Re: [Elecraft] Price Comparison and Comment

2007-05-05 Thread Bill Tippett



--- Don Wilhelm <[EMAIL PROTECTED]> wrote:

> Bill,
>
> All of what you say is true *EXCEPT* for one item -
> and that is the AGC.
>
>
[...]

> Now, if the signal you are trying to copy is an S-1
> or S-2 level and an
> S-9 signal comes into the roofing filter passband
> (again it may be out
> of the DSP passband and will not be heard), the
> receiver gain will be
> reduced and you will no longer hear the S-1/S-2
> signal - just like QSB,
> but it is QSB induced in the receiver, not due to
> propagation effects.


VA7W:

Ek! time to kill the agc and back down on the RF
gain and up the audio gain?


To some degree but you cannot actually kill AGC
in a rig like Orion (or perhaps K3 which apparently uses
similar analog plus digital AGC).  The reason is that the
analog AGC (actually more of a peak limiter) ahead of
the DSP must *always* be active to protect the DSP
from being over-driven.

Your "Ek!" sound is a good description
of the sound of a DSP that is over-driven.  In Orion
digital AGC in the DSP is also never fully turned off.
"Off" is simulated by setting AGC Decay to a high
rate (1000 dB/s) but it is never actually off even when
"Off" is selected on the front panel.  I've discovered I
can make it a little more "Off" by setting Decay to
2000 dB/s in the Programmable AGC mode, but that
is also not truly "Off" (which has an infinitely fast
decay rate).

We can basically throw away some of our
ideas about AGC based on analog rigs like the
K2.  DSP rigs simply don't work the same way.
I'll repeat again...I've never heard classical AGC
pumping in Orion.  If you are using a 500 Hz filter
(+/- 250 Hz BW) and a S9+30 station is 500 Hz
away (then attenuated ~6 dB by the filter skirt),
you will hear keyclicks, phase noise, etc long
before you hear AGC problems.  Also "pumping"
is not a good description of a signal overdriving a
DSP.  To me It sounds more like a machine gun
suddenly going off next to your head.  It's more
of a digital (i.e. on/off) staccato effect...not the
classical analog gain pumping effect.

73,  Bill  W4ZV


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Re: [Elecraft] Price Comparison and Comment

2007-05-05 Thread Geoffrey Mackenzie-Kennedy
Keep up the good work Bill!!  May I second you request for comprehensive IMD 
/ BDR  test results. Crystal filters, particularly ladders, do have a habit 
of coming back to bite unless their linearity, or lack of, is taken into 
account while setting Gain Distribution et al during the design activity.


I sometimes wonder whether the use of wide SSB filters e.g  2.7 kHz in our 
ham community is due to poor narrower filter design,  and the reulting group 
delay characteristic. This in turn can result in a SSB voice signal having a 
"raspy" sound. In my opinion based on observation and use, 2.1 kHz  is 
enough for very good soundimg audio IF things are set up properly (carrier 
position, modulator AF drive, ALC, mic, etc, etc),  leaving more spectrum 
for others to use.


73,
Geoff
GM4ESD


On Friday, May 04, 2007 at 7:59 PM, Bill Tippett wrote:


SSB - 2.7 kHz unless you want ESSB (not sure how high
that goes these days but IMHO we should be trying to
minimize communications bandwidths rather than playing
broadcast disc jockey (my personal opinion!).  Those
folks should go to 29 MHz FM if they want to do that.

.


A roofing filter's purpose is simply to minimize
spurious artifacts from being created *inside* the RX
by external signals.  It does NOT create the ultimate
selectivity (which is determined by the DSP filter at
the 2nd IF).  Please read the last sentence again!
Here's a simple summary:





...roofing filter prevents very strong signals from
creating spurious (i.e. *NOT REAL*) signals which
will then appear inside the DSP.





The number of poles (i.e. shape factor of the
filter) can affect IMD/BDR issues inside the RX.  For
this reason hopefully Elecraft will provide actual
IMD/BDR measurements with each option to help answer
the following questions:

1.  Is the optional 8-pole 2.8 kHz better than the
stock 5-pole 2.7 kHz (by "better" I mean resulting
in better IMD/BDR performance which is the primary
purpose of a roofing filter).





The variable BW filters are interesting but
I would not consider them until we have some actual
results for IMD/BDR.  They are NOT providing ultimate
selectivity as they do in the case of the K2, which
seems to be confusing many folks.

73,  Bill  W4ZV



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RE: [Elecraft] Price Comparison and Comment

2007-05-04 Thread Brett gazdzinski
 
You seem to think the only time someone is going to
use wider bandwidths is on a packed band.

I personally only get on 80 or 40 on weekends, in the 
morning, when the band is wide open.

You can say ssb is a waste, since its much wider than
CW.

Brett
N2DTS

> 
> SSB - 2.7 kHz unless you want ESSB (not sure how high
> that goes these days but IMHO we should be trying to
> minimize communications bandwidths rather than playing
> broadcast disc jockey (my personal opinion!).  Those
> folks should go to 29 MHz FM if they want to do that.
> 
> AM - 6 kHz
> 
> FM - 15 kHz
> 
> 

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Re: [Elecraft] Price Comparison and Comment

2007-05-04 Thread Bill Tippett

Hi Don,

At 08:47 PM 5/4/07, Don Wilhelm wrote:

I did ask Wayne about the AGC (with respect to the roofing filter 
selection) and he indicated that the AGC was developed in hardware 
before the A/D conversion and there is additional AGC action created 
in the DSP.  As I understand it, it is similar to that which you 
describe in the Orion.


If it is like Orion's I'll be happy!

Yes, from a receiver performance standpoint, only the A/D overload 
problem counts (and it is critical), but from an operating (AGC 
pumping) standpoint, there can be undesired performance in the 
presence of strong signals that pass through the roofing filter even 
though they are filtered out by the DSP because they will reduce the 
overall gain of the receiver.  Quite apart from the receiver specs, 
it does show up during operation and the AGC pumping can be a real 
problem for weak signal reception regardless of the total dynamic 
range of the receiver.


I'm not sure I agree.  If analog AGC is
not activated, there is no analog gain change or
pumping.  According to the note I posted from
Doug Smith, the DSP can internally handle AGC
within the ballpark of 100 dB (noise floor to S9+40).
It first filters signals digitally and then applies AGC
only to signals appearing within the selected DSP
bandwidth, so there is no pumping by signals
outside the DSP bandwidth...unless I misunderstand
...which is completely possible of course!

All I can say is I have never experienced
the problem in Orion.  I've got to get ready for a
symphony concert now so hopefully all will be
answered in the fullness of time!

73,  Bill


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Re: [Elecraft] Price Comparison and Comment

2007-05-04 Thread w2bvh
Bill,

I've had my eye on the Orion since it came out. I almost got to the point of 
clearing getting one with my xyl, but about that time the QST review came out 
and it wasn't all that kind to the Orion. So I've held on to my K2. I've been 
happy with it, but it's human nature to always look for a bit more.

The reason I'm writing you is I'd like to know if you think the (2) QST reviews 
were unfair and what you think of the Orion... (Your reply, below, is quite 
complimentary; but are you coping with other deficiencies to get the raw 
performace the Orion is giving you?)

Tnx in advance & 73,
Lenny W2BVH
 -- Original message --
From: Bill Tippett <[EMAIL PROTECTED]>
> At 07:34 PM 5/4/07, Don Wilhelm wrote:
> 
> >All of what you say is true *EXCEPT* for one item - and that is the AGC.
> 
>  Don you are absolutely correct.  The reason
> I never considered it is that I have never experienced it
> with my Orion.  I seldom operate with strong signals
> spaced much closer than 500 Hz.  The most severe
> case of this may be in the CQ 160 CW Contest where
> it's not uncommon for S9+20 to 30 signals to be spaced
> every 500 Hz.  With typical key click bandwidths, very
> few people will try to get closer than 500 Hz.  Given
> 500 Hz signal spacing and given a 500 Hz BW filter,
> the filter easily knocks them down to a reasonable
> level, since the filter BW is +/- 250 Hz and the signals
> are +/- 500 Hz.
> 
>  Orion uses a two-stage AGC system, one is
> analog and ahead of the DSP.  It has has the main
> function of preventing over-driving the DSP stage.
> 
> "ADC overload can never be allowed to occur because when that 
> happens, signals are irrevocably corrupted. Signals that are larger 
> than the full-scale range of the ADC must force reduction of gain in 
> the analog section of the receiver. So both analog and digital AGCs 
> are used in the Orion. Resort to analog AGC only need be made when 
> signals inside the roofing bandwidth exceed about S-9 plus 30 dB. At 
> that point, sensitivity is reduced but what we are discovering is 
> that phase-noise performance-- as determined by reciprocal-mixing 
> measurements-- already limits what you can hear. So performance is 
> phase-noise limited and not DSP limited. Even so, the Orion gives you 
> the option of kicking in a crystal filter, preventing movement of the 
> analog AGC and the sensitivity reduction described above."
> 
> http://www.doug-smith.net/orion.htm
> 
>  As stated, this analog AGC does not activate
> until signals reach the S9+35 range.  The second AGC is
> digital and internal to the DSP (which works very well).
> 
> "As the resolution and speed of ADC hardware improve, digital radio 
> receivers become less dependent on analog AGC to meet dynamic-range 
> requirements. State-of-the-art 24-bit IF-DSP converters, such as 
> those used in the Ten-Tec Orion, produce about 100 dB of dynamic 
> range. That means a receiver can handle signals from the noise floor 
> to almost 40 dB over S9 without analog AGC. Above that level, analog 
> AGC is still necessary to maintain the linearity of analog circuits 
> and to prevent overload in the ADC hardware."
> 
> http://www.doug-smith.net/dspdynamics.htm
> 
>  I haven't seen much about the K3 AGC but I
> hope it uses a similar same technique as Orion.  I have
> NEVER heard any AGC pumping in Orion, even under
> severe situations like the CQ 160 CW Contest which
> I consider the ultimate test for any receiver.  I guess
> that's why it did not occur to me to mention it.  Maybe
> one of the Elecraft folk will tell us more abour the K3
> AGC.
> 
>  73,  Bill  W4ZV
> 
> 
> 
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Re: [Elecraft] Price Comparison and Comment

2007-05-04 Thread romers romansky

--- Don Wilhelm <[EMAIL PROTECTED]> wrote:

> Bill,
> 
> All of what you say is true *EXCEPT* for one item -
> and that is the AGC.
> 
>
[...]

> Now, if the signal you are trying to copy is an S-1
> or S-2 level and an 
> S-9 signal comes into the roofing filter passband
> (again it may be out 
> of the DSP passband and will not be heard), the
> receiver gain will be 
> reduced and you will no longer hear the S-1/S-2
> signal - just like QSB, 
> but it is QSB induced in the receiver, not due to
> propagation effects.
> 

Ek! time to kill the agc and back down on the RF
gain and up the audio gain?

Best,
jerome - va7vv

[...]
> 73,
> Don W3FPR
> 

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Re: [Elecraft] Price Comparison and Comment

2007-05-04 Thread Don Wilhelm

Bill,

I did ask Wayne about the AGC (with respect to the roofing filter 
selection) and he indicated that the AGC was developed in hardware 
before the A/D conversion and there is additional AGC action created in 
the DSP.  As I understand it, it is similar to that which you describe 
in the Orion.


Yes, from a receiver performance standpoint, only the A/D overload 
problem counts (and it is critical), but from an operating (AGC pumping) 
standpoint, there can be undesired performance in the presence of strong 
signals that pass through the roofing filter even though they are 
filtered out by the DSP because they will reduce the overall gain of the 
receiver.  Quite apart from the receiver specs, it does show up during 
operation and the AGC pumping can be a real problem for weak signal 
reception regardless of the total dynamic range of the receiver.


We both await the real details on the K3 AGC (and other things too).

73,
Don W3FPR

Bill Tippett wrote:

At 07:34 PM 5/4/07, Don Wilhelm wrote:


All of what you say is true *EXCEPT* for one item - and that is the AGC.


Don you are absolutely correct.  The reason
I never considered it is that I have never experienced it
with my Orion.  I seldom operate with strong signals
spaced much closer than 500 Hz.  The most severe
case of this may be in the CQ 160 CW Contest where
it's not uncommon for S9+20 to 30 signals to be spaced
every 500 Hz.  With typical key click bandwidths, very
few people will try to get closer than 500 Hz.  Given
500 Hz signal spacing and given a 500 Hz BW filter,
the filter easily knocks them down to a reasonable
level, since the filter BW is +/- 250 Hz and the signals
are +/- 500 Hz.

Orion uses a two-stage AGC system, one is
analog and ahead of the DSP.  It has has the main
function of preventing over-driving the DSP stage.

"ADC overload can never be allowed to occur because when that happens, 
signals are irrevocably corrupted. Signals that are larger than the 
full-scale range of the ADC must force reduction of gain in the analog 
section of the receiver. So both analog and digital AGCs are used in the 
Orion. Resort to analog AGC only need be made when signals inside the 
roofing bandwidth exceed about S-9 plus 30 dB. At that point, 
sensitivity is reduced but what we are discovering is that phase-noise 
performance-- as determined by reciprocal-mixing measurements-- already 
limits what you can hear. So performance is phase-noise limited and not 
DSP limited. Even so, the Orion gives you the option of kicking in a 
crystal filter, preventing movement of the analog AGC and the 
sensitivity reduction described above."


http://www.doug-smith.net/orion.htm

As stated, this analog AGC does not activate
until signals reach the S9+35 range.  The second AGC is
digital and internal to the DSP (which works very well).

"As the resolution and speed of ADC hardware improve, digital radio 
receivers become less dependent on analog AGC to meet dynamic-range 
requirements. State-of-the-art 24-bit IF-DSP converters, such as those 
used in the Ten-Tec Orion, produce about 100 dB of dynamic range. That 
means a receiver can handle signals from the noise floor to almost 40 dB 
over S9 without analog AGC. Above that level, analog AGC is still 
necessary to maintain the linearity of analog circuits and to prevent 
overload in the ADC hardware."


http://www.doug-smith.net/dspdynamics.htm

I haven't seen much about the K3 AGC but I
hope it uses a similar same technique as Orion.  I have
NEVER heard any AGC pumping in Orion, even under
severe situations like the CQ 160 CW Contest which
I consider the ultimate test for any receiver.  I guess
that's why it did not occur to me to mention it.  Maybe
one of the Elecraft folk will tell us more abour the K3
AGC.

73,  Bill  W4ZV



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Re: [Elecraft] Price Comparison and Comment

2007-05-04 Thread Bill Tippett

At 07:34 PM 5/4/07, Don Wilhelm wrote:


All of what you say is true *EXCEPT* for one item - and that is the AGC.


Don you are absolutely correct.  The reason
I never considered it is that I have never experienced it
with my Orion.  I seldom operate with strong signals
spaced much closer than 500 Hz.  The most severe
case of this may be in the CQ 160 CW Contest where
it's not uncommon for S9+20 to 30 signals to be spaced
every 500 Hz.  With typical key click bandwidths, very
few people will try to get closer than 500 Hz.  Given
500 Hz signal spacing and given a 500 Hz BW filter,
the filter easily knocks them down to a reasonable
level, since the filter BW is +/- 250 Hz and the signals
are +/- 500 Hz.

Orion uses a two-stage AGC system, one is
analog and ahead of the DSP.  It has has the main
function of preventing over-driving the DSP stage.

"ADC overload can never be allowed to occur because when that 
happens, signals are irrevocably corrupted. Signals that are larger 
than the full-scale range of the ADC must force reduction of gain in 
the analog section of the receiver. So both analog and digital AGCs 
are used in the Orion. Resort to analog AGC only need be made when 
signals inside the roofing bandwidth exceed about S-9 plus 30 dB. At 
that point, sensitivity is reduced but what we are discovering is 
that phase-noise performance-- as determined by reciprocal-mixing 
measurements-- already limits what you can hear. So performance is 
phase-noise limited and not DSP limited. Even so, the Orion gives you 
the option of kicking in a crystal filter, preventing movement of the 
analog AGC and the sensitivity reduction described above."


http://www.doug-smith.net/orion.htm

As stated, this analog AGC does not activate
until signals reach the S9+35 range.  The second AGC is
digital and internal to the DSP (which works very well).

"As the resolution and speed of ADC hardware improve, digital radio 
receivers become less dependent on analog AGC to meet dynamic-range 
requirements. State-of-the-art 24-bit IF-DSP converters, such as 
those used in the Ten-Tec Orion, produce about 100 dB of dynamic 
range. That means a receiver can handle signals from the noise floor 
to almost 40 dB over S9 without analog AGC. Above that level, analog 
AGC is still necessary to maintain the linearity of analog circuits 
and to prevent overload in the ADC hardware."


http://www.doug-smith.net/dspdynamics.htm

I haven't seen much about the K3 AGC but I
hope it uses a similar same technique as Orion.  I have
NEVER heard any AGC pumping in Orion, even under
severe situations like the CQ 160 CW Contest which
I consider the ultimate test for any receiver.  I guess
that's why it did not occur to me to mention it.  Maybe
one of the Elecraft folk will tell us more abour the K3
AGC.

73,  Bill  W4ZV



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Re: [Elecraft] Price Comparison and Comment

2007-05-04 Thread Don Wilhelm

Bill,

All of what you say is true *EXCEPT* for one item - and that is the AGC.

The hardware AGC is developed before any DSP processing, so when there 
are strong signals inside the roofing filter passband, they will 
activate the AGC and reduce the receiver sensitivity.  If you have the 
DSP cranked down to a narrow bandwidth, you may not even hear the 
offending strong signal because it is outside the DSP bandwidth but 
still inside the roofing filter bandwidth.


BTW, this can happen on the K2 (and many other receivers) if a wide 
bandwidth is selected and the DSP is used to reduce the signal to only 
the desired one.


That is not really tough to deal with if you are already listening to an 
S-9 signal even though an S-9 +30 signal comes on - the S-9 signal will 
be reduced to the equivalent of an S-4 or S-5 signal and that can easily 
be solid copy (because other signals in the DSP passband are similarly 
reduced).


Now, if the signal you are trying to copy is an S-1 or S-2 level and an 
S-9 signal comes into the roofing filter passband (again it may be out 
of the DSP passband and will not be heard), the receiver gain will be 
reduced and you will no longer hear the S-1/S-2 signal - just like QSB, 
but it is QSB induced in the receiver, not due to propagation effects.


I will have at least one narrow filter available in my K3.  Bill, you 
were correct that a filter is needed for each major mode, but the 
filters that any one person needs will be determined by their operating 
habits, and not based on the 'average'.  For ragchewing and  casual 
contacts, even the wide 2.7 kHz filter may be all that is needed, but 
for serious CW, QRP, contesting or DX chasing, an array of filters will 
be needed - just how many will depend on the operator's desires to 
reduce QRM and the amount available in the ham radio budget.


73,
Don W3FPR

Bill Tippett wrote:

W5EWA:
 >but now someone says that we DON'T need them all.

Definitely not...unless we have more money than
sense.  You need only ONE per major mode, which will
cover the widest bandwidth you ever expect to use in
that mode.  For example:

CW - 500 or 400.  250 and 200 are definite overkill
IMHO and not necessary in addition to narrow DSP BWs.
The reason is that IMD/BDR spurious issues at <500 Hz
will be far overridden by other issues such as phase noise,
key clicks, etc that come from the transmitted signals.
There is no point in making a receiver many dB better
than the environment in which it must live!  No matter
how good a receiver is it cannot eliminate transmitter
defects (maybe Flex's SDR-X can but that remains to be
proven).

SSB - 2.7 kHz unless you want ESSB (not sure how high
that goes these days but IMHO we should be trying to
minimize communications bandwidths rather than playing
broadcast disc jockey (my personal opinion!).  Those
folks should go to 29 MHz FM if they want to do that.

AM - 6 kHz

FM - 15 kHz

In fact you may not need ANY filters beyond
the 2.7 kHz stock filter unless you expect to have lots
of very close spaced S9+30 dB signals on CW (e.g. huge
low-band pileups or in contests).  The 2.7k should be
perfectly adequate for nearly any situation on SSB,
although it wouldn't surprise me to see someone offer
1.8 kHz, mainly for contesters.

A roofing filter's purpose is simply to minimize
spurious artifacts from being created *inside* the RX
by external signals.  It does NOT create the ultimate
selectivity (which is determined by the DSP filter at
the 2nd IF).  Please read the last sentence again!
Here's a simple summary:


Antenna > roofing filter > DSP filter > ear.

...roofing filter prevents very strong signals from
creating spurious (i.e. *NOT REAL*) signals which
will then appear inside the DSP.

...DSP filters provide the ultimate selectivity (i.e.
separating the *REAL* signals from each other).


The number of poles (i.e. shape factor of the
filter) can affect IMD/BDR issues inside the RX.  For
this reason hopefully Elecraft will provide actual
IMD/BDR measurements with each option to help answer
the following questions:

1.  Is the optional 8-pole 2.8 kHz better than the
stock 5-pole 2.7 kHz (by "better" I mean resulting
in better IMD/BDR performance which is the primary
purpose of a roofing filter).

2.  Is the 5-pole 500 Hz better than the 8-pole 400 Hz?

3.  Is the 8-pole 250 Hz better than the 5-pole 200 Hz?
(academic to me since I don't feel either is necessary
...see comment above re TX key clicks, phase noise, etc).

The variable BW filters are interesting but
I would not consider them until we have some actual
results for IMD/BDR.  They are NOT providing ultimate
selectivity as they do in the case of the K2, which
seems to be confusing many folks.

73,  Bill  W4ZV

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[Elecraft] Price Comparison and Comment

2007-05-04 Thread Bill Tippett

W5EWA:
>but now someone says that we DON'T need them all.

Definitely not...unless we have more money than
sense.  You need only ONE per major mode, which will
cover the widest bandwidth you ever expect to use in
that mode.  For example:

CW - 500 or 400.  250 and 200 are definite overkill
IMHO and not necessary in addition to narrow DSP BWs.
The reason is that IMD/BDR spurious issues at <500 Hz
will be far overridden by other issues such as phase noise,
key clicks, etc that come from the transmitted signals.
There is no point in making a receiver many dB better
than the environment in which it must live!  No matter
how good a receiver is it cannot eliminate transmitter
defects (maybe Flex's SDR-X can but that remains to be
proven).

SSB - 2.7 kHz unless you want ESSB (not sure how high
that goes these days but IMHO we should be trying to
minimize communications bandwidths rather than playing
broadcast disc jockey (my personal opinion!).  Those
folks should go to 29 MHz FM if they want to do that.

AM - 6 kHz

FM - 15 kHz

In fact you may not need ANY filters beyond
the 2.7 kHz stock filter unless you expect to have lots
of very close spaced S9+30 dB signals on CW (e.g. huge
low-band pileups or in contests).  The 2.7k should be
perfectly adequate for nearly any situation on SSB,
although it wouldn't surprise me to see someone offer
1.8 kHz, mainly for contesters.

A roofing filter's purpose is simply to minimize
spurious artifacts from being created *inside* the RX
by external signals.  It does NOT create the ultimate
selectivity (which is determined by the DSP filter at
the 2nd IF).  Please read the last sentence again!
Here's a simple summary:


Antenna > roofing filter > DSP filter > ear.

...roofing filter prevents very strong signals from
creating spurious (i.e. *NOT REAL*) signals which
will then appear inside the DSP.

...DSP filters provide the ultimate selectivity (i.e.
separating the *REAL* signals from each other).


The number of poles (i.e. shape factor of the
filter) can affect IMD/BDR issues inside the RX.  For
this reason hopefully Elecraft will provide actual
IMD/BDR measurements with each option to help answer
the following questions:

1.  Is the optional 8-pole 2.8 kHz better than the
stock 5-pole 2.7 kHz (by "better" I mean resulting
in better IMD/BDR performance which is the primary
purpose of a roofing filter).

2.  Is the 5-pole 500 Hz better than the 8-pole 400 Hz?

3.  Is the 8-pole 250 Hz better than the 5-pole 200 Hz?
(academic to me since I don't feel either is necessary
...see comment above re TX key clicks, phase noise, etc).

The variable BW filters are interesting but
I would not consider them until we have some actual
results for IMD/BDR.  They are NOT providing ultimate
selectivity as they do in the case of the K2, which
seems to be confusing many folks.

73,  Bill  W4ZV




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Re: [Elecraft] Price Comparison and Comment

2007-05-04 Thread Stan Rife
Well then, I have finally got to know the skinny on this ceiling filter (er 
roofing) issue and I am totally confused (still). I thought I had a handle on 
it (order them all), but now someone says that we DON'T need them all. How do 
you know which ones you do need? And I have seen someone say that one (or all) 
of them will be tuneable. Can some (again please) lay this out in laymens terms 
for the ignorant, non savy (ME) of us. 
   
   
   
  Stan Rife
  W5EWA
  Houston, TX
  K2 S/N 4216
  

Lee Buller <[EMAIL PROTECTED]> wrote:
  Bill,

You are right. After thinking on this for more than 10 minutesI came to the 
same conclusion. A K3 can be had for 1800 dollars in modular kit form...with 
just 100 watts and no bells and whistles. The 2.7 roofing filter comes with the 
unit, so you would have a workable unit after building it.

So, the price comparison I put out last weekend was...well...wrong! Wrong on so 
many levels.

I did not understand roofing filters at time and considered them IF Filters. I 
was informed by very nice people that not all five filters would be needed. So, 
that was a bogus assumption on my part.

Also, I looked at the price from a full blown perspective. What I like about 
Elecraft is that you can put in the pieces when you can afford them. Not like 
other companies who do not offer that kind of flexibility.

So...sorry about the poor email

Lee Buller
"Making a mistake is not a problem...not learning from mistakes is a big 
problem. This is assuming the problem is not life or death"




In our day and age it seems that Common Sense is in short supply. If you don't 
have any Common Sense - get some Common Sense and use it. If you can't find any 
Common Sense, ask for help from somebody who has some Common Sense. Is Common 
Sense devine?
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RE: [Elecraft] Price Comparison and Comment

2007-05-04 Thread Brett gazdzinski
 
I ordered just the 10 watt kit and a 6Khz filter,
which will allow me to play a lot before I get the 100
watt amp and the atu.

I don't contest or DX, so its nice to not have to get
a lot of filters, and a 2nd receiver.

I do want the band scope though!

The soft entry makes it a bit better than having to
plunk down a truck load of cash

Brett
N2DTS


> -Original Message-
> From: [EMAIL PROTECTED] 
> [mailto:[EMAIL PROTECTED] On Behalf Of Lee Buller
> Sent: Friday, May 04, 2007 11:07 AM
> To: Bill Tippett; Elecraft Reflector
> Subject: Re: [Elecraft] Price Comparison and Comment
> 
> Bill,
> 
> You are right.  After thinking on this for more than 10 
> minutesI came to the same conclusion.  A K3 can be had 
> for 1800 dollars in modular kit form...with just 100 watts 
> and no bells and whistles.  The 2.7 roofing filter comes with 
> the unit, so you would have a workable unit after building it.
> 
> So, the price comparison I put out last weekend 
> was...well...wrong!  Wrong on so many levels.
> 
> I did not understand roofing filters at time and considered 
> them IF Filters.  I was informed by very nice people that not 
> all five filters would be needed.  So, that was a bogus 
> assumption on my part.
> 
> Also, I looked at the price from a full blown perspective.  
> What I like about Elecraft is that you can put in the pieces 
> when you can afford them.  Not like other companies who do 
> not offer that kind of flexibility.
> 
> So...sorry about the poor email
> 
> Lee Buller
> "Making a mistake is not a problem...not learning from 
> mistakes is a big problem.  This is assuming the problem is 
> not life or death"
> 

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Re: [Elecraft] Price Comparison and Comment

2007-05-04 Thread Larry Phipps
Good chart, Bill. I especially agree with some of your footnote 
statements. Being a casual DXer and contest dabbler, I ordered a K3/100 
with just the KXV3. I ordered the modular kit because I wanted to 
experience the new kit methodology, and become familiar with the boards 
and architecture in case I need to do future maintenance. I think a 
couple evenings of time spent with the manual will be well worth it.


I purposely did not make a deposit, so that my unit would fall in the 
second run. I did this in case there are any hardware revisions after 
the first run. I should be early in run 2, and I thought that if I 
waited for feedback from the 1st run guys before ordering, I wouldn't 
get it until 2008 ;-)


I also purposely didn't order any extra filters, as I suspect that the 
variable roofing filters will be out before my order is ready, and I may 
want to consider them for added flexibility (at least for CW). I totally 
agree about internal ATUs... don't like them for a number of reasons. I 
have one I home-brewed that I like anyway. I also don't need a second 
receiver at the moment. K3 allows me to have world class performance at 
a bargain basement price (relatively speaking), with only the features I 
need, but gives me expandability in case I need more options down the road.


Oh, and since I already own a Z90 panadapter, I'm covered on that front.

73,
Larry N8LP



Bill Tippett wrote:

K0WA wrote:
> I am sure many of you have done this alreadybut it is 
interesting to meand I thought I would share

>
>   1.  FTDX9000 Contest  $5699 (no extras)
>   2.  Orion II   $4395
>   3.  K3 $3436 (Includes 5 filters)
>   4.  FT2000D$3399
>   5  Omni VII $3050 (with two filters)
>   6  IC756PROIII$2999
>
>   No coupons were added or any reduction of price for this small 
study of price.

>
>   As I see if, you just save $330 from putting it together.  
HM.  That kind of makes he happy and sad.  I had the fun of 
building the K2...but that doesn't seem worth it to build a K3.  Of 
course, I could be (and usually am) wrong in my thinking here.


Be careful with comparisons like this!  It
depends very much on your K3 configuration, and it also
depends on how you value issues like the quality of the
Sub Receiver, etc.  The beauty of the K3 is that it can
be configured very economically depending on what your
needs are.  Elecraft has cleverly configured the K3 to
allow it to appeal to many different users:

1.  Budget minded DXers who need an exceptional RX.
Include the basic K3, no ATU, KXV3 (for RX antenna
input) plus 500 Hz filter equals $2149.  CW filter
depends on IMD/BDR measurements but most likely
the 500 Hz 5-pole will be entirely sufficient
based on my experience with Orion.  Build one
yourself for $1907.

2.  Budget minded contesters who need 2 for SO2R.
Twice the above for $4298 assembled or $3814 kitted.

3.  Those who need truly high performance Sub RX
for diversity or for use in very crowded conditions.
K3 + Sub RX + KXV3 + two 500 Hz filters for $2825
assembled or $2525 kitted.  IMHO this combination
cannot be duplicated by any of the above rigs due
to the quality of both K3 receivers (pending actual
IMD/BDR measurements of course).

4.  Those who want a truly high performance
panadapter/bandscope using the K3's IF output to
an outboard SDR (e.g. Softrock 40, Clifton Laboratories
Z90/91 Panadapter, etc.)  This gets tricky to price
but it's nowhere near the $10k range of a full
blown IC-7800 or FTDX9000.

I'm not a fan of ATUs but you can add it
to the above if necessary.  Thank you Elecraft
and Ten-Tec for not forcing me to pay for an ATU
if I don't feel I need it (ditto for the 20 and
6 kHz filters I never use in my Orion).

I simply wanted to offer a counterpoint view
to the pricing listed above.  I'm sure many others
would do things differently but I believe Elecraft
has been very clever in allowing us to configure
exactly what we need...and nothing more.

73,  Bill  W4ZV

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Re: [Elecraft] Price Comparison and Comment

2007-05-04 Thread Lee Buller
Bill,

You are right.  After thinking on this for more than 10 minutesI came to 
the same conclusion.  A K3 can be had for 1800 dollars in modular kit 
form...with just 100 watts and no bells and whistles.  The 2.7 roofing filter 
comes with the unit, so you would have a workable unit after building it.

So, the price comparison I put out last weekend was...well...wrong!  Wrong on 
so many levels.

I did not understand roofing filters at time and considered them IF Filters.  I 
was informed by very nice people that not all five filters would be needed.  
So, that was a bogus assumption on my part.

Also, I looked at the price from a full blown perspective.  What I like about 
Elecraft is that you can put in the pieces when you can afford them.  Not like 
other companies who do not offer that kind of flexibility.

So...sorry about the poor email

Lee Buller
"Making a mistake is not a problem...not learning from mistakes is a big 
problem.  This is assuming the problem is not life or death"


 

In our day and age it seems that Common Sense is in short supply.  If you don't 
have any Common Sense - get some Common Sense and use it.  If you can't find 
any Common Sense, ask for help from somebody who has some Common Sense.  Is 
Common Sense devine?
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[Elecraft] Price Comparison and Comment

2007-05-04 Thread Bill Tippett

K0WA wrote:
> I am sure many of you have done this alreadybut it is 
interesting to meand I thought I would share

>
>   1.  FTDX9000 Contest  $5699 (no extras)
>   2.  Orion II   $4395
>   3.  K3 $3436 (Includes 5 filters)
>   4.  FT2000D$3399
>   5  Omni VII $3050 (with two filters)
>   6  IC756PROIII$2999
>
>   No coupons were added or any reduction of price for this small 
study of price.

>
>   As I see if, you just save $330 from putting it 
together.  HM.  That kind of makes he happy and sad.  I had the 
fun of building the K2...but that doesn't seem worth it to build a 
K3.  Of course, I could be (and usually am) wrong in my thinking here.


Be careful with comparisons like this!  It
depends very much on your K3 configuration, and it also
depends on how you value issues like the quality of the
Sub Receiver, etc.  The beauty of the K3 is that it can
be configured very economically depending on what your
needs are.  Elecraft has cleverly configured the K3 to
allow it to appeal to many different users:

1.  Budget minded DXers who need an exceptional RX.
Include the basic K3, no ATU, KXV3 (for RX antenna
input) plus 500 Hz filter equals $2149.  CW filter
depends on IMD/BDR measurements but most likely
the 500 Hz 5-pole will be entirely sufficient
based on my experience with Orion.  Build one
yourself for $1907.

2.  Budget minded contesters who need 2 for SO2R.
Twice the above for $4298 assembled or $3814 kitted.

3.  Those who need truly high performance Sub RX
for diversity or for use in very crowded conditions.
K3 + Sub RX + KXV3 + two 500 Hz filters for $2825
assembled or $2525 kitted.  IMHO this combination
cannot be duplicated by any of the above rigs due
to the quality of both K3 receivers (pending actual
IMD/BDR measurements of course).

4.  Those who want a truly high performance
panadapter/bandscope using the K3's IF output to
an outboard SDR (e.g. Softrock 40, Clifton Laboratories
Z90/91 Panadapter, etc.)  This gets tricky to price
but it's nowhere near the $10k range of a full
blown IC-7800 or FTDX9000.

I'm not a fan of ATUs but you can add it
to the above if necessary.  Thank you Elecraft
and Ten-Tec for not forcing me to pay for an ATU
if I don't feel I need it (ditto for the 20 and
6 kHz filters I never use in my Orion).

I simply wanted to offer a counterpoint view
to the pricing listed above.  I'm sure many others
would do things differently but I believe Elecraft
has been very clever in allowing us to configure
exactly what we need...and nothing more.

73,  Bill  W4ZV

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Re: [Elecraft] Price Comparison and Comment

2007-05-04 Thread David Wilburn
The first time (some years ago) I looked at the K2 as a possible 
candidate for space on my desk, I ended up marking it off the list. 
When I added up the cost of the features I wanted installed, plus the 
requirement to build it (I'm not that fired up about building, but have 
enjoyed it more than I thought I would have, and I have re-learned quite 
a bit) I felt that it was not worth the cost.  It turns out I was wrong.


Fast forward a few years, and with the rig I did pick up, I find that 
what I am wanting to do, and what the rig are capable of doing are 
headed in two opposite directions.


As a result, I took another look at available rigs, including rigs other 
 than the big three.  As I read more and more about the K2 I found that 
it had the features that "I" was looking for, and it would help me get 
to the next level in skills and capability that I was looking for.


I do not believe the K2 is for everyone, and as the designers have 
stated, it was designed to meet specific goals and excel as a receiver. 
 As a result of them meeting their goals, it has become the standard by 
which all others are judged.  But as they have stated, it is a comprise. 
 It is our job, as informed consumers, to see if the compromises made 
(there are compromises in all rigs) meet what our goals and expectations 
are for the money we are spending.  In my case, the K2 has done that 
admirably as it exceeds the capabilities of many higher priced rigs, in 
the areas that I find valuable.


In the back of my mind, as I am finishing up the K2, I was considering 
what other rig I would like to have, that would round out the 
capabilities of my shack and radio experience.  It would fill in where 
compromises were made in the K2.  And along comes the K3.


When I looked at your price list, it appeared you were doing the same 
thing I did when I first looked at the K2.  Looking at the price alone. 
 For both rigs (K2 and K3), the capabilities of the rig, the skills it 
allows the user to develop, the support of the community, the amazing 
ability to give feedback to the designers for what we would like to see 
in their current and future rigs, and be part of the design process, is 
something that cannot be found anywhere else.  Those intangibles, do not 
appear on the price list, but they add immense value to Elecraft's 
product.  I was not fully aware of all of them when I purchased my K2, 
but I have come to treasure them.


I do not know when I will be able to afford the K3.  But I am very 
impressed with what I continue to hear and read about it.  I know that 
it exceeds all the requirements that I had for "rounding" out my station 
and that the "intangibles" will still be there once I save the money up.


Best of luck to you.

David Wilburn
[EMAIL PROTECTED]
K4DGW
K2 #5982


Lee Buller wrote:

I am sure many of you have done this alreadybut it is interesting to 
meand I thought I would share
   
  1.  FTDX9000 Contest  $5699 (no extras)
  2.  Orion II   $4395 
  3.  K3 $3436 (Includes 5 filters)

  4.  FT2000D$3399
  5  Omni VII $3050 (with two filters)
  6  IC756PROIII$2999
   
  No coupons were added or any reduction of price for this small study of price.
   
  As I see if, you just save $330 from putting it together.  HM.  That kind of makes he happy and sad.  I had the fun of building the K2...but that doesn't seem worth it to build a K3.  Of course, I could be (and usually am) wrong in my thinking here.
   
  Lee

  K0WA
   
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[Elecraft] Price Comparison and Comment

2007-04-28 Thread Lee Buller
I am sure many of you have done this alreadybut it is interesting to 
meand I thought I would share
   
  1.  FTDX9000 Contest  $5699 (no extras)
  2.  Orion II   $4395 
  3.  K3 $3436 (Includes 5 filters)
  4.  FT2000D$3399
  5  Omni VII $3050 (with two filters)
  6  IC756PROIII$2999
   
  No coupons were added or any reduction of price for this small study of price.
   
  As I see if, you just save $330 from putting it together.  HM.  That kind 
of makes he happy and sad.  I had the fun of building the K2...but that doesn't 
seem worth it to build a K3.  Of course, I could be (and usually am) wrong in 
my thinking here.
   
  Lee
  K0WA
   
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