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  1. hevans1944

    Fuse length and you! For your health!

    Gee, if you were born fifty years ago, I would be willing to bet that you would try to replace a blown home house fuse, the kind that screws into a lamp-type receptacle, with a genuine copper Lincoln penny just to get the lights back on. Many homes were destroyed by electrical fires occurring...
  2. hevans1944

    Articles- Slight Error

    You betchum, Red Ryder! You just try carving the Roman numeral "C" into granite with a chisel! No way I know of to make that "C" look good... well, laser or water-jet engraving maybe, but the Romans didn't have those handy.:rolleyes:
  3. hevans1944

    Video signal amplifier.

    Yes. Or you can go to this website and just plug and chug, remembering to divide joules by 3,600,000 to convert the answer (in joules) to kilowatt-hours. Answer is 58,800 J /3,600,000 J/kWh or about 0.0163 kWh.
  4. hevans1944

    Simple SW receiver on 3V?

    I don't know of any links for free schematics of FM tuner front ends, although IIRC some kit hi-fi receivers circa 1950s to 1960s were sold with pre-built FM tuners because DIY construction was so tricky. There may be schematics, probably for sale, not free, available for these front ends. If I...
  5. hevans1944

    Simple SW receiver on 3V?

    I envy your experience with RF circuits! When I was growing up and beginning my journey down the road to learning electronics, radio frequency circuits were both fascinating and fairly easy to "play" with using vacuum tubes. Of course I didn't understand the math and had only a fuzzy idea of how...
  6. hevans1944

    Articles- Slight Error

    Gee... must be the "dog days" of summer creeping into this forum...o_O
  7. hevans1944

    Simple SW receiver on 3V?

    Here is a link to a simple one-transistor short-wave superheterodyne receiver (shown below). Looks like it may work from two A-size dry cells. All you old timers out there, pining for a comeback of the All American Five Tube Superhet Radio, can be welcomed into the transistor world with this...
  8. hevans1944

    Simple SW receiver on 3V?

    I have owned this little Panasonic "pocket sized" AM-FM-FM Stereo superheterodyne receiver, as shown in the image below, for many years. It uses two AAA 1.5 V alkaline cells. Volume from the built-in loudspeaker is not very loud, but I would normally use it with a stereo headset. These radios...
  9. hevans1944

    Video signal amplifier.

    I agree the online editor here can be a little hard to cope with. It is especially intolerant of misplaced quote and un-quote bracket pairs, which can occur if you just clip and paste text. I usually just hold down the shift key and move the cursor over the text I want to quote, which will...
  10. hevans1944

    Video signal amplifier.

    Not so much worried about me or you being right, more worried about the people seeking help here, that they get it right. You know from your decades of electronics experience that there is always more than one way to solve a problem. Sometimes "good" solutions become the "gold standard" and are...
  11. hevans1944

    Video signal amplifier.

    Well, go ahead and try that, and please let us here on the Mothership know how it turned out. From my experience, messing with composite video is a very tricky business, what with dc restoration of the blanking level and knowing how to pass a 4MHz bandwidth video signal without distortion, and...
  12. hevans1944

    Pulse Width Modulation

    Okay. No more guessing. No more trying to pull information we need from this unresponsive poster. I have uploaded an image of my Crystal Ball, the one that I use to divine the intent and purpose of posters who cannot or will not provide the information we responders need... if we are to provide...
  13. hevans1944

    Video signal amplifier.

    Not a problem when you selectively quote fragments of my original text: This was not a comment about wire size, it was a comment about my doubts that 500 feet of two pairs of solid, shielded, 18 AWG twisted-pairs, could be easily wrapped around a six-inch diameter spool and easily fed out and...
  14. hevans1944

    What is wrong with my wireless circuit?

    Of course not. This was yet another "drive by" poster looking for a quick answer rather than a dialog.
  15. hevans1944

    Video signal amplifier.

    If I Google "E111272 (05-21513) 18 AWG SHIELDED" this web page of results comes up. This is less than useful. We need to know exactly what kind of wire you are trying to work with. If it is truly solid and not stranded, that is a huge problem because solid wire is not very flexible, it doesn't...
  16. hevans1944

    Video signal amplifier.

    Amplification along with some other "analog magic" to recover bandwidth lost in the cable could be useful, but 500 feet is a loong distance for raw NTSC analog video. Please take the time to research how an NTSC color signal is assembled. The 60μs
  17. hevans1944

    Video signal amplifier.

    I think maybe I or someone else here has alienated @HANKMARS, because he hasn't responded lately. He came here looking for a "simple" solution to his "problem" of how to send color video from a cheap "lipstick" camera down 500 feet of some unspecified cable using a 747 op-amp. What he got was a...
  18. hevans1944

    Kelvin Varley Divider with Analog Switches/Muxes

    Where are you from? Are you an expert in electrical metrology? What kind of calibration standards do you have on hand to verify the accuracy of your DIY Kelvin-Varley Divider network? Since the stages in a KVD are cascaded, resistance errors accumulate quickly. In the Air Force, we used...
  19. hevans1944

    Video signal amplifier.

    Indeed. And if anyone tries to explain it in any detail, they are accused of putting up a "Wall of Text." Perhaps this perception arises from the fact that @aurelZ has stated "Just to let you know ,i finished my high electronic school somewhere at the end of 1988." Some people believe that once...
  20. hevans1944

    Create controlled 50v pulse

    I wish we had. Maybe then someone besides DTRA would have bought one. This device was discovered in the 1990s by scientists at Sandia National Laboratories (SNL), Albuquerque, New Mexico. SNL is co-located on Kirtland Air Force Base, home of the Air Force Weapons Laboratory. I worked at the...
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