date:20120821

Re: [Elecraft] odds and ends...

2012-08-21 Thread Larry Phipps

Hi Don. I just received the digest version of your post. I don't recall 
ever having said that a 48kHz sampling rate will produce a 96kHz display 
span. All my postings and web site info states that the span will be 
roughly equal to the sampling rate (minus a tiny amount due to the 
rolloff of the anti-aliasing filter in the sound card). I saw Joe's 
comment copied in the same digest message, and it is not correct. I'm 
sure it was just a slip of the fingers. The confusion comes in that the 
displayed span is roughly equal to twice the sound card bandwidth... not 
twice the sound card sampling rate. The bandwidth of the card, of 
course, is roughly half the sampling rate if it is properly implemented.

73,
Larry N8LP



On 8/19/2012 11:51 PM, elecraft-requ...@mailman.qth.net wrote:
 From:elecraft-boun...@mailman.qth.net
 [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Don Wilhelm
 Sent: Sunday, August 19, 2012 9:54 PM
 To: WB4JFI
 Cc:elecraft@mailman.qth.net
 Subject: Re: [Elecraft] odds and ends...

 I don't know the advertized numbers, but Mr. Nyquist aside, there is a
 reason that two independent experts with panadapter displays (Joe Subich
 W4TV and Larry Phipps K8LP of LP-Pan fame) state that a soundcard with a
 48 kHz rate will produce a 96 kHz span on the pan display.

 I do not doubt Nyquist, but I think the treatment of the numbers are a bit
 different (factor of 2)  Could it be due to the two channels? I really don't
 know the answers and do not have the energy to investigate such things
 anymore, I just choose to trust the experts who deal with this I/Q stuff on
 a daily basis.  I guess my scientific curiosity has declined with advancing
 years - it is no longer enjoyable to argue on the basis of observations vs.
 theory to sort out the differences - that was fun mind games many years
 ago. but today it is no longer a challenge.

 73,
 Don W3FPR

__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Re: [Elecraft] 2.5mm 3conductor RX I/Q to 3.5mm 3conductor soundcard line input cable

2012-08-21 Thread Buck k4ia

I believe they have one - whether your store does or not is another 
issue.  I haven't found it locally.

Elecraft recommends a pigtail cable to reduce strain on the board. 
There are some for sale on the internet (from China) but buy at least 
two because they are not the best quality.

Maybe someone else can cite a dependable source.

Buck
k4ia
K3 # 101  KX3 #715

On 8/20/2012 8:44 AM, Jeff Herr wrote:
 This is a radio shack item?



 WW6L

 __
 Elecraft mailing list
 Home: http://mailman.qth.net/mailman/listinfo/elecraft
 Help: http://mailman.qth.net/mmfaq.htm
 Post: mailto:Elecraft@mailman.qth.net

 This list hosted by: http://www.qsl.net
 Please help support this email list: http://www.qsl.net/donate.html

__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Re: [Elecraft] KX3 NOMIC

2012-08-21 Thread Lance Collister, W7GJ

Hi Eric,

Many thanks for catching the typo on my web page!  I have corrected it now.

http://www.bigskyspaces.com/w7gj/KX3.htm

I hope the information is useful to others also.  VY 73, Lance

ThankOn 8/20/2012 8:03 AM, eric norris wrote:
 Lance, thanks very much for posting your design.  I had trouble ordering the 
 four-wire connector using your part number from DigiKey, but found it at part 
 number CP-35401SP-ND.  You might want to update your page.

 73,

 Eric WD6DBM


-- 
Lance Collister, W7GJ
(ex WA3GPL, WA1JXN, WA1JXN/C6A, ZF2OC/ZF8, E51SIX, 3D2LR, 5W0GJ)
P.O. Box 73
Frenchtown, MT   59834-0073
USA
TEL: (406) 626-5728
QTH: DN27ub
URL: http://www.bigskyspaces.com/w7gj
Windows Messenger: w...@hotmail.com
Skype: lanceW7GJ
2m DXCC #11/6m DXCC #815

Interested in 6m EME?  Ask me about subscribing to the Magic Band EME
email group, or just fill in the request box at the bottom of my web
page (above)!

__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

[Elecraft] K2 - Low MDS on 20 meters band and AGC threshold setting

2012-08-21 Thread Pedro Correia

Hi all,

I have been building my Elecraft K2 serial 7179 since July 2011, it works fine 
since day one and it has the KAT2, KIO2, KNB2, K160RX, KSB2 and the just 
installed KAF2.
I always notice that the my MDS readings whit the XG2 on 20 Meters band are 4 
dB lower, I can read -135dBm (pre-amp ON, AGC OFF, Filter 700Hz, KAF2 in out 
position) on 40 meters but can only read -131dBm on 20 meters in the same 
conditions. Is this usual, or should I start looking at something?
Another question is about AGC threshold setting, mine is at 3,55V. I get that 
value from adjusting R1 until I can barely ear any difference in noise between 
AGC ON and OFF whit 700Hz Filter on CW no antenna connected. It seems good to 
me, but in what way am I loosing for having a low value.

Any help or idea please.

73

 

Pedro CT7AEZ
_..._
  
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Re: [Elecraft] odds and ends...

2012-08-21 Thread Bill Conkling

Note that SignalLink is also MONO!

...bc nr4c 

Sent from my Verizon Wireless Droid

-Original message-
From: Jim Rhodes jimk...@gmail.com
To: Jeff Herr her...@comcast.net
Cc: elecraft@mailman.qth.net
Sent: Mon, Aug 20, 2012 03:16:52 GMT+00:00
Subject: Re: [Elecraft] odds and ends...

Many (most?) laptop sound inputs are mono inputs and you need 2 channels
for IQ work. My old Gateway laptop switches depending on what is plugged
into it but my newer Samsung only does mono.

Jim K0XU Sent from my Xoom tablet
On Aug 19, 2012 9:53 PM, Jeff Herr her...@comcast.net wrote:

 Can someone explain why an external interface product, signalink, rig
 blaster, etc is needed between a kx3 and a laptop?

 -Original Message-
 From: elecraft-boun...@mailman.qth.net
 [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of KQ8M
 Sent: Sunday, August 19, 2012 7:12 PM
 To: d...@w3fpr.com; 'WB4JFI'
 Cc: elecraft@mailman.qth.net
 Subject: Re: [Elecraft] odds and ends...

 Not really following this thread but I must have some really bad cards  
from
 creative, asus and m-audio as my 96KHz cards only get 96Khz total, 48KHz
 either side of center and my 192KHz cards only get 192KHz total, 96KHz
 either side of center using my K3, LP-Pan and PowerSDR. Or with any of my
 SDR receivers and CWSkimmer. Or with any SDR receivers I build and test
 with
 Rocky, HDSDR, WinSDR etc. I know of no known low cost sound card that will
 provide 384KHz of total audio bandwidth.

 73,
 Tim Herrick, KQ8M
 Charter Member North Coast Contesters
 k...@kq8m.com

 AR-Cluster V6 kq8m.no-ip.org
 User Ports: 23, 7373  with local skimmer, 7374 without local skimmer  
Server
 Ports: V6 3607, V4 Active 3605, V4 Passive 3606

 -Original Message-
 From: elecraft-boun...@mailman.qth.net
 [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Don Wilhelm
 Sent: Sunday, August 19, 2012 9:54 PM
 To: WB4JFI
 Cc: elecraft@mailman.qth.net
 Subject: Re: [Elecraft] odds and ends...

 I don't know the advertized numbers, but Mr. Nyquist aside, there is a
 reason that two independent experts with panadapter displays (Joe Subich
 W4TV and Larry Phipps K8LP of LP-Pan fame) state that a soundcard with a
 48 kHz rate will produce a 96 kHz span on the pan display.

 I do not doubt Nyquist, but I think the treatment of the numbers are a bit
 different (factor of 2)  Could it be due to the two channels? I really
 don't
 know the answers and do not have the energy to investigate such things
 anymore, I just choose to trust the experts who deal with this I/Q stuff  
on
 a daily basis.  I guess my scientific curiosity has declined with  
advancing
 years - it is no longer enjoyable to argue on the basis of observations  
vs.
 theory to sort out the differences - that was fun mind games many years
 ago. but today it is no longer a challenge.

 73,
 Don W3FPR

 On 8/19/2012 5:45 PM, WB4JFI wrote:
  Mr Nyquist would be happily surprised at that.  With IQ samples at
  48kS/s each, you get a maximum of 48kHz, or one-half the total
 bandwidth.  Not 48k+48k.

  So, with a 48k sample rate, you will get plus and minus 24k from center.

  Sent from tfox iPad

  On Aug 19, 2012, at 4:33 PM, Joe Subich, W4TV li...@subich.com
 wrote:

  The sound card's maximum sampling rate will determine how wide your
  panadapter display can be (in kHz); for example, a sound card
  capable of sampling at 48 kHz can display slightly less than 48 kHz
  of spectrum. If you want a wider display, you will have to ensure
  that your sound card can sample at higher rates.
  A sound card capable of 48 KHz sample rate can display slightly less
  than 96 KHz.  With I/Q inputs and 48 KHz sampling you get +/- 48 KHz.

  73,

  ... Joe, W4TV

  On 8/19/2012 4:20 PM, Richard Ferch wrote:
  Jeff,

  In addition to the cable, you will also need to be sure that your
  laptop's sound card accepts stereo input. Panadapter software
  requires stereo input (I and Q channels). Some laptop input jacks
  will only accept mono signals, even though the laptop's sound card
  itself is stereo. My newest laptop, for example, has a TRRS jack for
  the sound card with a single input line, two stereo output lines, and
 ground.
  I have no way to get stereo input into this sound card. An older
  laptop I have has separate input and output jacks, but while the
  output jack is stereo, the input jack is mono. If your laptop is
  like either of these, your only recourse may be to get an external
  USB sound card with stereo inputs.

  The sound card's maximum sampling rate will determine how wide your
  panadapter display can be (in kHz); for example, a sound card
  capable of sampling at 48 kHz can display slightly less than 48 kHz
  of spectrum. If you want a wider display, you will have to ensure
  that your sound card can sample at higher rates.

  Note that if you need to use an external (e.g. USB) sound card, it
  may or may not have 3.5mm inputs. For example, I have one with dual
  RCA phono jacks

Re: [Elecraft] odds and ends...

2012-08-21 Thread Joe Subich, W4TV


I don't know how Chen determines input overload - whether he's seeing
digital overrun in the data or measuring clipping in the audio input.
I suspect you are seeing the inevitable narrow range between hum/noise
on the audio output or the high noise floor of the particular sound
card and the limited signal handling capability (ca. 4.5V P-P) of a
single rail, 5V device.

However, unless a 24 bit soundcard is using +/- 12V supplies for the
analog input circuitry, there simply isn't 130 dB of usable range
between the noise floor and clipping levels.  A properly designed 16
bit sound card will produce in excess of 90 dB dynamic range if the
designer takes care with the noise floor issues.  That is sufficient
to handle signals from the receiver's noise floor to S9+20 dB with-
out AGC in most cases if the receiver itself linear.  For signals
above that level it will take some kind of AGC simply to keep levels
within the linear range of the receiver's front end/mixers.

73,

... Joe, W4TV


On 8/20/2012 8:58 AM, Bill Frantz wrote:
 Using a SignaLink USB interface, I often see cocoaModem
 reporting input overload from strong signals on 20 meters with
 the noise barely visible on the waterfall. This occurs with both
 the K3 and the Small Wonder Labs PSK-20 driving the system. (The
 Icom 706 MK2G generates a lot more noise.) I reduce the gain on
 the SignaLink, or with the K3 on the RF gain, but that pushes
 weak signals too low to decode.

 I am willing to accept that the SignaLink isn't a good sound
 card, but need evidence/alternatives.

 Cheers - Bill, AE6JV

 On 8/20/12 at 22:08, li...@subich.com (Joe Subich, W4TV) wrote:

 With real receivers you probably will never notice the difference in
 dynamic range between a 16 and 24 bit sound card.  The receiver AGC
 - even only modest AGC - will keep the dynamic range presented to the
 sound card well within anything the 16 bit sound card can handle.
 That is *unless* the 16 bit card is poorly designed with internal
 noise that wastes a significant part of the 16 bit range.

 Even without AGC, the range between background noise (the noise
 floor of the demodulation process including sky noise, thermal
 noise in the IF, etc.) and the clipping point of the audio output
 can be considerably less than 90 dB in real receivers.  Audio
 output levels tend to range from around 10 mV with no signal to
 just under 5V P-P (2V RMS) at best ... that's less than 50 dB.
 Even if one assumes the software can decode a 1 mV signal in the
 10 mV nose floor, the resulting dynamic range is still much less
 than 90 dB provided by a properly designed 16 bit sound card and
 unless the 24 bit soundcard uses other than the typical 5V power
 supply, its real performance will be limited by the same 5V P-P
 audio levels!

 Taken a step further - if the receiver produces a 1 mV noise floor
 with 24V P-P output (+/- 12V supplies), that's *still* less than
 90 dB of range.
 ---
 Bill Frantz| If the site is supported by  | Periwinkle
 (408)356-8506  | ads, you are the product.| 16345
 Englewood Ave
 www.pwpconsult.com |  | Los Gatos,
 CA 95032

 __
 Elecraft mailing list
 Home: http://mailman.qth.net/mailman/listinfo/elecraft
 Help: http://mailman.qth.net/mmfaq.htm
 Post: mailto:Elecraft@mailman.qth.net

 This list hosted by: http://www.qsl.net
 Please help support this email list: http://www.qsl.net/donate.html

__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

[Elecraft] KX3 laptop question (was odds and ends...)

2012-08-21 Thread Graham Kimbell G3TCT

If I want to use a small laptop with the KX3 to display the spectrum 
when out portable, does anyone have a suggestion for such small device 
with stereo input?  Preferably without a separate sound card.

Graham

On 19:59, Richard Ferch wrote:

 I have no way to get stereo input into this sound card. An older 
 laptop I have has separate input and output jacks, but while the 
 output jack is stereo, the input jack is mono. If your laptop is like 
 either of these, your only recourse may be to get an external USB 
 sound card with stereo inputs.

__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Re: [Elecraft] JUMA PA100 IMD

2012-08-21 Thread Jim Brown

On 8/20/2012 5:12 AM, Pete Meier wrote:
 some the rhetoric here recently about the JUMA PA100.  Some of it based on 
 supposition.

There was good reason for the supposition here -- there were no 
technical specs on the website.

73, Jim K9YC
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Re: [Elecraft] KAT500

2012-08-21 Thread ke9uw

Umm...
I want one of these but I have an MFJ998 which works well. One thing I like
is seeing the values that it selects for the L network. It seems to have an
almost reliable memory and tunes in a few seconds without a lot of clatter.
Probably the best MFJ item I have ever bought. OT, don't ask me about the 75
amp clean switching power supply that put birdies all up and down 75
meters. I enacted the no-questions-asked return policy on that.
I'll get the KAT500...any chance that it's possible to observe the tuner
values on VFO B on the K3...or the VGA display etc? That would be so nice.
I'm not asking if it's in the works, just if it can be done in future
programming by Elecraft. Any ideas?

Chuck, KE9UW



-
Chuck, KE9UW
--
View this message in context: 
http://elecraft.365791.n2.nabble.com/KAT500-tp7558017p7561347.html
Sent from the Elecraft mailing list archive at Nabble.com.
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Re: [Elecraft] K3 Suggestion - Remember Frequency per Band Mode

2012-08-21 Thread k1tm

I use both of these methods but in a slightly different way. Having come
from Icom rigs, I mapped the order of the band memories 0-9 to the same
layout that they use. I place the 60M memories in 10-14.

I have the 0-9 memories configured for band select, so I can retain the last
frequency used on the band for easy access. In addition, I use the memories
M1-M4, to divided up the bands into M1 for CW, M2 for PSK, M3 for SSB (extra
segment), M4 for SSB (general segment or a net frequency).

To make a big change in frequency or mode, I have several options:

1. Press MV, then Press 0 - 9 to go directly to the last used frequency and
mode on the desired band (I do this rarely)
2. Press MV, Rotate the main VFO knob to select the band and *then press
M1-M4 to select a new mode or spot on the band.*

This second option improves the ergonomics, as opposed to either the
sequence, reach across the radio and select the band, reach back across the
radio and press MV, select from M1-M4 and press, or Press MV, remember
which key from 0-9 takes you to the desired band and press it, followed by
press MV and then press M1-M4 for the desired mode and frequency range.

By rotating the dial, you get to choose the task completion to be either
enter, or MV, which leave you on the last frequency and mode for a given
band, or M1-M4 which allows you to select a mode and frequency range while
you are at it. I have switched completely to option 2, and rarely use the
band switch. In the end, to accomplish a large change in frequency and mode
it seems fastest to start with MV followed by rotation or simply M1-M4.

I no longer miss the band stacking registers.

--
View this message in context:
http://elecraft.365791.n2.nabble.com/K3-Suggestion-Remember-Frequency-per-Band-Mode-tp7560928p7561348.html
Sent from the Elecraft mailing list archive at Nabble.com.
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

1 2 >

1 - 100 of 109 matches

Mail list logo