I did a comparison between a 6558 and an LM833(low noise op amp) while I was repairing the power amp and installing a VLF Receiver in my Technics Stereo...
16202
Jack
wf0c
Sep 3, 2010 8:58 pm
Edgar did you get the vlf receiver instaled in your Technics? If so how did it work? Jack...
16203
EdgarBigDog
edgarbhmfa
Sep 4, 2010 12:00 am
Yes Sir, it's a definite "Go!" mission. The VLF receiver, with it's transformer-isolated input and computer line output, has absolutely no problem feeding from...
16204
Jack
wf0c
Sep 4, 2010 12:07 am
Good deal Edgar...I'll be looking for your post.. Jack...
16205
wellsia
Sep 7, 2010 5:38 pm
Hi all Wonder if anyone in this group has any experance with the Andrea RAK-7? I will be picking one up at the end of the month and I'm starting to collect all...
16206
Jogeir Lindseth
pete.flair
Sep 9, 2010 4:27 pm
Useful tool? http://www.vk2zay.net/article/51 To search for hum free locations. DU2/LA1NOA Jogeir [Non-text portions of this message have been removed]...
16207
Thomas D. Dean
tomdean@...
Sep 10, 2010 8:19 pm
Is this too far off topic? I set up a simple impedance measurement jig to apply to my loop. Spice Model in lieu of a schematic. Vs if from DDS chip. Rs is 1%....
16208
James
jimpat999
Sep 11, 2010 12:27 am
Current in a loop lags the voltage by 90 degrees. Jim...
16209
Thomas D. Dean
tomdean@...
Sep 11, 2010 12:44 am
... Assuming the resistance of the loop is negligible. My question was about the attempt to simulate the measurement with C code. I think I have something...
16210
EdgarBigDog
edgarbhmfa
Sep 11, 2010 1:53 am
The Mains Hum Probe would work much better if the Guy used an LM833 for his pre-amp and an LM386 as a speaker/headphone driver. The LM386 has an input...
16211
EdgarBigDog
edgarbhmfa
Sep 11, 2010 2:05 am
Hi Guys, I finally determined that free software would no longer work for uploading my DVD recordings to You Tube. A disabled vet should not have to spend ...
16212
VLF_Group@yahoogroups...
Sep 11, 2010 2:09 am
Hello, This email message is a notification to let you know that a file has been uploaded to the Files area of the VLF_Group group. File : /Edgar's...
16213
ninevictor
Sep 14, 2010 5:41 am
I own a Lear Siegler/Sierra model 127C req selective Voltmeter. Where can I find a functional description of the input plug. Its contacts are numerous and I...
16214
Manfred Kerckhoff
manfred_kerc...
Sep 14, 2010 8:08 am
Don, see message # 7517. Regards Manfred ... [Non-text portions of this message have been removed]...
16215
f6agr
Sep 14, 2010 8:12 am
To whom it might concern :o)) http://star.arm.ac.uk/jobs/2010/vlf_job_announcement.html Regards Jean-Louis Rault F6AGR IMO radio commission...
16216
ninevictor
Sep 14, 2010 5:05 pm
Manfred and David, Many thanks. That saved me some time and effort. I will be sure to post to the group if I learn anything else about this instrument worth...
16218
EdgarBigDog
edgarbhmfa
Sep 14, 2010 10:50 pm
Es war mit mir auch nicht gefunden! Edgar...
16219
Paul
paul@...
Sep 15, 2010 6:31 am
... The link worked yesterday but not today. Perhaps they were overloaded with applicants. -- Paul Nicholson --...
16220
Jean-L. RAULT
f6agr
Sep 15, 2010 11:26 am
Dear all See below the message I received from the Armagh observatory. Sorry for the inconvenience ... Jean-Louis Rault F6AGR " Dear Richard and Jean-Louis, ...
16221
EdgarBigDog
edgarbhmfa
Sep 17, 2010 12:16 am
I'm in love again. I have some LM4562's on order. Their noise rating is 2.7nv per (square-root of bandwidth) X gain, compared to the 4.5nv of my last...
16222
Thomas D. Dean
tomdean@...
Sep 17, 2010 1:42 am
... I am somewhat confused. The AD620 shows 9nv/sqrt(Hz) at a gain of 100, in the data sheet figure 10. If I compare this to the LM4562 at gain-100, the...
16223
EdgarBigDog
edgarbhmfa
Sep 17, 2010 3:07 am
I'm ADD and never was that good with math and electronic formulas, in general. Near as I can figure, the nanovolts value is multiplied by (square-root of ...
16224
Walter
karula4711
Sep 17, 2010 5:03 am
was searching for a replacement for the LF357 which is no longer available. Could be I now know. Thanks, Walter...
16225
bob
bob71741
Sep 17, 2010 11:16 pm
For a good discussion of calculating op amp noise please see the following: http://focus.ti.com/lit/an/sboa066a/sboa066a.pdf There is NO simple answer. The...
16226
Peter, 54N 10E
df3lp
Sep 19, 2010 5:38 pm
Hi. No, not a new myth about 19.6 kHz... Both 38 and 40.4 kHz synchronously show remarkable sudden steps in field strengths. See: ...
16227
Alan Melia
g3nyk
Sep 20, 2010 12:14 am
Hi Peter they are remarkable similar. Is there any other frequency being received on the same antenna?? I presume those two plots are with the same antenna. ...
16228
Peter, 54N 10E
df3lp
Sep 20, 2010 7:05 am
Hi Alan, ... Yes, same antenna(s), crossed loops. Here's the spectrogram from that dual channel receiver: http://www.df3lp.de/rdf/2010-09-18_wfl.png I can rule...
16229
Paul
paul@...
Sep 20, 2010 7:30 am
Here are charts for three days showing 38.0, 40.4, and for comparison, an intermediate empty channel at 39kHz. http://abelian.org/vlf/live/pws/2010-09-17.gif ...
16230
Walter
karula4711
Sep 20, 2010 6:32 pm
I think that's one transmitter on a couple of frequencies well apart. This is not uncommon. From your own chart ...
16231
Clive
ancient.flyer
Sep 20, 2010 6:52 pm
Sorry Walter, but I think that the 07:00 'transmissions' on 31.2 kHz, 46.8 kHz and 62.5 kHz are the 2nd, 3rd and 4th harmonics of a European standard PAL TV...
