James,
I guess you have a poor memory or were not paying attention.
Jim already forwarded us one mail in which N6TV specifically addressed the
issue with the 590.
That was two years ago.
I will reprint it below...
James, there are people who understand how this technology work.
You don't seem to accept anyone's explanation.
As for K3LR and the ICOMs, well not all ICOMs have noisy transmitters. But
the cheap ones do, including the 7600 - even though it is not cheap. The
more expensive ones are better.
I know Tim has (or had) at least one 7600 on site. Keep in mind K3LR works
with several external band filters (on the TX side) which reduce any signal
(including broadband noise) outside of their bandpass by about 30 dB. If
you remove these filters, it would be a different story.
A set of filters for all bands will run you about a grand, so you can buy
your cheap transceiver, add in 1000 bucks for external filters, and then
have a clean signal.
In addition, K3LR does not run commercial amps. The amps are home-brew
monoband amplifiers with additional filtering to help maintain as clean of
signal as possible, so as not to disturb the other team members.
Sorry mate, the reference to K3LR was a poor example!
73 - Rick, DJ0IP
(Nr. Frankfurt am Main)
--------------------------------
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Jim Brown
Sent: Monday, October 08, 2012 10:21 PM
To: tentec@contesting.com
Subject: Re: [TenTec] OT: Question about TS-590 possible problem
On 10/7/2012 1:10 AM, Rick - DJ0IP / NJ0IP wrote:
> We are simply asking for experience with the TS-590.
> I'm thinking the TS-590 is a random noise generator!
YES, it is. So is the Icom 7600. These are low cost, do-everything
wonders, and the design compromises to do everything at low cost results in
lots of broadband noise. There are good reasons why much cleaner rigs like
the Orion and K3 cost a lot more.
Below is a post by N6TV (top contester, owns several K3s) to the NCCC
reflector back in July. Note specifically the comments about the 590.
73, Jim K9YC
= = = = = = = = = = =
On Mon, Jul 16, 2012 at 3:55 PM, KE1B <ke1b@richseifert.com
<mailto:ke1b@richseifert.com>> wrote:
OK, so now you've got my interest. Why would CW-QRQ (a *transmit*
function), cause RIT, IF SHIFT, etc. functions (all on the receiver)
to be disabled?
This is kind of a long and complicated story, and should probably move to
another reflector.
The original K3 firmware didn't have a CW jitter problem at speeds >37 WPM,
but some K3s had a little chirp. Elecraft fixed the chirp by changing the
timing: they added more DDS "settling time". That fixed the chirp, but
introduced CW jitter (erratic CW timing at >37 WPM).
Then Elecraft added CW QRQ mode to fix the jitter, but this has the noted
restrictions, which are a side effect of locking the DDS.
***** Other radios like the TS-590S don't have the same issue because they
use a method of frequency locking that produces much more phase noise during
transmit (DDS without cleaning up the signal with a PLL).The Elecraft
engineers have decided it is far more important to have super clean output,
with some restrictions above 37 WPM, than to have noisy jitter-free CW
without restrictions at all speeds. These are difficult engineering
trade-offs. In densely-populated SCV, I think it is especially important
for all to have super-clean, noise-free, click-free CW.
*****
73,
Bob, N6TV
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