开云体育

ctrl + shift + ? for shortcuts
© 2025 开云体育
Re: Active Antennas
Thank you wn4isx! Your link to Martin G8JNJ's active antenna pdf very extensive: https://qsl.net/l/lw7dfm/Antenas/Antena%20Mini%20Whip/MARTIN%20-%20G8JNJ%20- %20Active%20antennas.pdf More
By Bertho · #99886 ·
Re: Active Antennas
I found that one, https://www.pa3fwm.nl/projects/miniwhip/, but I have not found the second part one in the pictures that is discussed with improvements. I found this one that looks
By Bertho · #99885 ·
Re: Active Antennas
After spending too much time searching and reading about active antennas and building a library, I visited Amazon. Search for "Mini-Whip Antenna". There are enclosed ones, but I ordered a promising
By Bertho · #99884 ·
Re: Some comments on SDR radios and control software
Pieter-Tjerk de Boer, PA3FWM has a series of articles on E-Field antennas that can be extremely helpful in getting the best performance from these antennas. Fundamentals of the MiniWhip
By wn4isx <wn4isx@...> · #99883 ·
Re: Active Antennas
Pedid y recibiréis Simple and better circuit for MiniWhip antennas https://www.pa3fwm.nl/projects/miniwhip/ The 2SC5551A might be a viable substitute for the 2N5109 in the original PA0RDT
By wn4isx <wn4isx@...> · #99882 ·
Re: Some comments on SDR radios and control software
Thanks, I have no specific plans except testing the new technology and also look at GPS signals. I did a lot of work with GPS 30 years ago and I still have some active GPS antennas to try. The
By Bertho · #99881 ·
Active Antennas
Previously wn4isx posted a link to: https://www.pa3fwm.nl/projects/miniwhip/ The reference refers to an improved version but there is no link to it. Does anyone know where I can find the improved
By Bertho · #99880 ·
Re: Some comments on SDR radios and control software
What do you want to listen to? I might be able to offer some advice.
By wn4isx <wn4isx@...> · #99879 ·
Re: Sata acquisition and data logging
As I mentioned, I have one main program that was extremely expensive, cost me over $1000, I also routinely use Adobe Audition, while there are good audio programs for Linux like Audacity, they are not
By wn4isx <wn4isx@...> · #99878 ·
Re: Sata acquisition and data logging
Yes but I'd be forced to learn to use an Ardino, build a case, etc, the Dataq requies a USB cable and is ready to go, time saved at my age is well worth a few dollars.
By wn4isx <wn4isx@...> · #99877 ·
Re: Some comments on SDR radios and control software
Thanks for the introduction of SDRplay. I used to design commercial RF equipment but not for the last couple of decades. So I decided to buy the SDRply RSPdx-R2. Now I have to review the antenna
By Bertho · #99876 ·
Some comments on SDR radios and control software
OK I am not pushing the SDRplay line of SDR (software defined radios) but I received a PM that prompted this post. Oh I have no relationship with SDRplay then as a generally satisfied customer. I've
By wn4isx <wn4isx@...> · #99875 ·
Re: Sata acquisition and data logging
I've run nothing but linux since 1999. And yeah, virtualbox is one way to go, this email client is running under Slackware 12.2 (because I like the older version of kmail) on a Debian host system.
By Roy J. Tellason, Sr. · #99874 ·
Re: Sata acquisition and data logging
You can do a whole lot better than that, and way cheaper: https://www.nutsvolts.com/magazine/article/March2014_Davis -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest
By Roy J. Tellason, Sr. · #99873 ·
Re: Sata acquisition and data logging
I suspect the HP units had a wider Vin and higher "oops" Vin but the Dataqs work as advertised, the Dataq software is amazingly flexible and the $79 Dataqs are extremely stable. The Dataq software can
By wn4isx <wn4isx@...> · #99872 ·
Re: Slew rate and BW logic when designing differentietor of a pulse
* Faster op-amp. * An alternative differentiator that does not depend on an op-amp. Andy
By Andy · #99871 ·
Re: Sata acquisition and data logging
My first job working for HP as a Systems Engineer with Data ACQ hardware as my support product. I recall it being a large box with plugin boards for relays, thermo couples, digital ins and outs.
By Dan Kahn · #99870 ·
Sata acquisition and data logging
If you have projects that require data acquisition Ebay has several options but the gold standard would be Dataq. They offer a variety of data acquisition units, some are analog only, some feature
By wn4isx <wn4isx@...> · #99869 ·
Re: Slew rate and BW logic when designing differentietor of a pulse
Hello Andy ,I lowered the rise time to 5ns,As you can see in the attached photos. I have 437mV/14ns=31V/usec? which twice lower then?80 V/μs which described in the datasheet. How Can I improve the
By john23 · #99868 ·
Re: OFF-TOPIC: Jeeps, shifting, and snow (was: Batteries)
Nice story. My left knee was replace about 5 years ago and I can kneel. Some folks say that they can not. This Friday I'm getting a shot in my right knee. The last shot was 4 month ago, that's about
By Dan Kahn · #99867 ·