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USB 1500v Isolator Isolator ADUM4160 USB To USB ADUM4160/ADUM3160 Module New http://www.ebay.com/itm/-/172471559018
USB DC 5V to DC 9V/12V Step-up Module Converter 2.1x5.5mm Male Connector Plus http://www.ebay.com/itm/-/401215703430
USB 1500v Isolator Isolator ADUM4160 USB To USB ADUM4160/ADUM3160 Module New http://www.ebay.com/itm/-/172471559018
USB DC 5V to DC 9V/12V Step-up Module Converter 2.1x5.5mm Male Connector Plus http://www.ebay.com/itm/-/401215703430
I recently bought a usb keyboard vacuum which surged and stuffed my usb ports. I wish I had used an isolator.
Did you work out those resistors?
Showing my age now…
They were never accurate even new but a "ball park".
You could scrape the flat side, and slide the winding along to change the values and "tune them"
They used to have lacquer on them just to stop conduction,
They were made by Auther who would have his pipe and saw big long bars of the "material" with a old rule on a sloppy machine.
Made for a customer on bulk and generally untested, cut one, measure one and make adjustments and then cut 1000.
I'd assume them to be about 1940's.
Embarrassing, had the values worked out before you, body tip spot, showing my age, my father was a radio and TV repair man before me, and I think these are 1 and 2 watt resistors at quite high voltages, 500 &1000 volts.
If you were taking O'scope measurements on a device, which is connected to your PC for power, you don't want mains earth ground traveling from your PC through the USB connection to the device. You want the device as a floating reference. Otherwise should you connect probe ground to the wrong point you can blow up the device and an expensive scope probe also.
USB only guarantees 100mA of current delivery. With some negotiations, it can be raised to 500mA if device requests it and controller agrees. Yes, most devices do not negotiate and do assume 500mA is always available. But that is not the case. Also, this device only really supports USB 1.0. The assumption about 500mA available is only because of how battery chargers with USB output works. They are required to support at least 500mA, even without negotiation. But then if you plug a device designed to be charged by separate USB charger into your computer, and the device doesn't properly talk to controller, you can have a bad time. Fortunately most controllers do have active over-current protection or polyfuses to prevent this from happening. And most will be designed to support 500mA minimum anyway. But again that is not guaranteed. Especially dumb devices ignore all the negotiation protocols, like battery banks, most smartphones, and other "gadgets" powered by 5V USB stuff.
Any source cheap of High-Speed USB (aka USB 2.0, 480Mbps) isolators? Most of the one I can find are only Full Speed, 12Mbps, which is fine for connecting some instruments, multimeters, or serial stuff ~1Mbps to some mains powered stuff that might not be fully isolated (like power supply, inverter, DC-DC converter, etc), especially if some of various connected components do have separate grounds and potentials. But I would like to have High-Speed for some USB oscilloscopes for example.
Hi Julian, the old resistors are read by BED "body, end, dot" just as you sad, Clive on bigclive or was it Paul on mr carlsons lab (i cant quite remember) had a few and was explaining about them.
Love your channel, i watch it most the time.
I think Mr Carlson will be able to identify those resistors for you.
Watch out for the resistor asbestos.
So I bought a 12v plug to power my 12v 5m RGB 5050 led light strip and they cut out every few seconds. Is this because the lights draw too much current?
them isolators are good for usb headset that have an annying humming sound
Add a variable resistor to get adjustable voltage.😀
No more shopping while on the grogg.
I wonder what the power ratings are.