Topics

moderated TS-890 or K4?

Andy k3wyc
 

The recently announced Elecraft K4 may provide some competition for the TS-890.   I wonder how soon we will see test data for it.  I suspect it may be a while.

https://elecraft.com/products/k4-transceiver

73,
Andy, k3wyc

Rob Sherwood
 

Considering the nominal first ship date is November, assuming nothing slips, yes it will be quite a while.  Rob, NC0B

 

From: TS-890@groups.io [mailto:TS-890@groups.io] On Behalf Of Andy k3wyc
Sent: Saturday, May 18, 2019 9:44 AM
To: TS-890@groups.io
Subject: [TS-890] TS-890 or K4?

 

The recently announced Elecraft K4 may provide some competition for the TS-890.   I wonder how soon we will see test data for it.  I suspect it may be a while.

https://elecraft.com/products/k4-transceiver

73,
Andy, k3wyc

 


If this email is spam, report it to www.OnlyMyEmail.com

Robert Needleman
 

The advantage that the 890 has over the K3/K3S and new K4, IMO,  is the more user-friendly front panel ergonomics. Lots of knobs on the 890 make for easy access for commonly used operations, such as PO setting, along with the very useful, assignable 3 PF keys.  I've owned the K3 and what you have to do is get used to having many push buttons that serve multiple functions, pressing them quickly or holding them in to get into the secondary function. There are very few knobs as we have on the 890, and it looks like the new K4 will be the same way, not to mention having to devote some of the front panel to the 2nd receiver that looks like will be standard in the K4 (it's an option in the K3/K3S). I'm sure the K4 will have excellent Rx specs, as does the K3/K3S, so again for many operators it will come down to best fit for each individual's needs. By the time the K4 starts shipping (I believe I read that they don't expect the K4 to be shipping until towards the end of the year), the price differential between the 890 and K4 will likely be around $1K-$1.5K, depending on which version of K4 you are interested in, so another issue that needs to be considered, unless money is no object! I am glad to see Elecraft designing and making available a brand new radio with a totally different, modern architecture (SDR) vs. the K3/K3S transceiver, which has been around for many years and getting a bit 'long in the tooth'. I wish the folks at Elecraft much success and hope it will be a winner for them so they can survive in a pretty competitive HF transceiver market that has developed among the Japanese, US and Russian amateur manufacturers.

Bob, K3AC

In a message dated 5/18/2019 10:14:38 PM Eastern Standard Time, rob@... writes:

Considering the nominal first ship date is November, assuming nothing slips, yes it will be quite a while.  Rob, NC0B

 

From: TS-890@groups.io [mailto:TS-890@groups.io] On Behalf Of Andy k3wyc
Sent: Saturday, May 18, 2019 9:44 AM
To: TS-890@groups.io
Subject: [TS-890] TS-890 or K4?

 

The recently announced Elecraft K4 may provide some competition for the TS-890.   I wonder how soon we will see test data for it.  I suspect it may be a while.

https://elecraft.com/products/k4-transceiver

73,
Andy, k3wyc


 


If this email is spam, report it to www.OnlyMyEmail.com

Mark van Wijk
 

I would be more interested in the quality of 'Sound Reproduction' , as Rob once called it.

Back in 2009 I discovered how badly SDR could be both for SSB and more at CW between SDR rigs and pure analog.
Badly as in can hear cannot ear DX, or QSo vs no QSO possible
SDR hybrid rigs as in Icom 7400/756ProII and ProIII series, two Elecraft K3 and an TT ORION
Full ADC rig: Perseus SDR  with sw filtering optimized for minimal ringing
Analog as in Elecraft K2 and Drake R-4C

Over the months I created several comparison test setups where  two differnt testsignals were created:
1) continous RF signal from an RF generator (Marconi 2955)
2) A modulated RF signal  from the same generator 'dit-dit-dit-dit' signal
Both were fed via an external step attenuator was either directly to the DUT or via RF on the air (antenna wire at the generator, RX outdoor antenna on the DUT)

Using the step-attenuator I found that 
3) at a steady testsignal the Icoms would offer the best MDS
4) modulating the RF generator the K3 would lag behind the K2, all Icoms would perform up to 8 dB worse, especially in real-life situations where there is band noise.

For sure this anomaly had me for some time and I extended the test with more rigs, repeated building and testing the setups just to be sure.
I invited a hamradio friend who clearly proved again and again he was able to hear signals in the noise about 1 dB better than me (that is kinda frustrating but also proves something).
we continued the test for several weeks to find out what kind of receiver setting was best per model to dig out MODULATED signals out of the noise.  The Icoms would perform less worse when you do not select their DSP BPF but use double PBT to close the BW to abt 100Hz (sweet spot) but with  relatively wide skirts. Something the Icom webpage from Adam describes as well. I used that trick for working DX on 6m for years.
We also looked at the(DSP/analog) filter curves as measured on the audio output.  We also looked at the part 3000Hz -15000 kHz.

Anyway, our conclusions:

5) The current concept of measuring MDS, when used for interpretating readability, is WRONG.  Test methodologies SHOULD use MODULATED test signals.

6) Pure analog receivers are much better at producing audio where weak modulated signals CAN be heard

7) SDR hybrids perform worse in comparison at modulated weak signals whatever SDR settings are tried

8) Filter shape can be a reason for the found differences. Sharp cornered curves perform worse. Round analog shapes perform better
This was positively countered at the  Icom=> using double PBT for IF shape, Perseus=>modify filterpoles down to 32.

results can be found at :  https://pa5mw.blogspot.com/2009/12/upgrade-current-vhf-station-iv-mds.html

DSP shape curve differences also turned up at TT ORION  sw 1.x vs 2.x/3.x. The first generation showed a more round analog shape with slightly wider skirts than the later generations 2.x/3.x
At my TT ORION's there always was a distinct audible difference between sw generation 1 vs 2.x and 3.x  Over the years I have had a total of 4 Orion's (Orion and Orion II), still own 3 of them. 
For weak signal detection on 160m I still prefer sw 1.x over newer generations. Never understood why, untill I was recently told by N4PY that generation 1 was designed by a different engineer.

No one ever was interested to discuss the meaning of MDS.  Horse-power is horse-power. Whether you can use it on the track effectively for forward movement seems hardly of interest. No one ever wanted to look into this.

Getting back on topic;  for me it will be important if the K4 is able to reproduce audio from weak signals on the air. 

73 Mark PA5MW
 

Robert Needleman
 

Much of your discussion is now more of academic interest only, since with modern DNR circuitry, the reduction in background noise greatly improves SSB and CW readibility at low signal strength. One of the best that I've had a chance to use is made by Apache Labs (Anan - full SDR) - activating the NR circuitry is so effective in reducing background noise that it makes the received signals (SSB, CW, whatever you're receiving) 'pop out' of the ether - almost like you're listening to VHF/UHF FM. Flex's (full SDR architecture) is good but not quite up to Anan. The Japanese and US manufacturers (Elecraft is the only one left now that TenTec is defunct) have all incorporated DNR circuits which greatly improve accuracy of low signal reception, and have been improving their circuitry continuously, although I would have to say Icom may be a bit ahead of Yaesu and Kenwood, but not by much. Much of what is  required to receive and efficiently copy low amateur signals, especially SSB, is often dependent on how the audio is being heard - through headphones vs speakers, DSP/IF filter settings, and other filtering including notch/PBT. But I would have to say, in general, that the effective use of DNR has greatly improved low signal work, and I'm sure Elecraft in their new K4 will have designed very effective NR circuitry as the K3/K3S has probably the most capabilities of choosing various NR options of any amateur transceiver on the market.


Bob, k3AC

In a message dated 5/19/2019 5:37:22 AM Eastern Standard Time, pa5mw@... writes:

I would be more interested in the quality of 'Sound Reproduction' , as Rob once called it.

Back in 2009 I discovered how badly SDR could be both for SSB and more at CW between SDR rigs and pure analog.
Badly as in can hear cannot ear DX, or QSo vs no QSO possible
SDR hybrid rigs as in Icom 7400/756ProII and ProIII series, two Elecraft K3 and an TT ORION
Full ADC rig: Perseus SDR  with sw filtering optimized for minimal ringing
Analog as in Elecraft K2 and Drake R-4C

Over the months I created several comparison test setups where  two differnt testsignals were created:
1) continous RF signal from an RF generator (Marconi 2955)
2) A modulated RF signal  from the same generator 'dit-dit-dit-dit' signal
Both were fed via an external step attenuator was either directly to the DUT or via RF on the air (antenna wire at the generator, RX outdoor antenna on the DUT)

Using the step-attenuator I found that 
3) at a steady testsignal the Icoms would offer the best MDS
4) modulating the RF generator the K3 would lag behind the K2, all Icoms would perform up to 8 dB worse, especially in real-life situations where there is band noise.

For sure this anomaly had me for some time and I extended the test with more rigs, repeated building and testing the setups just to be sure.
I invited a hamradio friend who clearly proved again and again he was able to hear signals in the noise about 1 dB better than me (that is kinda frustrating but also proves something).
we continued the test for several weeks to find out what kind of receiver setting was best per model to dig out MODULATED signals out of the noise.  The Icoms would perform less worse when you do not select their DSP BPF but use double PBT to close the BW to abt 100Hz (sweet spot) but with  relatively wide skirts. Something the Icom webpage from Adam describes as well. I used that trick for working DX on 6m for years.
We also looked at the(DSP/analog) filter curves as measured on the audio output.  We also looked at the part 3000Hz -15000 kHz.

Anyway, our conclusions:

5) The current concept of measuring MDS, when used for interpretating readability, is WRONG.  Test methodologies SHOULD use MODULATED test signals.

6) Pure analog receivers are much better at producing audio where weak modulated signals CAN be heard

7) SDR hybrids perform worse in comparison at modulated weak signals whatever SDR settings are tried

8) Filter shape can be a reason for the found differences. Sharp cornered curves perform worse. Round analog shapes perform better
This was positively countered at the  Icom=> using double PBT for IF shape, Perseus=>modify filterpoles down to 32.

results can be found at :  https://pa5mw.blogspot.com/2009/12/upgrade-current-vhf-station-iv-mds.html

DSP shape curve differences also turned up at TT ORION  sw 1.x vs 2.x/3.x. The first generation showed a more round analog shape with slightly wider skirts than the later generations 2.x/3.x
At my TT ORION's there always was a distinct audible difference between sw generation 1 vs 2.x and 3.x  Over the years I have had a total of 4 Orion's (Orion and Orion II), still own 3 of them. 
For weak signal detection on 160m I still prefer sw 1.x over newer generations. Never understood why, untill I was recently told by N4PY that generation 1 was designed by a different engineer.

No one ever was interested to discuss the meaning of MDS.  Horse-power is horse-power. Whether you can use it on the track effectively for forward movement seems hardly of interest. No one ever wanted to look into this.

Getting back on topic;  for me it will be important if the K4 is able to reproduce audio from weak signals on the air. 

73 Mark PA5MW