Re: [Elecraft] Roofing filters and DSP bandwidth tuning

On 1/27/2021 3:06 PM, David Woolley wrote: Having the roofing filter too close to the DSP filter is not necessarily a good thing, as the roofing filters are likely to have worse passband ripples and will have non-linear phase responses, which can compromise digital modes.  At least some of the

Re: [Elecraft] Roofing filters and DSP bandwidth tuning

On 1/27/2021 2:48 PM, j...@kk9a.com wrote: I have both as well in all my radios. I can clearly hear the difference when switching between them. I mostly use the 250 Hz filter for CW and the 500 Hz filter for RTTY. Sorry, I mis-spoke. I have the 8-pole 250 Hz and 400 Hz filters, but I set the

Re: [Elecraft] Roofing filters and DSP bandwidth tuning

True.  Statement was focused on preventing AGC action from signals outside the DSP BW and to do that, you'd like the roofing filters to include the DSP BW but not much more.  The "effective" BW of the xtal filters is also something larger than the 2.5 kHz or 0.5 kHz or 0.25 kHz in the name ...

Re: [Elecraft] Roofing filters and DSP bandwidth tuning

On 27/01/2021 20:35, Fred Jensen wrote:   It follows that you'd probably like the selection of roofing filters to follow the DSP BW as closely as possible. Having the roofing filter too close to the DSP filter is not necessarily a good thing, as the roofing filters are likely to have worse

Re: [Elecraft] Roofing filters and DSP bandwidth tuning

I have 8 pole 400 Hz filters in my K3s's, not 500 Hz as well as 250 Hz. According to W0YK's presentation linked below the 400 filter has a bandwidth of 435 and the 250 filter has a bandwidth of 370. This data is for 8 pole crystal filters made by Inrad, I am not sure what filters Elecraft

Re: [Elecraft] Roofing filters and DSP bandwidth tuning

On 1/27/2021 12:14 PM, j...@kk9a.com wrote: FWIW, I have both the 400 and 250 8 pole filters. If money is an issue, I believe that there is very little bandwidth difference between the two. I have both as well in all my radios. I can clearly hear the difference when switching between them. I

Re: [Elecraft] Roofing filters and DSP bandwidth tuning

NJ Mike:  If I understand your question, the answer is "Yes, as you narrow the DSP BW with the 'WIDTH" knob, the roofing filters will switch such that the narrowest filter that still includes the DSP BW will be selected". To your second question, the ultimate BW is set by the DSP, and on my

Re: [Elecraft] Roofing filters and DSP bandwidth tuning

These are roofing filters, they do not effect how narrow the bandwidth can be adjusted. FWIW, I have both the 400 and 250 8 pole filters. If money is an issue, I believe that there is very little bandwidth difference between the two. John KK9A NJ Mike wrote: If I understand it

Re: [Elecraft] Roofing Filters

That explains it, thanks. John KK9A Sent via the Samsung Galaxy 7 edge, an AT 4G LTE smartphone. On Tue, Jun 18, 2019 at 1:12 PM Nr4c wrote: > The old 400Hz filter was a 8 pole variety. It’s been replaced by a new and > probably better 6 pole filter. As have several others. > > Sent from my

Re: [Elecraft] Roofing Filters

June 2019 18:04 To: Wayne Burdick Cc: Elecraft Reflector Subject: Re: [Elecraft] Roofing Filters So does Elecraft no longer sell this filter: http://www.inrad.net/product.php?productid=150=140 John KK9A Sent via the Samsung Galaxy 7 edge, an AT 4G LTE smartphone. On Tue, Jun 18, 2019 at 11:34 AM

Re: [Elecraft] Roofing Filters

The old 400Hz filter was a 8 pole variety. It’s been replaced by a new and probably better 6 pole filter. As have several others. Sent from my iPhone ...nr4c. bill > On Jun 18, 2019, at 12:04 PM, "j...@kk9a.com" wrote: > > So does Elecraft no longer sell this filter: >

Re: [Elecraft] Roofing Filters

So does Elecraft no longer sell this filter: http://www.inrad.net/product.php?productid=150=140 John KK9A Sent via the Samsung Galaxy 7 edge, an AT 4G LTE smartphone. On Tue, Jun 18, 2019 at 11:34 AM Wayne Burdick wrote: > The KFL3A is an 8-pole filter. > > The KFL3C is a 6-pole filter. In a

Re: [Elecraft] Roofing Filters

The KFL3A is an 8-pole filter. The KFL3C is a 6-pole filter. In a 400 Hz bandwidth, performance will be virtually indistinguishable from the 8-pole. 73, Wayne N6KR > On Jun 18, 2019, at 8:21 AM, j...@kk9a.com wrote: > > The new Elecraft site is a little vague regarding roofing filters so

Re: [Elecraft] Roofing Filters

Not very many, fortunately. Wayne N6KR > On Jun 22, 2017, at 6:01 PM, wrote: > > What percentage are rejected? > > FWIW, I have bought filters for other brand radios direct from Inrad for > decades however all of the filters in my K3S's were bought though

Re: [Elecraft] Roofing Filters

We actually test at higher levels than this. The hardware AGC is *after* the crystal filter. Gain control prior to the filter is in discrete steps under control of the user: preamps and attenuator sections. Wayne N6KR > On Jun 22, 2017, at 1:20 PM, Joe Subich, W4TV

Re: [Elecraft] Roofing Filters

> Could you elaborate on "dynamic range" in crystal filters? All crystals have imperfections (flaws). Those flaws create distortion when the crystal is driven with a high level signal and the distortion (non-linear response) results in intermodulation distortion (IMD). The K3/K3S

Re: [Elecraft] Roofing Filters

Hi Wayne, Could you elaborate on "dynamic range" in crystal filters? A quick search did not yield a definition. A SWAG might be another term for ultimate rejection or it with ripple in the passband... Just curious. 73, Bob K2TK ex KN2TKR (1956) & K2TKR On 6/22/2017 12:54

Re: [Elecraft] Roofing Filters

Get what you are saying but I go by what my Dad taught me... RE: Tools "Son, Buy the best tool you can find for each job. Save up if you have to. If you can't afford to buy the tool once, you surely can't afford to buy it twice." I apply that rule to tools, equipment, cabling, et al

Re: [Elecraft] Roofing Filters

Actually, it is just human nature to do that. For some, every penny counts. Mike va3mw On Thu, Jun 22, 2017 at 1:56 PM, Clay Autery wrote: > hence my earlier statement: > > "I'll be getting mine from Elecraft directly." > > Thousands of dollars in radio fear and people

Re: [Elecraft] Roofing Filters

hence my earlier statement: "I'll be getting mine from Elecraft directly." Thousands of dollars in radio fear and people risk niggling problems and time wasted over a few bucks... Just simply doesn't make sense to me. 73, __ Clay Autery, KY5G On 6/22/2017 11:54 AM, Wayne

Re: [Elecraft] Roofing Filters

Meaning ya get what ya pay for ... or "value added". (:-)) 73! K0PP On Jun 22, 2017 10:54, "Wayne Burdick" wrote: > Yes. We screen every INRAD filter. Those that don’t meet our dynamic range > targets are rejected. > > Wayne > N6KR > > > > On Jun 22, 2017, at 9:46 AM, Vic

Re: [Elecraft] Roofing Filters

Yes. We screen every INRAD filter. Those that don’t meet our dynamic range targets are rejected. Wayne N6KR > On Jun 22, 2017, at 9:46 AM, Vic Rosenthal wrote: > > I recall Wayne saying that Elecraft tested filters received from INRAD for > some specific performance

Re: [Elecraft] Roofing Filters

I recall Wayne saying that Elecraft tested filters received from INRAD for some specific performance characteristics. I don't remember the details. Vic 4X6GP > On 22 Jun 2017, at 17:14, Clay Autery wrote: > > INRAD makes Elecraft's filters as I understand it... > > I'll

Re: [Elecraft] Roofing Filters

Clay Autery <caut...@montac.com> > To: elecraft <elecraft@mailman.qth.net> > Sent: Thu, Jun 22, 2017 10:26 am > Subject: Re: [Elecraft] Roofing Filters > > INRAD makes Elecraft's filters as I understand it... > > I'll be getting mine from Elecraft directly. > > __

Re: [Elecraft] Roofing Filters

K2ULR KX3 #211 -Original Message- From: Clay Autery <caut...@montac.com> To: elecraft <elecraft@mailman.qth.net> Sent: Thu, Jun 22, 2017 10:26 am Subject: Re: [Elecraft] Roofing Filters INRAD makes Elecraft's filters as I understand it... I'll be getting mine

Re: [Elecraft] Roofing Filters

INRAD makes Elecraft's filters as I understand it... I'll be getting mine from Elecraft directly. __ Clay Autery, KY5G On 6/22/2017 8:10 AM, Mike Harris wrote: > Wandering the web I notice that INRAD are offering K3 Roofers somewhat > less than Elecraft prices. > > Regards,

Re: [Elecraft] Roofing Filters

OOPS. I looked a the build sheet again and see that I did get the 250 filter. I don't remember ordering it but I did. I also took off the top cover and the filter is properly annotated. 73, Tom - KQ5S On Tue, Mar 14, 2017 at 9:33 AM, Tom wrote: > Is there an easy way to

Re: [Elecraft] roofing filters

Is the 500hz filter turned ON in the CONFIG menu? Are the filter gain and offset set properly? 73, Ted W4NZ -Original Message- From: Elecraft [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Robert 'RC' Conley Sent: Monday, June 23, 2014 10:46 AM To: Elecraft@mailman.qth.net

Re: [Elecraft] Roofing Filters - An Empirical Test

You can mitigate that problem somewhat by listening to the DX on the wide sub and the pileup with the narrow main rx. If the split is (roughly) larger than the filter bandwidth difference, then loud, continuous callers in the pile don't bother the DX signal, only your ability to locate the weak

Re: [Elecraft] Roofing Filters - An Empirical Test

Actually, I switched to this method too, mainly because of QRQ mode. And I got a 400 Hz filter for the main rx. On 5/15/2014 8:27 AM, Rick Tavan N6XI wrote: You can mitigate that problem somewhat by listening to the DX on the wide sub and the pileup with the narrow main rx. If the split is

Re: [Elecraft] Roofing Filters - An Empirical Test

The January 2009 QST has a table list the IMD numbers with various filters. Quite informative. There's is no easy way to cut/paste the data into an email, unfortunately. 73, Scott, N9AA On 5/12/14 3:54 PM, Dauer, Edward wrote: I would be interested in knowing if anyone has done an empirical

Re: [Elecraft] Roofing Filters - An Empirical Test

It's quite simple. If you have a very strong interfering signal that falls inside the SSB filter passband (2.7 or 2.8 kHz), but outside an installed narrow filter, the hardware AGC will not get pumped. Lacking such a filter, a strong enough signal (typically S9+20 or higher) *will* activate

Re: [Elecraft] Roofing Filters - An Empirical Test

I should have pointed out that this effect is most noticeable with CW or narrow data modes, where there's a large difference in bandwidth between wide and narrow filters. In SSB mode, a somewhat narrower filter (say 1.8 kHz) will provide additional margin on an active band with strong signals,

Re: [Elecraft] Roofing Filters - An Empirical Test

My K3 was originally set up this way, 400 Hz in the main and 2.8 kHz in the sub. When working DX pileups with the main on the DX and the sub on the pileup, I definitely noticed the 'pumping' effect on the sub only. It was sometimes annoying when the DX was working a weak caller and the usual

Re: [Elecraft] ROOFING FILTERS CW PY5EG

Hi Oms, filter set up is described on page 45 and pages 53 54 of the owners manual, e.g. K3 Owners Manual D1.pdf: FLx BW, FLx FRQ, FLx GN, FLx ON and FLTX{md}. If you have done this correctly, then everything should be ok. If not, you may need to contact Elecraft. vy 73 de toby

Re: [Elecraft] ROOFING FILTERS CW PY5EG

What is the filter that you have configured for CW transmit? It must be the 2.7 or 2.8 kHz filter. 73, Don W3FPR py5eg wrote: Hi Folks: I installed, 2,1 1,8 1.0 and 0,4 roofing filters on my K3. It is working perfectly on SSB, but it is no working in the other modes i.e CW. Did I make

RE: [Elecraft] Roofing Filters

To: elecraft@mailman.qth.net Subject: Re: [Elecraft] Roofing Filters AnnLatz wrote: Can someone explain the meaning of roofing filters. I have searched everywhere and can't find a good explanation. Lisa recommended the FAQ section of Elecraft and there they just mention them. Maybe I should

Re: [Elecraft] Roofing Filters

You can check here... http://www.elecraft.com/K3/Roofing_Filters.htm 73, Ken K3IU AnnLatz wrote: Can someone explain the meaning of roofing filters. I have searched everywhere and can't find a good explaination. Lisa recommended the FAQ secftion of Elecraft and there they just mention

RE: [Elecraft] Roofing Filters

At 14:38:02 EST on Wed 20 Feb 2008 Alan Latz (KA9UCP) wrote . Can someone explain the meaning of roofing filters. I have searched everywhere and can't find a good explanation. Lisa recommended the FAQ section of Elecraft and there they just mention them. Maybe I should order an updated Ham

Re: [Elecraft] Roofing Filters

AnnLatz wrote: Can someone explain the meaning of roofing filters. I have searched everywhere and can't find a good explanation. Lisa recommended the FAQ section of Elecraft and there they just mention them. Maybe I should order an updated Ham bible from ARRL. Thanks, Alan KA9UCP

RE: [Elecraft] Roofing Filters

Can someone explain the meaning of roofing filters. I have searched everywhere and can't find a good explaination. Lisa recommended the FAQ secftion of Elecraft and there they just mention them. Maybe I should order an updated Ham bible from ARRL. The

RE: [Elecraft] Roofing Filters

First, thank you Ron for putting that in a very comprehensive manner that even I could understand ;-) As usual, you've turned on the light bulb. Now, when I purchased my K3 and debated on my purchase of the roofing filters, I spoke with a few hams who said that the roofing filters were primarily

Re: [Elecraft] Roofing Filters

But I wonder (always dangerous), if operating on some of the noisier bands, would there be a benefit to using a narrower filter to cut down on the amount of energy hitting the DSP in order to help with digging out weak signals? Or is that not a consideration with this particular implementation of

RE: [Elecraft] Roofing Filters

Hey Lyle, Thanks for the reply. Man, if anyone knows about how the K? DSP works... So if I read this right (bear with me, I'm learning), in keeping strong signals out of its passband, it will keep the hardware AGC from activating to eliminate pumping. And that makes perfect sense. Keeping the

RE: [Elecraft] Roofing Filters

, February 20, 2008 2:21 PM To: 'Ron D'Eau Claire'; elecraft@mailman.qth.net Subject: RE: [Elecraft] Roofing Filters First, thank you Ron for putting that in a very comprehensive manner that even I could understand ;-) As usual, you've turned on the light bulb. Now, when I purchased my K3 and debated

Re: [Elecraft] Roofing Filters

Hello Dave! So if I read this right (bear with me, I'm learning), in keeping strong signals out of its passband, it will keep the hardware AGC from activating to eliminate pumping... Correct. But, in the same scenario, if I had a 2.7khz filter and a 200hz filter with no strong signals, just

RE: [Elecraft] Roofing Filters

Thanks again Lyle, I believe I now have the proper prospective (looking at the block diagram of the K3 helped out too). So far in my limited operation of K3 #338, anytime I've tried to dig out a weaker CW signal next to a stronger one, the DSP filter has worked just fine. And I found when it was a

RE: [Elecraft] Roofing Filters

- [EMAIL PROTECTED] On Behalf Of Ron D'Eau Claire Sent: Wednesday, February 20, 2008 7:35 PM To: elecraft@mailman.qth.net Subject: RE: [Elecraft] Roofing Filters I see that Lyle (Mr. DSP) stepped in with the answer I couldn't have given you anyway G. That's the beauty of this reflector: lots

Re: [Elecraft] Roofing Filters

...Thanks again Lyle (hope I didn't bore too many on the list). Thank you for your interest in all this. Self-education is one of the pillars of our avocation, and it is always a pleasure to try to help in this process when I am able. 73, Lyle KK7P

Re: [Elecraft] Roofing Filters

Barry Simpson wrote: I am about to take the plunge and order a K3. Does it accommodate five roofing filters in addition to that supplied or is it limited to five in total ? 5 in total Barry. However the general coverage board is a separate board so does not take a slot. You can order up to

Re: [Elecraft] Roofing filters - on the other end

Hi Val, Purely from your description, operators' skills could be another factor. 73 Johnny Siu VR2XMC - Original Message - From: Val [EMAIL PROTECTED] To: Elecraft@mailman.qth.net Sent: Wednesday, May 09, 2007 9:37 PM Subject: [Elecraft] Roofing filters - on the other end While

Re: [Elecraft] Roofing filters - on the other end

Surely the best way to deal with this is to use the attenuator to improve the strong signal IMD performance, this applies to all radios, Analog and DSP based The BS7H CW Pileups were just dreadful. 73 Brendan EI6IZ On Wed, 2007-05-09 at 16:37 +0300, Val wrote: While the discussion on the

Re: [Elecraft] Roofing Filters

Zitat von Bill Tippett [EMAIL PROTECTED]: Filling K3 with filters as Toby suggested is both unnecessary and expensive IMHO. I think he is forgetting that there is very good DSP filtering in many lines removed Even a perfect receiver cannot prevent an adjacent TX signal's

Re: [Elecraft] Roofing Filters

Depends on what you want to do. I ordered the SSB 2.8KHz filter, plus the 250 and 400Hz for RTTY and CW contests. I'm not planning on any FM or AM use. I like having both 250 and 400 for RTTY - sometimes one or the other BW will copy better on my current rig depending on QRM, etc. I'm

Re: [Elecraft] Roofing Filters

How many roofing filters do you need in a K3? I belong to the liberal arts faction... In other words I don't know what I am talking about... ;-) I ordered my K3 with the secondary RX, 6kHz Filter, FM Filter, 2x 2.7kHz and the CG frontend filter. As for the other roofing filters, I also

Re: [Elecraft] Roofing Filters

mainly because we do not know yet, when which filters will be avaidable, and we do not have any hard data on the filters themselves. If no one else noticed, the web based order form has been updated, and there is a new roofing filter mentioned: KFL3A-1.0 1 kHz, 8-pole roofing filter

RE: [Elecraft] Roofing Filters

:36 PM To: Elecraft Reflector Subject: Re: [Elecraft] Roofing Filters How many roofing filters do you need in a K3? I belong to the liberal arts faction... In other words I don't know what I am talking about... ;-) I ordered my K3 with the secondary RX, 6kHz Filter, FM Filter, 2x 2.7kHz

Re: [Elecraft] Roofing Filters - Plots

Here is a link to our 8-pole, 8.215 MHz, crystal filter plots. It has now been added to the K3 page. http://www.elecraft.com/K3/K3_8_pole_plots.htm http://www.elecraft.com/news.htm Also note that we follow these filters with the DSP for even more out of band rejection and skirt steepness.

RE: [Elecraft] roofing filters - when to use them

How does the below compare to the K2? There are no roofing filters in the K2, right? In my homebrew receivers, I have a high Q tuned circuit at the antenna, then into the mixer, the output of the mixer goes to my filters (KIWA), then the IF chain. There is nothing to roof there, right? I get

Re: [Elecraft] roofing filters - when to use them

Brett, While there are DSP processors that *CAN* operate at higher frequencies (like the receiver 1st IF), they are very expensive - the downconversion to the DSP IF at 15 kHz is a much more economical approach. If you want to look at it that way, the filters in the K2 act both as a roofing

Re: [Elecraft] Roofing Filters, Data Modes, TXCO

On Apr 29, 2007, at 1:00 AM, Simon Brown (HB9DRV) wrote: Am I right in thinking that I can run the radio in SSB (data mode), engage the 6 kHz roofing filter and have about 5 kHz of flat(-ish) response? Yes. This being so I assume I need a 6 kHz roofing filter for the main *and* the sub

Re: [Elecraft] Roofing Filters, Data Modes, TXCO

- Original Message - From: wayne burdick [EMAIL PROTECTED] Yes. Thanks for the reply, don't you ever sleep? Anyway I have sent an order by email - it'll be my birthday present from me to me (50 years old in October, still got all my own hair and quite a few teeth). Simon 'ageing