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Files added
I've added a folder " Diode Commutation EMI" that explain the causes of diode commutation EMI and steps to mitigate it. There are other solutions today, special diodes with controlled turn off
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wn4isx <wn4isx@...>
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#99685
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understanding noise output in a mixer purely by datasheet
Hello , I am assembling the bits and peaces of what I learned and trying to implement them into my mixer shown in the link below. there is the -174+10log10(BW) of the component my mixer is 10GHZ so
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john23
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#99684
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Re: Some observations on linear power supplies
Microsemi became Microchips and changed the numbers on all their technical documents, I'm too busy tonight to find the correct paper. Basically when a diode is reverse biased and goes from conducting
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wn4isx <wn4isx@...>
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#99683
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Re: Some observations on linear power supplies
The only thing that made sense about Astron supplies is they sure made/make money. For overvoltage protection?I'd use something like the one shown in https://axotron.se/index_en.php?page=26 I'd place
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wn4isx <wn4isx@...>
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#99682
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Re: Some observations on linear power supplies
I've seen some stuff out there that puts a cap across rectifier diodes, sometimes just two out of the four, not sure why they'd do that. I also used to see a cap across the AC line, or a
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Roy J. Tellason, Sr.
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#99681
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Re: Some observations on linear power supplies
That crowbar circuit in the referenced pdf didn't make a whole lot of sense to me. Not that I examined it that closely, it's approaching the limit for what I can see on this monitor. But do you need
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Roy J. Tellason, Sr.
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#99680
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Re: Some observations on linear power supplies
I last messed with the 723 somewhere in the early 1970s. I'm guessing that this was before the common 3-terminal regulator parts were pretty much everywhere. I have very little reason to consider
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Roy J. Tellason, Sr.
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#99679
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Re: Some observations on linear power supplies
Note 3 should read Add a 0.01uF capacitor with a 27~33 ohm resistor in series across each power rectifier to minimize commutation EMI [radio noise]. I have a nice PDF on diode commutation noise and
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wn4isx <wn4isx@...>
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#99678
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Some observations on linear power supplies
First I consider Astron power supplies to be over rated and exist only because "hams have always used them." I'm amazed [really more dismayed] they get decent reviews. There are too many deficiencies
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wn4isx <wn4isx@...>
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#99677
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A "magic" antenna
When a member of our shortwave listener club showed me a PA0RDT active E-Probe antenna I almost giggled, being polite I didn't giggle. However I thought "Well PT Barnum was right...one is born every
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wn4isx <wn4isx@...>
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#99676
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Re: I found a stash of 5 'new old stock' 5CP1 5 inch oscilloscope CRT
Re: " Honda stock electrics sucked almost as bad as Lucas." I've never been able to understand the original stock Honda 350/360 charge system. It appeared to be a SCR that shorted out the V+ after a
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wn4isx <wn4isx@...>
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#99675
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Re: I found a stash of 5 'new old stock' 5CP1 5 inch oscilloscope CRT
An interesting read, that. I've been pretty lucky, the closest I've come to that kind of an encounter is the other end of the town where I lived before I moved over here. That, and one other occasion
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Roy J. Tellason, Sr.
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#99674
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Re: I found a stash of 5 'new old stock' 5CP1 5 inch oscilloscope CRT
I'm really a shortwave listener who happened to pick up his ham license. https://en.wikipedia.org/wiki/1974_Super_Outbreak That nightmare convinced me ham radio had a use. I rode a Honda CB350 with a
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wn4isx <wn4isx@...>
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#99673
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Re: I found a stash of 5 'new old stock' 5CP1 5 inch oscilloscope CRT
I remember seeing them mentioned a fair amount back when, not so much lately. I can believe that.
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Roy J. Tellason, Sr.
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#99672
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Re: I found a stash of 5 'new old stock' 5CP1 5 inch oscilloscope CRT
At one time 88mH (and other value) inductors were as common as roaches and just about as valuable. Today they are scarce, a quick net search didn't find any 'real' 88mH loading coils for sale. RTTY is
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wn4isx <wn4isx@...>
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#99671
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Re: I found a stash of 5 'new old stock' 5CP1 5 inch oscilloscope CRT
I've heard of those things for a really long time. Seen them referenced in magazines, etc. But I don't think that I've ever actually run across them... I do have some toroid coils, no idea what
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Roy J. Tellason, Sr.
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#99670
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Electronics Index
All sorts of stuff: https://mysite.du.edu/~etuttle/electron/elecindx.htm -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a
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Roy J. Tellason, Sr.
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#99669
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Re: I found a stash of 5 'new old stock' 5CP1 5 inch oscilloscope CRT
I have several software programs that emulate the old CRT mark/space vertical/horizontal? display with a simulation on the PC screen. It isn't as accurate as the CRT display, I'd say it's about 60%
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wn4isx <wn4isx@...>
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#99668
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Re: I found a stash of 5 'new old stock' 5CP1 5 inch oscilloscope CRT
Heh. I remember seeing a setup like that. This was so long ago that I can't even remember when it was. Somebody I knew thought that I might perhaps be interested in ham radio, and introduced me to
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Roy J. Tellason, Sr.
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#99667
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I found a stash of 5 'new old stock' 5CP1 5 inch oscilloscope CRT
I found a stash of 5 'new old stock' 5CP1 5 inch oscilloscope CRTs at my parent's home. The new owners called my sister and told her they found a box of "electrical junk" under the eves. I went over,
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wn4isx <wn4isx@...>
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#99666
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