[TenTec] My own little "quiet test"

[George, W5YR]

Thanks for the quotes, Tim. Just the added thought that the filters, both
IF and audio, on the K2 are not all that sharp compared to the PRO DSP
filters. Also, the K2 has quite a noticeable roll-off at both ends of the
audio spectrum. The PRO is flat from about 80 Hz to 3600 Hz. So, it has the
high-frequency response required to make noise have that crisp, brittle
"percussive" sound while the K2 filters out the highs and the lows and
makes it sound "softer." Now, that is fine if you just want to listen to
noise, but where the rubber meets the road on HF is not in dealing so much
with noise itself as it is in dealing with how the filtering reacts to the 
noise when it is concurrently dealing with nearby strong signals. There the
inherent superiority of the DSP near-ideal filters comes into play. 

I agree with you that it is remarkable that a rig as complex as the PRO can
be as relatively quiet as it is. When comparing a K2 against my PRO I
always found signals easier to copy (CW) on the PRO, especially with any
degree of QRM present regardless of signal strength.

73/72/oo, George W5YR - the Yellow Rose of Texas         
Fairview, TX 30 mi NE of Dallas in Collin county EM13qe   
Amateur Radio W5YR, in the 56th year and it just keeps getting better!
QRP-L 1373 NETXQRP 6 SOC 262 COG 8 FPQRP 404 TEN-X 11771 I-LINK 11735
Icom IC-756PRO #02121  Kachina 505 DSP  #91900556  Icom IC-765 #02437

All outgoing email virus-checked by Norton Anti-Virus 2002


Tim and Nancy Logan wrote:
> 
> Hi folks - earlier George wrote the two paragraphs below. When using my
> K2 or 756 PRO I rarely if ever have the RF gain anywhere but on "full".
> When I had my Omni I used it quite a bit. Anyway, when I got home from
> work today I unhooked the antenna from each rig and listened to them
> with the RF on full and then in turn hooked up the antenna (same antenna
> on each rig). As George points out, reconnecting the antenna increases
> the noise level. What I found interesting was that for practical
> operating purposes the "noise" sounded very similar from each rig.
> Unless you are diliberately focusing on differences, you would not give
> the difference a second thought. It's perhaps appropriate to say that I
> use a horizontal loop (about 260 feet of it) which is a fairly quiet
> antenna. It is really too bad that I did not still have the OMNI to
> compare it the other two. Since I am a true Elecraft nut it is a bit
> tuff for me to admit that I think the PRO is a darn good rig with no
> excessive noise that my ears can detect. I certainly don't have 1/100th
> the knowledge that many of you have, but I can share my real world
> experiences - and I thought this was interesting. The K2's "noise" might
> be a little "softer" for lack of a better word. Neither rig creates what
> I would subjectively describe as a roar. To me, the big differenc at the
> operating level between these two types of rigs is the sound of the cw.
> For lack of a better word, it is a bit more "percussive" on the PRO -
> but to me that means nothing. Just thought you might find this
> "layman's" experience interesting. 73/Tim NX7C