Re: Mics for K3

classic Classic list List threaded Threaded
3 messages Options
Reply | Threaded
Open this post in threaded view
|

Re: Mics for K3

Robert C.Abell
Attn. DW Holtman,

I too have and use the Astatic 7077 mic for my Drake TR-7 and have a D-104 for my
Collins KWM-2A. I doubt that they will work with an Elecraft K3. They are high impedence
mics and the K3 would need a low impedence mic.
You may be able to hook them up through a matching transformer however.
IMHO.

73, Bob  VE3XM
_______________________________________________
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
Reply | Threaded
Open this post in threaded view
|

RE: Re: Mics for K3

Joe Subich, W4TV-3


> You may be able to hook them up through a matching
> transformer however.

You could also use a simple one or two FET/Transistor
preamplifier/buffer powered by the electret bias.  There
are several such circuits floating around for the D-104.
They would require only minor modifications to use bias
on the mic lead instead of a separate wire or battery.

73,

   ... Joe, W4TV
 



> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of Robert C.Abell
> Sent: Wednesday, January 30, 2008 12:11 PM
> To: [hidden email]
> Cc: [hidden email]
> Subject: [Elecraft] Re: Mics for K3
>
>
> Attn. DW Holtman,
>
> I too have and use the Astatic 7077 mic for my Drake TR-7 and
> have a D-104 for my
> Collins KWM-2A. I doubt that they will work with an Elecraft
> K3. They are high impedence
> mics and the K3 would need a low impedence mic.
> You may be able to hook them up through a matching
> transformer however.
> IMHO.
>
> 73, Bob  VE3XM
> _______________________________________________
> 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
Reply | Threaded
Open this post in threaded view
|

Re: Re: Mics for K3

Robert Brigham
In reply to this post by Robert C.Abell
Bob et. al..,
I am in the process of matching my D-104 to my K2 with
a darlinton transistor emitter follower circuit to
bring the roughly 250kOhm element impedence down to
about 600 ohms. Got it to work fine with the  K2
running QRP, but everything goes
to-hell-in-a-handbasket once I ramp up the power. I'm
powering the circuit off of the +5Vv pin the mic jack.
I've grounded the mic jack shield and inserted a
cap+toroid inductor filter on the +5v. This got the
QRP version on the air, but I clearly have to do more
when running 100w. So, if you can get the job done
with just a transformer, that may be the simplest
solution [and if you locate a good transformer forward
the part number :) ].
Rob
KC6ROC
K2/100 #5924
--- "Robert C.Abell" <[hidden email]> wrote:

> Attn. DW Holtman,
>
> I too have and use the Astatic 7077 mic for my Drake
> TR-7 and have a D-104 for my
> Collins KWM-2A. I doubt that they will work with an
> Elecraft K3. They are high impedence
> mics and the K3 would need a low impedence mic.
> You may be able to hook them up through a matching
> transformer however.
> IMHO.
>
> 73, Bob  VE3XM
> _______________________________________________
> 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
>



      ____________________________________________________________________________________
Never miss a thing.  Make Yahoo your home page.
http://www.yahoo.com/r/hs
_______________________________________________
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