with a Kenwood, has a dropping resistor
of some kind (I measured 2.2K ohms) between pin 5 and pin 1, which is how
you get bias I guess on a Kenwood radio--using pin 5. But the Elecraft K3
is shown as having 8 v. on pin 6, not pin 5. There is, however, something
like 2.8 volts showing on pin 5 of the K3 microphone connector (front
panel). I had some email exchanges with Don Wilhelm about using this mike
(the Traveler), and he was concerned about how it seemed to be wired (via
the "Kenwood" adapter). Accordingly, I am not using it, and am using an
Elecraft Pro Set K2. I don't plan to use the Traveler until the confusion
about the Traveler clears up. I may be wrong, but it seems to me that you
don't need any connection on pin 5 or pin 6 (on the microphone) since the
bias is apparently applied to pin 1 by turning on bias with the menu. So,
maybe for Kenwood adapters, like the one the Traveler uses, one should maybe
eliminate the pin 5 to pin 1 interconnection. Alternatively, maybe you
should just make up your own adapter. Perhaps someone else can shed some
light on this.

Dave W7AQK

----- Original Message -----
From: <[hidden email]>
To: <[hidden email]>
Cc: <[hidden email]>
Sent: Thursday, December 13, 2007 11:56 AM
Subject: Re: [Elecraft] Mics for the K-3

> You can get the Kenwood cables for the Heil mics and they will work
> (according to Chip @ Heil). I bought one yesterday but have not yet
> installed it.
>
> HOWEVER, you must be sure to turn the bias OFF in the mic selection menu
> of
> the K3 if you are going to use a non-Elecraft mic. The MH2 from Elecraft
> uses the Heil Icom element and needs bias. The other Heil mics do not
> use that
> element and bias voltage will damage them.
>
> k4ia
> Craig "Buck"
> Fredericksburg, Virginia
> K3 #101
>
>
>
>
> **************************************See AOL's top rated recipes
> (http://food.aol.com/top-rated-recipes?NCID=aoltop00030000000004)
> _______________________________________________
> Elecraft mailing list
> Post to: [hidden email]
> You must be a subscriber to post to the list.
> Subscriber Info (Addr. Change, sub, unsub etc.):
> http://mailman.qth.net/mailman/listinfo/elecraft
>
> Help: http://mailman.qth.net/subscribers.htm
> Elecraft web page: http://www.elecraft.com

Joe Subich, W4TV

RE: Mics for the K-3

There are two means of supplying bias for an electret (or preamplified)
microphone. The first, used by Elecraft in the K3 and by Icom, is to
simply add DC voltage to the microphone "hot" lead. The second, used
by the rest of the world is to use a "power adder" circuit to the mic
line and supply the bias externally.

The power adder consists of a capacitor between the mic element and the
microphone input of the radio (to prevent the bias from upsetting the
microphone amplifier) and a resistor connected to the junction of the
mic element and the capacitor. Power is applied to the other end of
the resistor from any available source which can be another pin on
the mic connector (pin 6 for Kenwood, pin 5 for Elecraft, pin 2 for
Yaesu/TenTec/Flex-radio) or even a battery. The resistor is not there
for voltage dropping, it is there to limit the current to the mic
element to a safe value and to prevent the internal impedance of the
power supply, particularly any filter or bypass capacitor, from
loading the mic (shunting the output).

> There is some confusion about Heil microphone/headsets like the Heil
> Traveler. That is also an electret, and should have bias.

Two solutions:
1) make up your own adapter that has no blocking capacitor and no
resistor. Turn on the "pin 1" bias in the K3.
2) Use a Kenwood HSTA but move the resistor on pin 6 to pin 5.

73,

... Joe, W4TV

> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of David Yarnes
> Sent: Thursday, December 13, 2007 6:04 PM
> To: [hidden email]; [hidden email]
> Cc: [hidden email]
> Subject: Re: [Elecraft] Mics for the K-3
>
>
> Hi All,
>
> Actually, it is more complicated than that. First of all,
> you need to be
> sure you know exactly what kind of mike you have, as in
> electret or dynamic.
> Also, when referring to the "Pro-Set", you should be sure to
> distinguish
> between the Heil Pro-Set" with the HC4 or HC5 cartridges (no
> bias on those),
> and the Elecraft Pro-Set K2 (made by Heil, and it is the "IC"
> version) which
> does require bias.
>
> There is some confusion about Heil microphone/headsets like the Heil
> Traveler. That is also an electret, and should have bias.
> however, the
> adapter for that microphone to mate with a Kenwood, has a
> dropping resistor
> of some kind (I measured 2.2K ohms) between pin 5 and pin 1,
> which is how
> you get bias I guess on a Kenwood radio--using pin 5. But
> the Elecraft K3
> is shown as having 8 v. on pin 6, not pin 5. There is,
> however, something
> like 2.8 volts showing on pin 5 of the K3 microphone connector (front
> panel). I had some email exchanges with Don Wilhelm about
> using this mike
> (the Traveler), and he was concerned about how it seemed to
> be wired (via
> the "Kenwood" adapter). Accordingly, I am not using it, and
> am using an
> Elecraft Pro Set K2. I don't plan to use the Traveler until
> the confusion
> about the Traveler clears up. I may be wrong, but it seems
> to me that you
> don't need any connection on pin 5 or pin 6 (on the
> microphone) since the
> bias is apparently applied to pin 1 by turning on bias with
> the menu. So,
> maybe for Kenwood adapters, like the one the Traveler uses,
> one should maybe
> eliminate the pin 5 to pin 1 interconnection. Alternatively,
> maybe you
> should just make up your own adapter. Perhaps someone else
> can shed some
> light on this.
>
> Dave W7AQK
>

Mike Kasrich

Mics for the K-3

So what everyone is saying is we have Kenwood wiring with the need of
the Icom element. I have a mini pro , pro light whatever they called
it. (dont think it is made anymore) and have had Yaesu radios.
Everything has been plug and play up to this point. Ill have to sort
through what I have to turn on or off I guess when the rig gets here.

aj9c

_______________________________________________
Elecraft mailing list
Post to: [hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com

Vic K2VCO

Re: Mics for the K-3

Mike Kasrich wrote:
> So what everyone is saying is we have Kenwood wiring with the need of
> the Icom element.

You don't *need* the Icom element. Dynamic mics work fine as well as
Electrets. You may or may not have to change the wiring in your mic plug
depending on the way it is set up now.
--
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco
K3 no. 00007
_______________________________________________
Elecraft mailing list
Post to: [hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com

David Woolley (E.L)

Re: RE: Mics for the K-3

In reply to this post by Joe Subich, W4TV

Joe Subich, W4TV wrote:
> There are two means of supplying bias for an electret (or preamplified)
> microphone. The first, used by Elecraft in the K3 and by Icom, is to
> simply add DC voltage to the microphone "hot" lead. The second, used
> by the rest of the world is to use a "power adder" circuit to the mic
> line and supply the bias externally.

I'm not clear what you mean by the Elecraft K3 method here; are you
saying that there is a DC path from input pin of the first active
element in the rig's microphone amplifier, or are you simply saying that
the bias is injected at the plug end of the cable. In the latter case,
this is also the technique used by typical PC sound card/electret
microphone combinations. Although the bias is fed to the ring in the
jack, the ring and tip are actually interconnected. (I think the reason
for this is so that the same socket will work with dynamic microphones,
with a mono jack.)

I've checked the schematics, and there doesn't seem to be a DC path.

>
> The power adder consists of a capacitor between the mic element and the

In the case of the K2, that capacitor is internal to the rig, but does
exist. It's also the case for the K3, the capacitor is C17 on the third
page of the KIO3 schematic.

(It may well make a difference at RF, where the inductance of the cable
is signficant.)

> Yaesu/TenTec/Flex-radio) or even a battery. The resistor is not there
> for voltage dropping, it is there to limit the current to the mic
> element to a safe value and to prevent the internal impedance of the

As I understand the way that electret microphones work, you must not use
a resistor value that effectively limits the current, as the FET would
be operating in its cutoff region, which is not the ideal region in
which to operate (although not as bad as bipolar transistors, which
would have particularly bad second harmonic distortion).

> power supply, particularly any filter or bypass capacitor, from
> loading the mic (shunting the output).

That's generally true, provided the amplifier input impedance is
relatively low. If its high, the need to avoid cutting off the FET will
limit the value of feed resistor and it may actually become the
effective load on the microphone.

The ideal power feed would have very high AC impedance and very low DC
resistance, but a choke would be much more expensive than a resistor, to
the extent that it is not even really worth analyzing whether the
circuit would be stable, and immune from mains hum.

--
David Woolley
Emails are not formal business letters, whatever businesses may want.
RFC1855 says there should be an address here, but, in a world of spam,
that is no longer good advice, as archive address hiding may not work.
_______________________________________________
Elecraft mailing list
Post to: [hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com