True RMS vs averaging DMM
- Thread starter Tubetec
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scott2000
Well-known member
You first...lol
user 37518
Well-known member
The Agilent U1253A battery lasts around 4-10 hours! this is due to the fact that it uses an OLED screen, it looks beautiful though, the designers decided to use a 9V rechargable battery, not a good choice. I haven't seen any meter with less battery time than this, ever.... Plus, the screen has a limited life time, over time (whether you use it or not) it becomes dark up to the point that it just fails, Agilent/Keysight wont replace it nor will they offer the spare parts, the only available option is a guy from China who sells them at TaoBao, I had to replace mine.
Really bad design because the meter is down when recharging. I gave up on that fast and use a regular toxic landfill type.
user 37518
Well-known member
How much do they last? I was planning on doing it but seems like I would need an endless amount of batteries....
scott2000
Well-known member
Those Energizer Industrial ones are pretty impressive. My brother in law loaned me an automobile scanner from his work , which hadn't been used in forever, the terminals inside the scanner actually rusted apart, and the batteries were still like new and tested as . Not sure how long they can supply the juice though....
That’s why it became the country cabin meter…
They should have sent it with two rechargeable batteries and a wall charger. Having it charge the battery through the probe ports is idiotic.
If I ever have a dacha, absolutely no voltages allowed.
Mike
It’s two garden sheds. I charge batteries so there is light for 5 days. The propane lights in the other cabin are a PITA. After 5 years of lugging batteries I’m getting real electricity. I’m waiting for Nat Grid to install a pole. Then it’s a 450 foot run in a trench to the cabins.
Have you ever considered solar ?
It’s heavily forested and in the winter there is very little sun. If it is supposed to supply heat in the winter I’d have to clear a lot of land and it would be hugely expensive. Even in the summer there can be little sun. It’s almost a rain forest.
I didn't suggest that. Just lighting. I have solar lamps lighting the driveway and the garage entrances.
I tried. In the winter I got less than 5W from two 400W panels. For less than six hours a day.
Damn!
I got a small solar panel years ago (12 watt) , in winter I use it to keep my mower battery in good condition ,connects directly across the battery and pulses quicker or slower depending on the intensity of the light .
Its useful for car batteries too , you place the panel on the back window and plug the unit into the lighter socket .
The small panel cost around 10 euros and in the end I got more than 10 years useage from that battery .
I bought a UNi-T 171b before I got the Fluke , I though initially the rechargable battery was a good plan .
Like the Keysight it charges through the probe ports with the switch in the off position , its not a regular 9v cell but a specific two cell lipo with a jst connector , I much prefer the Fluke with standard AA(187) or 9v cells (77IV), if you want rechargeable you do the charge externally from the meter .
Maybe you could have installed a solar panel up in the canopy to gather more light Paul , never the less clearing an area in the vicinity of your cabin might be a good plan to prevent the chances of fire during the hotter summer months .
Ive recently got myself an army style 'basha' shelter for getting out of the rat race every once in a while , Ive used a pair of telescopic hiking poles (with a removable spike installed at the handle end) , bungee cords and a small pulley in each corner , its set up and water proof in only minutes . I was also able to get several other nice accessories for it from my local army surplus , artic grade sleeping bag with washable liner , insect net and bivi bag and I even picked up a really nice 55L rucksack for 5 euros from a thrift store . Its way more versatile than a tent and can be set up in many different configurations depending on usage and territory . Another plus point is the basha sheet itself is modular ,enabling two or more sheets to be clipped together to make a larger shelter .
I got a led light with motion detection sensor and seperate solar panel , that is easily mounted either inside or outside the tent depending on what you need . I'm still testing in the back garden for now ,gradually adding the various pieces of kit I need . I did find some usefull remote controlled battery powered led lamps, they have RGB so you can mix the colours and they even come with a small keyfob remote , very handy for locating your hide in dense undergrowth , especially if you have a few beers down the hatch returning from the pub late at night .
Im really having a lot of fun with this , I cant wait to try it out .
Its useful for car batteries too , you place the panel on the back window and plug the unit into the lighter socket .
The small panel cost around 10 euros and in the end I got more than 10 years useage from that battery .
I bought a UNi-T 171b before I got the Fluke , I though initially the rechargable battery was a good plan .
Like the Keysight it charges through the probe ports with the switch in the off position , its not a regular 9v cell but a specific two cell lipo with a jst connector , I much prefer the Fluke with standard AA(187) or 9v cells (77IV), if you want rechargeable you do the charge externally from the meter .
Maybe you could have installed a solar panel up in the canopy to gather more light Paul , never the less clearing an area in the vicinity of your cabin might be a good plan to prevent the chances of fire during the hotter summer months .
Ive recently got myself an army style 'basha' shelter for getting out of the rat race every once in a while , Ive used a pair of telescopic hiking poles (with a removable spike installed at the handle end) , bungee cords and a small pulley in each corner , its set up and water proof in only minutes . I was also able to get several other nice accessories for it from my local army surplus , artic grade sleeping bag with washable liner , insect net and bivi bag and I even picked up a really nice 55L rucksack for 5 euros from a thrift store . Its way more versatile than a tent and can be set up in many different configurations depending on usage and territory . Another plus point is the basha sheet itself is modular ,enabling two or more sheets to be clipped together to make a larger shelter .
I got a led light with motion detection sensor and seperate solar panel , that is easily mounted either inside or outside the tent depending on what you need . I'm still testing in the back garden for now ,gradually adding the various pieces of kit I need . I did find some usefull remote controlled battery powered led lamps, they have RGB so you can mix the colours and they even come with a small keyfob remote , very handy for locating your hide in dense undergrowth , especially if you have a few beers down the hatch returning from the pub late at night .
Im really having a lot of fun with this , I cant wait to try it out .
Last edited:
- Joined
- Jul 8, 2010
- Messages
- 472
with 19 kHz and 20 kHz which one is the carrier?
[edit- back in the 70s when I converted my heathkit SMPTE IMD to work with 19/20kHz I used the simple average meter in the Heathkit. I guess this makes all my benchwork back then suspect?[/edit]
JR
The carrier is the sum of the two.
If 19/20 kHz are at 1:1 ratios the power sum is +3 dB.
I measured the average level, on multiple average-responding meters, to be about 1.4 dB lower when compared to the RMS-responding Fluke and RMS-responding FFT measurements which correctly show a +3 dB sum.
I don't think the 1.4 dB difference makes your bench work suspect.
I like Fluke the 8050A and also own an 8060 I used for field service.
The pic is from when I had four, I now have five 8050As in my measurement stack.
One interesting trick I learned is that it can do dB measurements in the DC measurement mode.
For really accurate attenuator measurement I use DC as the stimulus.
The DC dB measurements come in handy.
The 8060s LCD display can often be repaired by cleaning the electro-tin-plated PC board contact to Zebra strip elastomeric connector "interface."
I use a dry Q-tip to burnish the PC board fingers.
When those are cleaned missing segments on the display will often come back to life.
I bought a replacement LCD years ago and never used it because I was able to refurbish the old one.
The 8050As are inexpensive on eBay and usually have two problems: Bad LCDs or NiCd batteries.
The batteries are easily-replaced and the unit won't run without them.
- Joined
- Jul 8, 2010
- Messages
- 472
OT but I hope they have a transformer in stock to install.
I have a friend in rural OK who has been waiting months for his utility to get delivery of a pole pig.
The back-order times are crazy long.
They said 4-8 weeks. I sent the final paperwork in yesterday.
Newmarket
Well-known member
"Maximum Voltage" ?
Do you mean "Minimum Voltage" there ?
The maximum would be whatever circuit can withstand without something overheating and being damaged or wrt the 7812 cutting out.
moamps
Well-known member
Ha, I was already thinking of deleting that post
. It is a question of measuring the maximum permissible AC voltage (ripple) modulated to DC.
