K2/100 #4001

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

K2/100 #4001

bill linn
Since building the 100 watt add on, I have been venturing into a bit of SSB.
The mic jack is wired for Kenwood and the mic I'm using is a hand mic that
came with the TS 570, a dynamic with 600 ohm impedance.

I don't think the ALC (Talc) action is working properly.   With the mic gain
set at 3 and the compression ratio at 4-1 the ALC lights up 3 bars.   These
settings are extreme and the on the air audio is "Breathy" with lots of
background noise.   Not good.    But, even at these extreme settings,
power-output seems low and restrained.

I've tried every possible combination of mic gain/compression.  On the low
end, mic at 1 and compression off, there is no indication of ALC on the bar
and the power indication is very low.  Only with the power set to 0.01 does
the ALC respond at a sensitivity that seems appropriate with the mic set at
1 and compression off.

I'd like to hear from others what their experience is with various mics and
mic settings, troubles and remedies, etc.
Thanks,
Bill  -  W7WEL

_______________________________________________
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: K2/100 #4001

Ron D'Eau Claire-2
Bill, W7WEL wrote:

Since building the 100 watt add on, I have been venturing into a bit of SSB.
The ...mic I'm using is a hand mic that came with the TS 570, a dynamic with
600 ohm impedance.

I don't think the ALC (Talc) action is working properly.   With the mic gain
set at 3 and the compression ratio at 4-1 the ALC lights up 3 bars.   These
settings are extreme and the on the air audio is "Breathy" with lots of
background noise.   Not good.    But, even at these extreme settings,
power-output seems low and restrained.

I've tried every possible combination of mic gain/compression.  ...I'd like
to hear from others what their experience is with various mics and mic
settings, troubles and remedies, etc.
----------------------------------

Bill, if your ALC is flickering even one bar, you are hitting the full peak
output you have the POWER control set for. MIC 2 and MIC 3 are identical
gains. Only MIC 1 is different. It inserts about 10 dB of gain. The number
of ALC bars lighting only indicates how much gain reduction the AGC has to
use to hold the output power down to your requested level. More or less bars
do not mean more or less output as long as at least one bar is flashing.

The presence of a lot of background noise suggests that you have plenty of
mic gain anyway - assuming that's what others are hearing with nominal
signal strengths. Background noise will sound much louder on a nearby
monitor receiver because of the huge signal level at such close range.

I'm not real sure what you mean by "restrained" but one thing a lot of ops
with K2's on SSB miss is that note in the KSB2 manual to adjust the BFO
frequencies for best reproduction of your voice. Setting them by Spectrogram
gets them close enough for a lot of ops, but there's nothing like actually
hearing your own signal. If you can, listen on an auxiliary receiver and
record it, then play back the recording. You may find that shifting the BFO
frequency a bit one way or the other will do a lot to improve the quality of
your audio beyond the basic setting looking at Spectrogram.

Ron AC7AC


_______________________________________________
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: K2/100 #4001

Ron D'Eau Claire-2
AARGH!!

Mic 1 inserts about 10 dB of ATTENUATION, not gain. Where's my egg-nog
refill???

Happy Holidays to you all!

Ron AC7AC

-----Original Message-----
---------------------------------

Bill, if your ALC is flickering even one bar, you are hitting the full peak
output you have the POWER control set for. MIC 2 and MIC 3 are identical
gains. Only MIC 1 is different. It inserts about 10 dB of gain....


_______________________________________________
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: K2/100 #4001

Ian Maude
In reply to this post by bill linn
On Fri, 2004-12-24 at 11:09 -0800, bill linn wrote:
> Since building the 100 watt add on, I have been venturing into a bit of SSB.
> The mic jack is wired for Kenwood and the mic I'm using is a hand mic that
> came with the TS 570, a dynamic with 600 ohm impedance.
Hi Bill,
I did exactly the same thing when I first used the K2 on SSB.  I had to
play around a bit to get it right.  First, I changed R14 on the SSB
module from 1K to 5K6.  This makes more of a difference than you think,
try it.  Secondly, grab a Heil insert and fit it into the mic housing
instead of the one Kenwood put there.  I use the HC5.  Then, as has been
suggested, run OP1 through spectrogram to centre the filter.
I would also do the 2.4kHz bandwidth mod on the SSB board, it is only a
few capacitors.

I did all of this and my audio gets lots of unsolicited compliments.  In
fact, someone told me the other day that the quality was as good as my
wifes when she was on the 1000MP using a desk mic!  I suspect my voice
was a little deeper however ;-)

The ALC will look exactly the same after all of this but you will see a
higher average output without having to be right up to the mic.

Happy Christmas and have fun!

Ian

--
Ian Maude G0VGS Morecambe Lancs UK | [hidden email]
Sysop of GB7MBC, the Morecambe Bay Cluster
Running Linux and DXSpider | K2 #4044
 
Find out about Summits on the Air!  
Visit the SOTA web site at http://www.sota.org.uk

_______________________________________________
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