Elecraft › [K3]

FLx GN Adding Db gain

Classic

List

Threaded

3 messages Options

Craig Smith

FLx GN Adding Db gain

I have the full range of filters, from 13 KHz to 200 Hz and found that there
isn't enough adjustment range to get them all exactly equalized. That is,
with the 2.7 KHz set to 0 (minimum possible) and the 200 Hz set to +8dB
(maximum possible) the 200 Hz was still 2 dB down from the 2.7KHz. So what
I did was to equalize the three filters that I use for CW (my primary mode
of operation) at one value and equalize the 13KHz and 2.7KHz filters at
another value (used for MW, SW listening, etc). This seems to work out
quite well in practice. Here is what I ended up with. The first column is
the variation in dB with the AGC off. The second is with the AGC on. I
used a signal generator and the K3 built-in audio voltmeter for the
measurement.

Filter w/o AGC w AGC
13 K -0.5 -0.1
2.7 K 0 0
1.0 K -2.1 -0.4
500 H -1.5 -0.3
200 H -2.0 -0.4

73
... Craig AC0DS

_______________________________________________
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

dave.wilburn

Re: FLx GN Adding Db gain

Could the built in two tone generator be used as an input for this?
Now to download the latest manual and read about the "audio voltmeter"
I did not realize it had. ;)

David Wilburn
NM4M

Craig D. Smith wrote:

> I have the full range of filters, from 13 KHz to 200 Hz and found that there
> isn't enough adjustment range to get them all exactly equalized. That is,
> with the 2.7 KHz set to 0 (minimum possible) and the 200 Hz set to +8dB
> (maximum possible) the 200 Hz was still 2 dB down from the 2.7KHz. So what
> I did was to equalize the three filters that I use for CW (my primary mode
> of operation) at one value and equalize the 13KHz and 2.7KHz filters at
> another value (used for MW, SW listening, etc). This seems to work out
> quite well in practice. Here is what I ended up with. The first column is
> the variation in dB with the AGC off. The second is with the AGC on. I
> used a signal generator and the K3 built-in audio voltmeter for the
> measurement.
>
> Filter w/o AGC w AGC
> 13 K -0.5 -0.1
> 2.7 K 0 0
> 1.0 K -2.1 -0.4
> 500 H -1.5 -0.3
> 200 H -2.0 -0.4
>
> 73
> ... Craig AC0DS
>
>
>
> _______________________________________________
> 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

dave.wilburn

Re: FLx GN Adding Db gain

In reply to this post by Craig Smith

If I could ever get enough time to get my shack cleaned up, I would
use mine too. But for the moment it is "stealthily concealed". Yea,
thats it.

The advantage of the two tone generator, is I can't loose it. It
seems that if the same tone is used, it would be fine. But then again
it is not going to work on CW mode. Hrrmph.

Now to plan B. Thanks and 73

David Wilburn
NM4M

Craig D. Smith wrote:

> I don't know about using the two tone generator. I used an external XG-2
> module.
>
> The info on the voltmeter can be hard to locate in the manual. In the Rev D
> manual it is on page 36 under "Alternate VFO B displays"
>
> 73
> .... Craig AC0DS
>
> Craig D. Smith
> PowerSmith Consulting
> 1009 Alder Way
> Longmont, CO 80503
> phone: 303-678-7958
> email: [hidden email]
> web: www.PowerSmithConsulting.com
>
>
> <> -----Original Message-----
> <> From: [hidden email]
> [mailto:[hidden email]]
> <> On Behalf Of David Wilburn
> <> Sent: Wednesday, November 12, 2008 8:10 AM
> <> To: Elecraft Discussion List
> <> Subject: Re: [K3] [Elecraft] FLx GN Adding Db gain
> <>
> <> Could the built in two tone generator be used as an input for this?
> <> Now to download the latest manual and read about the "audio voltmeter"
> <> I did not realize it had. ;)
> <>
> <> David Wilburn
> <> NM4M
> <>
> <>
> <>
> <>
> <> Craig D. Smith wrote:
> <> > I have the full range of filters, from 13 KHz to 200 Hz and found that
> there
> <> > isn't enough adjustment range to get them all exactly equalized. That
> is,
> <> > with the 2.7 KHz set to 0 (minimum possible) and the 200 Hz set to +8dB
> <> > (maximum possible) the 200 Hz was still 2 dB down from the 2.7KHz. So
> what
> <> > I did was to equalize the three filters that I use for CW (my primary
> mode
> <> > of operation) at one value and equalize the 13KHz and 2.7KHz filters at
> <> > another value (used for MW, SW listening, etc). This seems to work out
> <> > quite well in practice. Here is what I ended up with. The first
> column is
> <> > the variation in dB with the AGC off. The second is with the AGC on.
> I
> <> > used a signal generator and the K3 built-in audio voltmeter for the
> <> > measurement.
> <> >
> <> > Filter w/o AGC w AGC
> <> > 13 K -0.5 -0.1
> <> > 2.7 K 0 0
> <> > 1.0 K -2.1 -0.4
> <> > 500 H -1.5 -0.3
> <> > 200 H -2.0 -0.4
> <> >
> <> > 73
> <> > ... Craig AC0DS
> <> >
> <> >
> <> >
> <> > _______________________________________________
> <> > 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
>
>
>