Elecraft roofing filters

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Elecraft roofing filters

ni0c
W4TV wrote:
"The difference between the 250 and 400 Hz filters is not
enough to be worthwhile (approximately 375 Hz vs. 430 Hz). "
 
Joe, what is your source for these numbers?  I've seen numbers
like this mentioned previously on the reflector.
 
I recently tested my K3 CW roofing filters using the XG-2 generator
at 7040 KHz (50 microvolts input) and KS7D's nice software package,
"K3 Filter Tools." 
 
Here's what I came up with, with AGC off and with the DSP
bandwidth set at least as wide as 900 Hz for all tests (to isolate
the effects of just the crystal roofing filter):
 
200 Hz, 5-pole: -6 dB BW = 210 Hz; -30 dB BW = 430 Hz
 
250 Hz, 8-pole: -6 dB BW = 260 Hz; -30 dB BW = 500 Hz
 
400 Hz, 8-pole: -6 dB BW = 380 Hz; -30 dB BW = 580 Hz
 
Note the uncertainty in each of the bandwidths above is
plus or minus 20 Hz, because I ran these sweeps in 10 Hz
increments to save time. (I'll repeat these tests using a
1 or 2 Hz increment, when I have some spare time.) 
 
These tests on my filters (as well as my experience by ear)
indicate there is an appreciable difference in the 250 and
400 Hz 8-pole filters.  I've always wondered, too, about
manufacturing tolerances on narrow crystal filters. 
 
73,
Chuck Guenther  NI0C
 
 
   


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Re: Elecraft roofing filters

Joe Subich, W4TV-4


> "The difference between the 250 and 400 Hz filters is not
> enough to be worthwhile (approximately 375 Hz vs. 430 Hz). "
>
> Joe, what is your source for these numbers?  I've seen numbers
> like this mentioned previously on the reflector.

My source is Elecraft: www.elecraft.com/K3/K3_8_pole_plots.htm

Look specifically at the last two plots which show:

           KFL3A-400      KFL3A-250
  -6 dB      435 Hz         370 Hz
 -60 dB      935 Hz         785 Hz
   SF        2.15:1         2.12:1  

INRAD do not publish the curves for the Elecraft (or Yaesu
8215 KHz) 250 Hz filter.  However, they do show the curve
for the 8830 KHz (Kenwood) version of the same filter and
it shows a similar percentage bandwidth (367.5/845 Hz at
-6/60dB).

> Here's what I came up with, with AGC off and with the DSP
> bandwidth set at least as wide as 900 Hz for all tests (to
> isolate the effects of just the crystal roofing filter):
>
> 200 Hz, 5-pole: -6 dB BW = 210 Hz; -30 dB BW = 430 Hz
>
> 250 Hz, 8-pole: -6 dB BW = 260 Hz; -30 dB BW = 500 Hz
>
> 400 Hz, 8-pole: -6 dB BW = 380 Hz; -30 dB BW = 580 Hz

Did you run those tests in a Data mode or with the CW pitch
set to 800 Hz?  If not, the low frequency skirts will be
sharpened significantly and the measured bandwidth will
less than the roofing filter.  With a CW pitch of 560 Hz
I measure 10% less bandwidth than in DATA (CF = 1500 Hz or
2210 Hz).  If I reduce the pitch to 300 Hz, the measured
bandwidth is further reduced (due to the DSP filter's low
frequency cut-off).

73,

   ... Joe, W4TV
 


> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of ni0c
> Sent: Thursday, February 05, 2009 3:47 PM
> To: [hidden email]
> Subject: [Elecraft] [K3] Elecraft roofing filters
>
>
> W4TV wrote:
> "The difference between the 250 and 400 Hz filters is not
> enough to be worthwhile (approximately 375 Hz vs. 430 Hz). "
>
> Joe, what is your source for these numbers?  I've seen numbers
> like this mentioned previously on the reflector.
>
> I recently tested my K3 CW roofing filters using the XG-2 generator
> at 7040 KHz (50 microvolts input) and KS7D's nice software package,
> "K3 Filter Tools."  
>
> Here's what I came up with, with AGC off and with the DSP
> bandwidth set at least as wide as 900 Hz for all tests (to isolate
> the effects of just the crystal roofing filter):
>
> 200 Hz, 5-pole: -6 dB BW = 210 Hz; -30 dB BW = 430 Hz
>
> 250 Hz, 8-pole: -6 dB BW = 260 Hz; -30 dB BW = 500 Hz
>
> 400 Hz, 8-pole: -6 dB BW = 380 Hz; -30 dB BW = 580 Hz
>
> Note the uncertainty in each of the bandwidths above is
> plus or minus 20 Hz, because I ran these sweeps in 10 Hz
> increments to save time. (I'll repeat these tests using a
> 1 or 2 Hz increment, when I have some spare time.)
>
> These tests on my filters (as well as my experience by ear)
> indicate there is an appreciable difference in the 250 and
> 400 Hz 8-pole filters.  I've always wondered, too, about
> manufacturing tolerances on narrow crystal filters.  
>
> 73,
> Chuck Guenther  NI0C
>
>
>    
>

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Re: Elecraft roofing filters

ni0c
W4TV wrote:


> My source is Elecraft: www.elecraft.com/K3/K3_8_pole_plots.htm
>
> Look specifically at the last two plots which show:
>
>            KFL3A-400      KFL3A-250
>   -6 dB      435 Hz         370 Hz
>  -60 dB      935 Hz         785 Hz
>    SF        2.15:1         2.12:1  
>
> INRAD do not publish the curves for the Elecraft (or Yaesu
> 8215 KHz) 250 Hz filter.  However, they do show the curve
> for the 8830 KHz (Kenwood) version of the same filter and
> it shows a similar percentage bandwidth (367.5/845 Hz at
> -6/60dB).
>

NI0C responds:

I'm still wondering what the tolerance is on such published curves.  

 

> Did you run those tests in a Data mode or with the CW pitch
> set to 800 Hz?  If not, the low frequency skirts will be
> sharpened significantly and the measured bandwidth will
> less than the roofing filter.  With a CW pitch of 560 Hz
> I measure 10% less bandwidth than in DATA (CF = 1500 Hz or
> 2210 Hz).  If I reduce the pitch to 300 Hz, the measured
> bandwidth is further reduced (due to the DSP filter's low
> frequency cut-off).
>
> 73,
>
>    ... Joe, W4TV

NI0C responds:

My testing was done in CW mode with the pitch in the
low 300's (320 Hz, as I recall).  So, when I repeat the tests,
I'll vary the pitch and see what happens, say 300 Hz, 600 hz,
and 800 Hz.  

73 & Thanks, Joe,  for your info!

Chuck Guenther NI0C



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Re: Elecraft roofing filters

Bill W4ZV

ni0c wrote
My testing was done in CW mode with the pitch in the
low 300's (320 Hz, as I recall).  So, when I repeat the tests,
I'll vary the pitch and see what happens, say 300 Hz, 600 hz,
and 800 Hz.
Another person who likes a low pitch!  This really affects what you will hear because the MCU firmware shifts the bandpass so that the low end always truncates at ~200 Hz.  If you use a nominal 500 Hz filter, this means it will be positioned from 200-700 Hz, so you'll hear signals 400 Hz above your zero beat frequency of 300.  This would be equivalent to an 800 Hz filter if centered.  The K3 operates differently from Orion which I know you had before.  This is exactly why I sold my 1000 Hz filter.  With a nominal bandwidth of 1100 Hz and 300 Hz PITCH, I was hearing signals 1 kHz above my zero beat QRG (i.e. my actual bandpass was 200-1300 Hz).  1 kHz above my QRG is not practical on any sort of crowded band.  If the band is not crowded with strong signals then the stock 2.7k filter is about as effective.

73,  Bill
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Re: Elecraft roofing filters

Joe Subich, W4TV-4
In reply to this post by ni0c


> I'm still wondering what the tolerance is on such published
> curves.

I would not be so much concerned about tolerance as sampling
error on the curves.  Still, the Elecraft curves are generally
similar to those given by INRAD for the same filter or those
with a similar (e.g., 8215 or 8830 KHz) center frequency and
bandwidth.  For example, Inrad's curves for the KFL3A-2.1K &
KFL3A-1.0 are identical to those from Elecraft ... Inrad's
curves are wider for the KFL3A-6K & KFL3A-400 and Elecraft's
cure is wider for the KFL3A-1.8K.  (Inrad does not publish
curves for the KFL3A-2.8K or KFL3A-250 ... nor do they have
any information on the 1500 and 500 Hz "custom" filters)

> My testing was done in CW mode with the pitch in the
> low 300's (320 Hz, as I recall).

The DSP begins to roll off at 200 Hz even if LO = 0.00.  Any
measurement where FC (Pitch) is less than [BW60/2 + 200] will
be inaccurate on the skirts and any measurement where FC is
less than BW6/2 + 200 will have essentially identical lower
frequency responses.

73,

   ... Joe, W4TV
   



> -----Original Message-----
> From: ni0c [mailto:[hidden email]]
> Sent: Thursday, February 05, 2009 5:42 PM
> To: [hidden email]; [hidden email]
> Subject: Re: [Elecraft] [K3] Elecraft roofing filters
>
>
> W4TV wrote:
>
>
> > My source is Elecraft: www.elecraft.com/K3/K3_8_pole_plots.htm
> >
> > Look specifically at the last two plots which show:
> >
> >            KFL3A-400      KFL3A-250
> >   -6 dB      435 Hz         370 Hz
> >  -60 dB      935 Hz         785 Hz
> >    SF        2.15:1         2.12:1  
> >
> > INRAD do not publish the curves for the Elecraft (or Yaesu
> > 8215 KHz) 250 Hz filter.  However, they do show the curve
> > for the 8830 KHz (Kenwood) version of the same filter and
> > it shows a similar percentage bandwidth (367.5/845 Hz at
> > -6/60dB).
> >
>
> NI0C responds:
>
> I'm still wondering what the tolerance is on such published curves.  
>
>  
> > Did you run those tests in a Data mode or with the CW pitch
> > set to 800 Hz?  If not, the low frequency skirts will be
> > sharpened significantly and the measured bandwidth will
> > less than the roofing filter.  With a CW pitch of 560 Hz
> > I measure 10% less bandwidth than in DATA (CF = 1500 Hz or
> > 2210 Hz).  If I reduce the pitch to 300 Hz, the measured
> > bandwidth is further reduced (due to the DSP filter's low
> > frequency cut-off).
> >
> > 73,
> >
> >    ... Joe, W4TV
>
> NI0C responds:
>
> My testing was done in CW mode with the pitch in the
> low 300's (320 Hz, as I recall).  So, when I repeat the tests,
> I'll vary the pitch and see what happens, say 300 Hz, 600 hz,
> and 800 Hz.  
>
> 73 & Thanks, Joe,  for your info!
>
> Chuck Guenther NI0C
>
>
>

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Re: Elecraft roofing filters

Guy, K2AV
In reply to this post by ni0c
Having used three different K3's equipped with 4 different sets of 250 & 400 hz 8 poles in overload city major contests, the usefulness of these filters is belied by the apparent closeness of numbers.
 
In practice we have found that associating the 400 with a DSP width of 450, and the "250" with a DSP width of 350 has been extremely useful, however "too close by the numbers" that may look on paper.
 
We use 450 for running for as long as it may last, and when the inevitable 30 over 9 crowder squeezes down on us, I reduce to 350 and if that isn't enough, *ADDITIONALLY* shift the center away 50 hz more. This combination plus the noise blanker for key clicks has worked extremely well. (Having 50 Hz granularity on the CW shift/widths would be *SO* useful here...)
 
I have measured the combined (roofing+DSP) drop on the steepest part of the skirts at ~12 db per 10 Hz with these two 8 pole filters. So bringing in the skirt "only" 30 or 40 Hz is enough to push down the crowder quite a bit, usually well out of hardware AGC, without narrowing the listening window to the point of missing QSO points and multipliers from all the inevitable off-frequency callers. 
 
Anyone who asks us what filters to buy for CW contesting, we tell them 400/250 8 pole set to 450/350.  Tried and true, not theory.
 
W4TV and I will just have to agree to disagree.
 
73, Guy.
----- Original Message -----
Sent: Thursday, February 05, 2009 4:47 PM
Subject: [Elecraft] [K3] Elecraft roofing filters

W4TV wrote:
"The difference between the 250 and 400 Hz filters is not
enough to be worthwhile (approximately 375 Hz vs. 430 Hz). "
 
Joe, what is your source for these numbers?  I've seen numbers
like this mentioned previously on the reflector.
 
I recently tested my K3 CW roofing filters using the XG-2 generator
at 7040 KHz (50 microvolts input) and KS7D's nice software package,
"K3 Filter Tools." 
 
Here's what I came up with, with AGC off and with the DSP
bandwidth set at least as wide as 900 Hz for all tests (to isolate
the effects of just the crystal roofing filter):
 
200 Hz, 5-pole: -6 dB BW = 210 Hz; -30 dB BW = 430 Hz
 
250 Hz, 8-pole: -6 dB BW = 260 Hz; -30 dB BW = 500 Hz
 
400 Hz, 8-pole: -6 dB BW = 380 Hz; -30 dB BW = 580 Hz
 
Note the uncertainty in each of the bandwidths above is
plus or minus 20 Hz, because I ran these sweeps in 10 Hz
increments to save time. (I'll repeat these tests using a
1 or 2 Hz increment, when I have some spare time.) 
 
These tests on my filters (as well as my experience by ear)
indicate there is an appreciable difference in the 250 and
400 Hz 8-pole filters.  I've always wondered, too, about
manufacturing tolerances on narrow crystal filters. 
 
73,
Chuck Guenther  NI0C
 
 
   


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Re: Elecraft roofing filters

Guy, K2AV
That's a wish for 10 Hz shift/width below, not 50 :)
----- Original Message -----
Sent: Tuesday, August 04, 2009 10:14 PM
Subject: Re: [Elecraft] [K3] Elecraft roofing filters

Having used three different K3's equipped with 4 different sets of 250 & 400 hz 8 poles in overload city major contests, the usefulness of these filters is belied by the apparent closeness of numbers.
 
In practice we have found that associating the 400 with a DSP width of 450, and the "250" with a DSP width of 350 has been extremely useful, however "too close by the numbers" that may look on paper.
 
We use 450 for running for as long as it may last, and when the inevitable 30 over 9 crowder squeezes down on us, I reduce to 350 and if that isn't enough, *ADDITIONALLY* shift the center away 50 hz more. This combination plus the noise blanker for key clicks has worked extremely well. (Having 50 Hz granularity on the CW shift/widths would be *SO* useful here...)
 
I have measured the combined (roofing+DSP) drop on the steepest part of the skirts at ~12 db per 10 Hz with these two 8 pole filters. So bringing in the skirt "only" 30 or 40 Hz is enough to push down the crowder quite a bit, usually well out of hardware AGC, without narrowing the listening window to the point of missing QSO points and multipliers from all the inevitable off-frequency callers. 
 
Anyone who asks us what filters to buy for CW contesting, we tell them 400/250 8 pole set to 450/350.  Tried and true, not theory.
 
W4TV and I will just have to agree to disagree.
 
73, Guy.
----- Original Message -----
Sent: Thursday, February 05, 2009 4:47 PM
Subject: [Elecraft] [K3] Elecraft roofing filters

W4TV wrote:
"The difference between the 250 and 400 Hz filters is not
enough to be worthwhile (approximately 375 Hz vs. 430 Hz). "
 
Joe, what is your source for these numbers?  I've seen numbers
like this mentioned previously on the reflector.
 
I recently tested my K3 CW roofing filters using the XG-2 generator
at 7040 KHz (50 microvolts input) and KS7D's nice software package,
"K3 Filter Tools." 
 
Here's what I came up with, with AGC off and with the DSP
bandwidth set at least as wide as 900 Hz for all tests (to isolate
the effects of just the crystal roofing filter):
 
200 Hz, 5-pole: -6 dB BW = 210 Hz; -30 dB BW = 430 Hz
 
250 Hz, 8-pole: -6 dB BW = 260 Hz; -30 dB BW = 500 Hz
 
400 Hz, 8-pole: -6 dB BW = 380 Hz; -30 dB BW = 580 Hz
 
Note the uncertainty in each of the bandwidths above is
plus or minus 20 Hz, because I ran these sweeps in 10 Hz
increments to save time. (I'll repeat these tests using a
1 or 2 Hz increment, when I have some spare time.) 
 
These tests on my filters (as well as my experience by ear)
indicate there is an appreciable difference in the 250 and
400 Hz 8-pole filters.  I've always wondered, too, about
manufacturing tolerances on narrow crystal filters. 
 
73,
Chuck Guenther  NI0C
 
 
   


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Re: Elecraft roofing filters

Joe Subich, W4TV-4
In reply to this post by Guy, K2AV

> Having used three different K3's equipped with 4 different
> sets of 250 & 400 hz 8 poles in overload city major contests,
> the usefulness of these filters is belied by the apparent
> closeness of numbers.

I'm happy that you are finding success with the 400/250 filter
pair but given the published specifications I suspect your
results have more to do with the DSP performance than the
actual width of the 250 Hz filter.

There is so little difference in the published curves for the
two filters (150 Hz at -60 dB) that roofing filter performance
alone can not be responsible for the differences performance
you describe.  If one is looking for improved "narrow CW"
performance, the 400/200 combination is a more effective and
cost efficient pairing.

> Anyone who asks us what filters to buy for CW contesting, we
> tell them 400/250 8 pole set to 450/350.  Tried and true, not
> theory.
>
> W4TV and I will just have to agree to disagree.

I don't think there is any disagreement ... unless you have
actually tried a 400/200 pair set to 450/250 and are trying
to say that the 250 Hz filter is tighter and suffers fewer
hardware AGC effects than the 200 Hz filter.  If you try to
make that point, there are several others including W4ZV,
who will disagree with you.

73,

   ... Joe, W4TV
 


> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of Guy
> Olinger, K2AV
> Sent: Tuesday, August 04, 2009 10:14 PM
> To: ni0c; [hidden email]
> Subject: Re: [Elecraft] [K3] Elecraft roofing filters
>
>
> Having used three different K3's equipped with 4 different
> sets of 250 & 400 hz 8 poles in overload city major contests,
> the usefulness of these filters is belied by the apparent
> closeness of numbers.
>
> In practice we have found that associating the 400 with a DSP
> width of 450, and the "250" with a DSP width of 350 has been
> extremely useful, however "too close by the numbers" that may
> look on paper.
>
> We use 450 for running for as long as it may last, and when
> the inevitable 30 over 9 crowder squeezes down on us, I
> reduce to 350 and if that isn't enough, *ADDITIONALLY* shift
> the center away 50 hz more. This combination plus the noise
> blanker for key clicks has worked extremely well. (Having 50
> Hz granularity on the CW shift/widths would be *SO* useful here...)
>
> I have measured the combined (roofing+DSP) drop on the
> steepest part of the skirts at ~12 db per 10 Hz with these
> two 8 pole filters. So bringing in the skirt "only" 30 or 40
> Hz is enough to push down the crowder quite a bit, usually
> well out of hardware AGC, without narrowing the listening
> window to the point of missing QSO points and multipliers
> from all the inevitable off-frequency callers.
>
> Anyone who asks us what filters to buy for CW contesting, we
> tell them 400/250 8 pole set to 450/350.  Tried and true, not theory.
>
> W4TV and I will just have to agree to disagree.
>
> 73, Guy.
> ----- Original Message -----
> From: ni0c
> To: [hidden email]
> Sent: Thursday, February 05, 2009 4:47 PM
> Subject: [Elecraft] [K3] Elecraft roofing filters
>
>
> W4TV wrote:
> "The difference between the 250 and 400 Hz filters is not
> enough to be worthwhile (approximately 375 Hz vs. 430 Hz). "
>
> Joe, what is your source for these numbers?  I've seen numbers
> like this mentioned previously on the reflector.
>
> I recently tested my K3 CW roofing filters using the XG-2 generator
> at 7040 KHz (50 microvolts input) and KS7D's nice software package,
> "K3 Filter Tools."  
>
> Here's what I came up with, with AGC off and with the DSP
> bandwidth set at least as wide as 900 Hz for all tests (to isolate
> the effects of just the crystal roofing filter):
>
> 200 Hz, 5-pole: -6 dB BW = 210 Hz; -30 dB BW = 430 Hz
>
> 250 Hz, 8-pole: -6 dB BW = 260 Hz; -30 dB BW = 500 Hz
>
> 400 Hz, 8-pole: -6 dB BW = 380 Hz; -30 dB BW = 580 Hz
>
> Note the uncertainty in each of the bandwidths above is
> plus or minus 20 Hz, because I ran these sweeps in 10 Hz
> increments to save time. (I'll repeat these tests using a
> 1 or 2 Hz increment, when I have some spare time.)
>
> These tests on my filters (as well as my experience by ear)
> indicate there is an appreciable difference in the 250 and
> 400 Hz 8-pole filters.  I've always wondered, too, about
> manufacturing tolerances on narrow crystal filters.  
>
> 73,
> Chuck Guenther  NI0C
>
>
>    
>
>
>
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>

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Re: Elecraft roofing filters

ni0c

Quoted discussion from K2AV and W4TV:

>
>
> > Anyone who asks us what filters to buy for CW contesting, we
> > tell them 400/250 8 pole set to 450/350.  Tried and true, not
> > theory.
> >
> > W4TV and I will just have to agree to disagree.
>
> I don't think there is any disagreement ... unless you have
> actually tried a 400/200 pair set to 450/250 and are trying
> to say that the 250 Hz filter is tighter and suffers fewer
> hardware AGC effects than the 200 Hz filter.  If you try to
> make that point, there are several others including W4ZV,
> who will disagree with you.
>
> 73,
>
>    ... Joe, W4TV
>  


The data I measured for the -30 dB down BW's of my 200
and 250 Hz filters supports what Joe says: 430 Hz  for the
200 Hz 5-pole versus 500 Hz for the 250 Hz 8-pole.

As a nearly 100% CW operator, I do like having three
CW roofing filters in my rig.  Matching DSP cutoff points
to the various filters is another variable to play with, and
thanks to Guy for the suggestions there.  

I do think there is a bit of a "truth in labeling" issue with
regard to narrow crystal filters that needs to be addressed
by the manufacturers.  Not everybody will remember, for
instance, that a 250 Hz filter may really have a bandwidth
of 375 Hz.  I recall a similar issue with a "125 Hz" filter that
I purchased for my TS-850S some years back.  The filter
curve supplied by the manufacturer showed it was actually
considerably wider than that (more than 200 Hz, as I recall).

I can understand the difficulty in manufacturing very high Q
multiple pole crystal filters, and that there might have been a
design goal in mind that wasn't met.  However, once we know
that the design goal wasn't met, shouldn't we revise our labelling
to more accurately reflect real world results?  

73,
Chuck Guenther  NI0C
K2/10  s/n 5853
K3/100 s/n 1061      
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Price promo on K3 at Dayton?

Jerry Flanders
In reply to this post by Guy, K2AV
You guys at Dayton - is there hamfest promo pricing on the K3 at Dayton?

Jerry W4UK

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Re: Price promo on K3 at Dayton?

Tom Hammond-2
Nope, but if you order at Dayton, for (slightly) delivery, there's no STATE TAX
(OR shipping, I think).

73,

Tom   N0SS

At 09:51 AM 5/15/2009, you wrote:

>You guys at Dayton - is there hamfest promo pricing on the K3 at Dayton?
>
>Jerry W4UK
>
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Re: Price promo on K3 at Dayton?

Adam Koczarski-2

I got in queue for the 2m option. No special pricing though, (I think).

Also heard Lyle talk about the K3 as an SDR. Basically what I heard at the
presentation he gave at his house last year.
Prior to Lyle's presentation there was a presentation about the Flex.
Differing philosophies were apparent. <Maybe> a few barbs back and forth. :)

Adam - K3ARK

>
> At 09:51 AM 5/15/2009, you wrote:
> >You guys at Dayton - is there hamfest promo pricing on the K3 at
> Dayton?
> >
> >Jerry W4UK
> >


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Re: Price promo on K3 at Dayton?

David Christ
Please summarize the differences in philosophy that you noticed.

David K0LUM

>"Adam Koczarski" wrote
>
>Also heard Lyle talk about the K3 as an SDR. Basically what I heard at the
>presentation he gave at his house last year.
>Prior to Lyle's presentation there was a presentation about the Flex.
>Differing philosophies were apparent. <Maybe> a few barbs back and forth. :)
>
>Adam - K3ARK
>
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Re: Price promo on K3 at Dayton?

dave.wilburn
http://n2.nabble.com/K3-or-SDR-5000--td457400.html

http://n2.nabble.com/SDR---K3---and-GUI-Interface-td447927.html

You can do all kinds of "flexible" searches here;
http://n2.nabble.com/Elecraft-f365791.html

Flexible, he he, too funny, I made a punny.

Dave Wilburn
NM4M

David Christ wrote:

> Please summarize the differences in philosophy that you noticed.
>
> David K0LUM
>
>> "Adam Koczarski" wrote
>>
>> Also heard Lyle talk about the K3 as an SDR. Basically what I heard at the
>> presentation he gave at his house last year.
>> Prior to Lyle's presentation there was a presentation about the Flex.
>> Differing philosophies were apparent. <Maybe> a few barbs back and forth. :)
>>
>> Adam - K3ARK
>>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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Re: Price promo on K3 at Dayton?

Matt Palmer-4
charging state tax, totally bogus IMHO, Hendricks was doing the same
thing, must be a california thing.


Matt
W8ESE
Former KD8DAO
http://blog.MattIsKichigai.com



On Fri, May 15, 2009 at 8:01 PM, David Wilburn <[hidden email]> wrote:

> http://n2.nabble.com/K3-or-SDR-5000--td457400.html
>
> http://n2.nabble.com/SDR---K3---and-GUI-Interface-td447927.html
>
> You can do all kinds of "flexible" searches here;
> http://n2.nabble.com/Elecraft-f365791.html
>
> Flexible, he he, too funny, I made a punny.
>
> Dave Wilburn
> NM4M
>
> David Christ wrote:
>> Please summarize the differences in philosophy that you noticed.
>>
>> David K0LUM
>>
>>> "Adam Koczarski" wrote
>>>
>>> Also heard Lyle talk about the K3 as an SDR. Basically what I heard at the
>>> presentation he gave at his house last year.
>>> Prior to Lyle's presentation there was a presentation about the Flex.
>>> Differing philosophies were apparent. <Maybe> a few barbs back and forth. :)
>>>
>>> Adam - K3ARK
>>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
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>> Please help support this email list: http://www.qsl.net/donate.html
>>
> ______________________________________________________________
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>
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Re: Price promo on K3 at Dayton?

Sid K3SX
I worked for a Maryland retailer at the Hamvention in the past and
opinion has nothing to do with it. If you don't get an Ohio merchant's
tax license and collect the tax they [the government] will prosecute you.

Matt Palmer wrote:

> charging state tax, totally bogus IMHO, Hendricks was doing the same
> thing, must be a california thing.
>
>
> Matt
> W8ESE
> Former KD8DAO
> http://blog.MattIsKichigai.com
>
>
>
> On Fri, May 15, 2009 at 8:01 PM, David Wilburn <[hidden email]> wrote:
>> http://n2.nabble.com/K3-or-SDR-5000--td457400.html
>>
>> http://n2.nabble.com/SDR---K3---and-GUI-Interface-td447927.html
>>
>> You can do all kinds of "flexible" searches here;
>> http://n2.nabble.com/Elecraft-f365791.html
>>
>> Flexible, he he, too funny, I made a punny.
>>
>> Dave Wilburn
>> NM4M
>>
>> David Christ wrote:
>>> Please summarize the differences in philosophy that you noticed.
>>>
>>> David K0LUM
>>>
>>>> "Adam Koczarski" wrote
>>>>
>>>> Also heard Lyle talk about the K3 as an SDR. Basically what I heard at the
>>>> presentation he gave at his house last year.
>>>> Prior to Lyle's presentation there was a presentation about the Flex.
>>>> Differing philosophies were apparent. <Maybe> a few barbs back and forth. :)
>>>>
>>>> Adam - K3ARK
>>>>
>>> ______________________________________________________________
>>> Elecraft mailing list
>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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>>>
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>>> Please help support this email list: http://www.qsl.net/donate.html
>>>
>> ______________________________________________________________
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Re: Price promo on K3 at Dayton?

w7aqk
In reply to this post by Matt Palmer-4
Hi All,

It may seem a tad late to respond to this email, but after Dayton I had
several hundred emails to sort my way through.

As a former practicing CPA, I can, perhaps, give a little perspective on the
sales tax issue.  First of all, it is not "bogus" for you to be charged
sales tax for the state where you are physically present in at the time you
consumate a transaction, assuming you take immediately delivery.  That's the
law, and it's the law nationwide.  So, a California dealer, selling
temporarily in Ohio, must charge Ohio tax on sales made, in person, in Ohio.

The reason we don't pay sales tax on many phone or internet orders is that
such sales are technically "interstate commerce".  If you are not resident
in the state where the sale is being actually made via telephone or internet
(or mail), and if it is being shipped to you in another state, no sales tax
should typically apply.  That is based on a long standing Supreme Court
decision.  However, if you purchase from a dealer in another state, and that
dealer also has operations in your state, you must pay the state tax for
your state.  That's why I can't order from HRO tax free, even by phone,
since they have a store in Phoenix.  AES, on the other hand, has no
operations in Arizona, so I can buy from them tax free.  I can go personally
to the HRO store in Portland, Oregon, however, and buy tax free from them,
but that's because I'm physically in Oregon, so no interstate commerce is
involved.  Oregon, by the way, doesn't have a sales tax, otherwise I would
have to pay an Oregon sales tax.  But I can't call the Portland store and
order something to be shipped to Arizona without paying Arizona's tax,
because HRO has a store in Arizona.

Sales tax laws, although seemingly similar from state to state, are not.  In
some states the tax is imposed on the seller (but they are generally allowed
to pass it on as a "surcharge" to the buyer), while in other states the tax
is technically imposed on the buyer, and collected by the seller.  But that
is only a technical distinction, and doesn't really affect the end result to
the consumer.  However, you can't blame Elecraft, or Hendricks, or any other
seller at Dayton for charging you Ohio tax on a sale, since they risk not
only being assessed the tax by Ohio, even if they don't collect it from you,
but they also risk large penalties for failing to charge tax!  Some states
are much more aggressive about monitoring special events like hamfests,
etc., and I strongly suspect something as big as Dayton does get attention
from the Ohio sales tax people.  So, although you may not like being charged
the tax, you can't reasonably expect the dealer to accept the risk of
possibly having to pay it for you!  If you don't want to pay it, see if the
dealer will handle it like a phone order and ship it to your address.  That
probably avoids the sales tax, but introduces shipping cost.  I say
"probably" because some states may have invoked rules saying that if the
sale is consumated in person, in their state, they are still entitled to the
tax, even if it is shipped out of state.  I'm not sure that stands up under
the Supreme Court ruling, but it has a point.  Very few states are more
aggressive about sales tax enforcement than California, by the way.  Bigger
states put more money into enforcement, so Ohio may also be a tough state.

Something you may not be aware of is that, even if you do order something
from out of state, and avoid the sales tax, you still may be liable for it
in your own state.  That's because almost all state laws are actually two
taxes--a "sales" tax, and a "use" tax.  If the sales tax doesn't apply for
some reason (like when it is sold to a dealer for resale, or no tax is paid
because the buyer produces an exemption certificate), there is still a "use"
tax (typically equal to what the sales tax would have been) if you use or
consume the product in that particular state.  This is typically applied to
businesses, but it technically applies to everyone.  So, if you live in
California, for example, and buy something by mail from Ohio (paying no
sales tax), California can technically assess you a use tax since you "use
or consume" the product in that state.  Fortunately, this is rarely
applied/enforced to individuals mainly because it is so hard to apply that
rule and enforce it.

I know that's more than you ever wanted to know about sales tax, but the
point is that you shouldn't get upset with a dealer like Elecraft who
charges you sales tax (unless they charge it improperly).  It's too big a
risk for that dealer to do otherwise.  Unfortunately, sales tax laws are
very complex, and if we understood them better, we wouldn't be so inclined
to get upset (with the dealer) about paying it.  In effect, you are
"shooting the messenger" if you get upset with the dealer.  Your argument is
really with the state!

Dave W7AQK




----- Original Message -----
From: "Matt Palmer" <[hidden email]>
To: "David Wilburn" <[hidden email]>
Cc: "Elecraft Discussion List" <[hidden email]>
Sent: Saturday, May 16, 2009 6:48 AM
Subject: Re: [Elecraft] Price promo on K3 at Dayton?


> charging state tax, totally bogus IMHO, Hendricks was doing the same
> thing, must be a california thing.
>
>
> Matt
> W8ESE
> Former KD8DAO
> http://blog.MattIsKichigai.com
>
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Re: Price promo on K3 at Dayton?

M0XDF
And I thought our VAT was complicated!
73 de M0XDF, K3 #174
--  
God could not be everywhere, and therefore he created mothers.
-Jewish proverb

On 22 May 2009, at 14:03, David Y. wrote:

> Hi All,
>
> It may seem a tad late to respond to this email, but after Dayton I  
> had
> several hundred emails to sort my way through.

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