[Elecraft] My K3's Very Quiet

[Jan Erik Holm]

Hmm, interesting, 4 dB MDS improvement and the gain of the
preamp is 15-20 dB i think. Spontaneously this is a lousy
preamp or I had too much too drink during  Saturday dinner.

Correction to W0SD:

The FT-1000D DO have a preamp, about20 dB gain. Check the
schematic and you will see. When you turn switch to IPO it
kicks out the preamp. Then turning it further to 6 dB etc etc
you switch in attenuation in 6 dB steps. IMO this was soo stupid, 
instead I did modify my FT-1000D NOT to turn off preamp but just
use the atennuation steps. Easy to do, just look at the schematic.
By using the 6 12 18 dB attenuation steps I easily can improve
the IMDDR3 when needed. My modified FT-1000D has about 92 dB
IMDDR3 at a MDS of about 142 dB 2 kHz spacing. Not too shabby,
and I don´t have to "ride the" RF gain. Also I don´t get fatigued by 
strange pink or whatever noise.

Soo here we have a radio ( K3 ) with 135 dB MDS and you guys
are going to lower the gain! In my head something is totally
wacky here.

/ Jim SM2EKM
------------------------
drewko wrote:
> Regarding the preamp: MDS measurements show a better (S+N)/N with the
> preamp on, approx 4 db improvement in MDS on my K3 on 40m. A similar
> improvement is obtained by setting the ATU to BYPASS. 
> 
> The macro to toggle Preamp+Bypass is SWH19;SWT24; for anyone who wants
> to try it. It may be useful for weak signals. You do have to remember
> to toggle it (the ATU) back on when you transmit though.
> 
> 73,
> Drew
> AF2Z
> 
> 
> On Sat, 19 Dec 2009 10:27:16 -0600, Ed W0SD wrote:
>> It has been my experience over the years to "NOT" use the pre-amp on any 
>> HF radio unless you are out of audio gain.  The FT-1000D did not have  a 
>> pre-amp and the only place for me it was lacking was 10 meters.  For me 
>> I just don't hear more at 10 meters and down  with a pre-amp.  For me it 
>> just brings the noise up with the signal.  The only place I have seen a 
>> big benefit from a pre-amp is above 28 mhz.  Obviously the K3 benefits 
>>from a pre-amp on six meters.
>> Ed W0SD
>