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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 how long they last. After the shot it's like no problem at all. Can't complain at almost 85. Dan Kahn On Wednesday, March 5, 2025 at 08:57:21 PM EST, wn4isx via groups.io <wn4isx@...> wrote: At my last job the tractor of a tractor trailer was blocking our loading dock. The driver got into an argement with his dispatcher, left the keys on the seat and stomped off in a huff. No one but me had ever driven a vehicle without a synchromesh transmission and couldn't move the rig. I had the division manager write a nice letter with the agency assuming all liability before I moved it out of the way. It took a few false tries but I managed to move it a 100 feet onto the grass.? The company that owned the truck was beyond upset that someone without a CDL dared touch their precious truck and even more upset I'd parked it in the grass where the front wheels sank about 8 inches. ? Our first car was a 1969 VW bug and I kept trying to double clutch the poor thing. It was the worst snow Lexington has ever seen and a friend loaned me the car so I could get home. The advantage to learning to drive a clutch car on snow/ice covered roads was, once I learned to not double clutch, if I let the clutch out too fast the rear wheels broke free just like every other idiot on the road. It was 11 miles to home and by the time I got there, an hour, I was pretty good at shifting. ? That was the winter of 1977~78. I hope to never experience a winter like that again. We had 20 foot snow drifts in Fayette County. The next day after I got home I rigged a sled and we walked a mile to a grocery store to load up on supplies. A VW will go through almost anything, but 2 feet of snow lifts the car off the ground and it's no go time. By the time we made it to the store and home again, and took long hot showers and curled up together in our joined sleeping bags we were beyond beat. We'd just gotten a kitten who joined us. ? This last winter sucked because we got 5 or 6 inches of snow, then a half inch of rain that converted the top inch of snow to hard ice, then another 4 or 5 inches of snow. Our landlords spent 4 hours digging the top layer of snow and ice off, I used a broom to remove the bottom layer of snow, but we were too tired to go anywhere. Fortunately my wife learned a hard lesson back in 1978, keep enough food on hand. There are times I catch her looking in the pantry with an odd satisfied look on her face. ? ? This year she was out of the fun, had total right knee replacement on January 31, so walking in snow wasn't an option. ? Trust me, when you wear your knee out and it's time to replace it, go for it, yea it hurts, PT is a cast iron !@#$* but it will be well worth it. I had both of mine done last summer and there is now way I could have helped with the drive if I had my original knees. ? And it is snowing again. I'm so sick of the white stuff I could scream. I think I'll go to bed instead. ? About the jeep, unless you lived fairly close, it would have cost a fortune to move, and transferring ownership from someone in Kentucky to your state would have been a nightmare. There were several times when I was ready to send it to the crushers because of the legal nonsense. I lucked out, my younger sister saved all of Daddy's important papers and she had the original bill of sale and shipping order and we had photos from "Way back when." After a few hours of talking with the Sheriff, a state police detective, a motor vehicle enforcement officer and the county clerk everyone agreed the jeep wasn't stolen and there was no back tax because it had never been registered to begin with. What a PITA. NCIC had no record of the serial number, which was a bit of a hassle.? ? I wish the new owner success with the jeep and hope he has it ready for the Independence Day Parade here. I included a stripped R392/URR and the mating T-195 transmitter with jeep mounting platform. The T-195 was complete but I removed and destroyed the dynamotor. [like I need 1000V at 100mA] There's no way the T-195 would meet any modern transmitter specification and the high voltage could be lethal. It looks complete so the new owner is happy, although the R392/T-195 were really Korean conflict era comm gear. I tossed in some late WWII era "walkie talkies" and field phones. I pulled the crystal from the walkie talkie transmitter. No sense having someone come up around 50 MHz and get in trouble. ? ? |
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Re: OFF-TOPIC: Jeeps, shifting, and snow (was: Batteries)
wn4isx
At my last job the tractor of a tractor trailer was blocking our loading dock. The driver got into an argement with his dispatcher, left the keys on the seat and stomped off in a huff. No one but me had ever driven a vehicle without a synchromesh transmission and couldn't move the rig. I had the division manager write a nice letter with the agency assuming all liability before I moved it out of the way. It took a few false tries but I managed to move it a 100 feet onto the grass.?
The company that owned the truck was beyond upset that someone without a CDL dared touch their precious truck and even more upset I'd parked it in the grass where the front wheels sank about 8 inches.
?
Our first car was a 1969 VW bug and I kept trying to double clutch the poor thing. It was the worst snow Lexington has ever seen and a friend loaned me the car so I could get home. The advantage to learning to drive a clutch car on snow/ice covered roads was, once I learned to not double clutch, if I let the clutch out too fast the rear wheels broke free just like every other idiot on the road. It was 11 miles to home and by the time I got there, an hour, I was pretty good at shifting.
?
That was the winter of 1977~78. I hope to never experience a winter like that again. We had 20 foot snow drifts in Fayette County. The next day after I got home I rigged a sled and we walked a mile to a grocery store to load up on supplies. A VW will go through almost anything, but 2 feet of snow lifts the car off the ground and it's no go time. By the time we made it to the store and home again, and took long hot showers and curled up together in our joined sleeping bags we were beyond beat. We'd just gotten a kitten who joined us.
?
This last winter sucked because we got 5 or 6 inches of snow, then a half inch of rain that converted the top inch of snow to hard ice, then another 4 or 5 inches of snow. Our landlords spent 4 hours digging the top layer of snow and ice off, I used a broom to remove the bottom layer of snow, but we were too tired to go anywhere. Fortunately my wife learned a hard lesson back in 1978, keep enough food on hand. There are times I catch her looking in the pantry with an odd satisfied look on her face.
?
?
This year she was out of the fun, had total right knee replacement on January 31, so walking in snow wasn't an option.
?
Trust me, when you wear your knee out and it's time to replace it, go for it, yea it hurts, PT is a cast iron !@#$* but it will be well worth it. I had both of mine done last summer and there is now way I could have helped with the drive if I had my original knees.
?
And it is snowing again. I'm so sick of the white stuff I could scream. I think I'll go to bed instead.
?
About the jeep, unless you lived fairly close, it would have cost a fortune to move, and transferring ownership from someone in Kentucky to your state would have been a nightmare. There were several times when I was ready to send it to the crushers because of the legal nonsense. I lucked out, my younger sister saved all of Daddy's important papers and she had the original bill of sale and shipping order and we had photos from "Way back when." After a few hours of talking with the Sheriff, a state police detective, a motor vehicle enforcement officer and the county clerk everyone agreed the jeep wasn't stolen and there was no back tax because it had never been registered to begin with. What a PITA.
NCIC had no record of the serial number, which was a bit of a hassle.?
?
I wish the new owner success with the jeep and hope he has it ready for the Independence Day Parade here. I included a stripped R392/URR and the mating T-195 transmitter with jeep mounting platform. The T-195 was complete but I removed and destroyed the dynamotor. [like I need 1000V at 100mA] There's no way the T-195 would meet any modern transmitter specification and the high voltage could be lethal. It looks complete so the new owner is happy, although the R392/T-195 were really Korean conflict era comm gear. I tossed in some late WWII era "walkie talkies" and field phones. I pulled the crystal from the walkie talkie transmitter. No sense having someone come up around 50 MHz and get in trouble.
?
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Re: OFF-TOPIC: Jeeps, shifting, and snow (was: Batteries)
My truck is also non-synchronous, double clutching is absolutely required. It becomes second nature once you grab ahold of the floor shifter. Dan On Wednesday, March 5, 2025 at 12:20:53 PM EST, wn4isx via groups.io <wn4isx@...> wrote: On Tue, Mar 4, 2025 at 06:31 PM, Dan Kahn wrote: Do you still have the Jeep? I restored a 1939 Plymouth Pickup truck and would love to restore a Jeep.No, I traded it to a WWII reenactor. My father bought the jeep new surplus in 1949. The state decided the original bill of sale was OK for licensing. The jeep ran fine in 1975 when Dad realized he wasn't going to drive it again. It had just over 400 miles on it. I suspect all the rubber would need to be changed. It was stored inside so the paint was like new.? Fortunately there is a fairly large group of WWII jeep enthusiasts so parts won't be hard to locate. ? I 'learned' to drive in that jeep. Across cornfields that had been harvested. I'd just turned 9 and could barely reach the pedals and hang on to the steering wheel. ? And forget synchromesh transmissions, double clutching was an experience.? Fortunately they were made for rough service.?? ? One thing about WWII jeeps is they have a high center of gravity and you can roll them in a heartbeat. I nearly managed it at 20MPH in fairly soft dirt when I turned too sharply. ? ? |
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OFF-TOPIC: Jeeps, shifting, and snow (was: Batteries)
wn4isx
On Tue, Mar 4, 2025 at 06:31 PM, Dan Kahn wrote:
Do you still have the Jeep? I restored a 1939 Plymouth Pickup truck and would love to restore a Jeep.No, I traded it to a WWII reenactor. My father bought the jeep new surplus in 1949. The state decided the original bill of sale was OK for licensing. The jeep ran fine in 1975 when Dad realized he wasn't going to drive it again. It had just over 400 miles on it. I suspect all the rubber would need to be changed. It was stored inside so the paint was like new.? Fortunately there is a fairly large group of WWII jeep enthusiasts so parts won't be hard to locate.
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I 'learned' to drive in that jeep. Across cornfields that had been harvested. I'd just turned 9 and could barely reach the pedals and hang on to the steering wheel.
?
And forget synchromesh transmissions, double clutching was an experience.?
Fortunately they were made for rough service.??
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One thing about WWII jeeps is they have a high center of gravity and you can roll them in a heartbeat.
I nearly managed it at 20MPH in fairly soft dirt when I turned too sharply.
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Re: Slew rate and BW logic when designing differentietor of a pulse
john23,
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I uploaded this file:
which is in this group's Temp directory in Files.
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Run it, then click in the plot window, and press the Spacebar to re-load the plot settings.? It compares the circuit's actual response with the ideal derivative of the input voltage.
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You can see that the circuit fails to approximate the derivative.? The ideal output at V(out) should be the negative of the derivative of V(in), but it does not look like that at all.? So when you wrote that the circuit is "working", all I can say is that it is working extremely poorly.? It lacks the bandwidth needed to approximate the actual derivative of the input pulse.? For the 1 ns rise time, the extreme leading edge of V(out) somewhat follows the derivative of V(in), but it is in the wrong direction!? Then several nanoseconds later it swings down, and then rings.? So it is completely wrong, lacking bandwidth.
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I thought the response might have been coupling via another mechanism, but it is not that.? It is doing the best that it can, with too little bandwidth.? That's all.? Its output voltage wiggles, but wrongly.
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Andy
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File /Temp/AD8034_differentiator.zip uploaded
#file-notice
Group Notification
The following items have been added to the Files area of the [email protected] group. By: Andy <ai.egrps@...> Description: |
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Re: Batteries
开云体育I know what you mean and agree it would be better if a non-standard size. On a practical basis, if someone is paying $20-30 for a battery, it is not left on the kitchen table. These batteries typically are strictly inventoried by the companies that buy them.? Military, space, and other critical applications. Bertho ? From: [email protected] <[email protected]> On Behalf Of Andy via groups.io
Sent: 4 March, 2025 20:44 To: [email protected] Subject: Re: [electronics101] Batteries ? On Tue, Mar 4, 2025 at 11:24 AM, Bertho wrote:
I get that. ? But the problem is they are selling them in the AA, C, and D form-factors, where the expected voltage is 1.5 V, not 3.6 V.? That is a catastrophe waiting to happen. ? Andy ? |
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Batteries
On Tue, Mar 4, 2025 at 11:24 AM, Bertho wrote:
I get that. ?
But the problem is they are selling them in the AA, C, and D form-factors, where the expected voltage is 1.5 V, not 3.6 V.? That is a catastrophe waiting to happen.
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Andy
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Re: Slew rate and BW logic when designing differentietor of a pulse
john23,
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Every time you delete and re-send a message, that is one more message we receive from you.
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So far I have received 6 messages that you've sent in this topic, but only 2 remain.? You can't delete the ones in our email.? I know it can be difficult, but try to get the messages right before sending, so that you don't need to delete and re-send over and over.
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Andy
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Re: Slew rate and BW logic when designing differentietor of a pulse
On Tue, Mar 4, 2025 at 03:39 PM, john23 wrote:
From the datasheet and a few calculations.
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Your simulation uses +/- 7.5 V power.? Let's assume the output can approach (not reach) the rails.? The output pin sees R2 = 200 ohms to a virtual ground.? 7.5 / 200 = 37.5 mA.? The datasheet shows output short-circuit current = 40 mA typical with +/- 5 V supplies.? ?That is not guaranteed.? Figure 37 shows the output saturation voltage, where the output can't source or sink any more current.? It starts limiting around 25 mA, which is less than 37.5 mA, and again that is typical.? Let's say the minimum at clipping is 20 mA, which limits your outputs to only half the supply voltages (clips at +/- 4 V because of the 200 ohm load).
With the circuit wired as it was simulated, see at what point the output voltage clips.? Again, keep in mind it is typical only; worst-case will be worse than what is measured.
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Andy
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Re: Wireless Camera repair
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Re: OFF-TOPIC: Jeeps, shifting, and snow (was: Batteries)
Do you still have the Jeep? I restored a 1939 Plymouth Pickup truck and would love to restore a Jeep. Dan Kahn Newfoundland PA On Tuesday, March 4, 2025 at 03:39:56 PM EST, wn4isx via groups.io <wn4isx@...> wrote: On Tue, Mar 4, 2025 at 08:45 AM, Donald H Locker wrote: until I clear out "all that stuff you've got here!In our case it was me who decided "Dear God I've got to downsize!" I had about 30X30X20 in the corner of a warehouse filled with 'stuff.' I even had a WWII era jeep. That was a nightmare to license and transfer. I'm down to a few photocopy boxes of stuff I have to do some serious thinking. It might be worth the effort to sell on Ebay.? I found stuff I had no idea I had or where it came from. ? The university used to have surplus property auctions the 3rd Thursday of most months and I'd visit afte the big boys took what they wanted and pick out some "gold". a brand new Bird termaline watt meter, a perfect Bird throughline VSWR meter, audio oscillators, radiation detectors out the ying yang. All sorts of goodies that I'll never use. ? There is a certain feeling of freedom getting rid of stuff you'll never use. ? ? ? ? |
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Re: Slew rate and BW logic when designing differentietor of a pulse
Hello Andy , regarding the 200Ohm load,How did you? see that I am over loading the opamp?
Could you say what measurement needs to be done and where in the datasheet I need to look for this issue to see that I am not ruining the OPAMP?
Thanks.
https://www.analog.com/media/en/technical-documentation/data-sheets/ad8033_8034.pdf |
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OFF-TOPIC: Jeeps, shifting, and snow (was: Batteries)
wn4isx
On Tue, Mar 4, 2025 at 08:45 AM, Donald H Locker wrote:
until I clear out "all that stuff you've got here!In our case it was me who decided "Dear God I've got to downsize!" I had about 30X30X20 in the corner of a warehouse filled with 'stuff.'
I even had a WWII era jeep. That was a nightmare to license and transfer.
I'm down to a few photocopy boxes of stuff I have to do some serious thinking.
It might be worth the effort to sell on Ebay.?
I found stuff I had no idea I had or where it came from.
?
The university used to have surplus property auctions the 3rd Thursday of most months and I'd visit afte the big boys took what they wanted and pick out some "gold". a brand new Bird termaline watt meter, a perfect Bird throughline VSWR meter, audio oscillators, radiation detectors out the ying yang. All sorts of goodies that I'll never use.
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There is a certain feeling of freedom getting rid of stuff you'll never use.
?
?
?
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Re: Batteries
On Tuesday 04 March 2025 09:08:34 am Bertho wrote:
For the ultimate lithium battery (cell) see:That's one heck of a temperature range, there... And a 40 year lifespan? Wow. -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin |
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Re: Batteries
开云体育Andy, When that type of performance is needed, it is a custom design project and not for the general public. I do not expect the batteries will be replaced in my lifetime. When the equipment is mounted at a top of a pole and a bucket truck is required for service, and the road lane needs to be closed, the mechanical size/cost is not an significant issue. Regular rechargeable lithiums are also around 3.6V so no surprise. Amazing batteries! Bertho ? From: [email protected] <[email protected]> On Behalf Of Andy via groups.io
Sent: 4 March, 2025 10:27 To: [email protected] Subject: Re: [electronics101] Batteries ? On Tue, Mar 4, 2025 at 09:23 AM, Bertho wrote:
Darn!? All these alternate technologies!? With built-in ways to mess us up. ? Those Tadiran cells come in standard AA, C, and D form factors, but do NOT have the standard voltage.? Their nominal voltage in those form factors is 3.6V.? Now that's a million catastrophies just waiting to happen. ? THIS is the kind of thing that should never have happened.? Shame on them. ? Hopefully their very high cost will deter most people from using them in equipment designed to accept AA, C, or D dry cells. ? I also wonder why anyone would design equipment to accept 3.6V cells with AA, C, or D form factors.? Do traffic control equipment designers really do such a thing?? Or do they take the smart route and only use the alternate form factors? ? Andy ? |
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Re: IR digital cameras (was: Batteries)
wn4isx
Some Panasonic digital cameras are fairly easy to modify.
You remove the IR blocking filter from the CCD camera.
With this mod you'll get a mix of visible light and IR, I still had the IR passive lens from my childhood, I hang on to almost everything, spent the last 6 months getting rid of stuff.
Anyway there are two different IR passive filters, one is very deep red, the other appears black.
To use the "black" one requires the camera to be locked down on a tripod, you focus with the deep red, then change to the "black" filter and take your photo. Back then we used 100W incandescent bulbs on each side at roughly 45 degree angles.
Today you can see what the camera is seeing on the LCD screen, a heck of a lot easier.
I built an LED IR illuminator and I can mount the array using the quarter inch tripod mount.
I've built a 'gun' frame the camera is mounted on and the LED array is above the camera.
Looks like something from a cheap SF movie but it works pretty well.
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The built in xenon strobe produces very little IR. It's no big deal because I simply turn the flash off.
I have an IR blocking filter so I can mount it on the camera and use it for visible light but my wife has a ice Kodak digital camera we use for visible light and the camera on my cell phone is surprisingly good. It is 12 megapixals.
The big weakness with cell phone cameras isn't the CCD camera but the lens. Real cameras have sophisticated lens, multiple lens, each with a special diachromatic coating to reduce lens flare etc.
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My cell phone has a higher bit count then the Sony broadcast cameras we used at my last job.
Of course the lens for those cameras cost about 100k each.?
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I have the image intensifier lens from a 3nd generation night vision scope. it's an odd shape and I probably need to learn to print a plastic case. I'd love to interface a TV or still camera to the intensifier but optics gets complicated and really tricky.
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I have the output lens from a WWII sniper scope that used a "car" headlight with a gel IR filter to illuminate the scene. I had the entire sniper scope but the image converter tube went gassy after a decade or so.
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I need to come up with a lens to feed the image to the intensifier tube. This is probably a "I'd really like to make this work but I don't know enough." project. The tube is a reject because it has one more pixel defect then the specs allow.
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Given US regulations on such "high tech" stuff I can't go into any real details. Which is silly because a friend has a late model Russian night scope so clearly the secret is out there.
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""On the same note, it is a violation of ITAR to allow any non-U.S. citizen to look through U.S. Gen3 night vision equipment (even on US Soil). They are also not allowed to have access to any operator’s manuals or documentation, whatsoever, pertaining to US Gen 3 Night Vision Devices. This is a little-known fact about ITAR and Night Vision Devices, but it is true. We have confirmed this with the US State Department and major Night Vision Manufacturers. At TNVC, we take great care to ensure our clients are properly informed on laws and regulations pertaining to night vision. ""
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Re: Slew rate and BW logic when designing differentietor of a pulse
On Tue, Mar 4, 2025 at 06:50 AM, Michael Dunn wrote:
Agreed. ?
Be aware that you are also over-stressing the op-amp with the 200 ohm load.? That's 37.5 mA peak output, which it might not provide.? But I think that is unrelated to the question.
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Andy
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IR digital cameras (was: Batteries)
On Tue, Mar 4, 2025 at 08:37 AM, wn4isx wrote:
I wonder if that's true of all of them.? It probably is.? Photons are photons.? I know my first digital almost-SLR from 20+ years ago could, and I considered having the modification done to it.? I love IR photography, but never experimented with it.? I'm afraid it might become a "fad" that loses its appeal after a few hundred IR photos. Can't you just use the built-in flash? ?
Or did the camera's modification add an IR-only filter to the lens, making it insensitive to visible light?
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Andy
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Bertho
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