Search found 1590 matches

by dyarker
Mon Sep 07, 2020 3:13 pm
Forum: General Discussion
Topic: ADR421 Vref IC Low Short-Circuit Current!
Replies: 10
Views: 1578

Re: ADR421 Vref IC Low Short-Circuit Current!

The spec sheet title is ADR421. The "BRZ" on your parts might mean low power. A 1k load is a ridiculously heavy load for a precision reference. It is not a power supply regulator. -------------------------------------------------------- Yes, probably not oscillating. Did you place 2 small capacitors...
by dyarker
Mon Sep 07, 2020 2:31 am
Forum: General Discussion
Topic: ADR421 Vref IC Low Short-Circuit Current!
Replies: 10
Views: 1578

Re: ADR421 Vref IC Low Short-Circuit Current!

The spec sheet I'm looking at https://www.analog.com/media/en/technical-documentation/data-sheets/ADR420_421_423_425.pdf says 27mA is typical, not minimum. There is no minimum. So, the IC you got limits to a lower current to protect itself when a short is detected. A short is an error condition. Why...
by dyarker
Tue Jul 28, 2020 7:33 pm
Forum: General Discussion
Topic: Paralleling circuit breakers
Replies: 13
Views: 2378

Re: Paralleling circuit breakers

Nonsense, he said non equal current rated breakers.

And even if they were equal breakers, and the wires were just large enough not to overheat, they are not a load balance resistor.
by dyarker
Fri Jul 24, 2020 1:17 pm
Forum: General Discussion
Topic: Paralleling circuit breakers
Replies: 13
Views: 2378

Re: Paralleling circuit breakers

The resistances of the breakers is not directly related to current ratings. So, for example, with a 60A load the 15A breaker may pass 20A. The 15A breaker will trip. That leaves the 50A breaker with the whole 60A, it will trip too. Equal rating, same part number breakers will share the load more eve...
by dyarker
Thu Jun 18, 2020 10:16 pm
Forum: General Discussion
Topic: 4G LTE Interference on OTA Antenna TV
Replies: 16
Views: 2756

Re: 4G LTE Interference on OTA Antenna TV

Please read the posts before answering! This discussion was about towers on insulators. Which means RF hot tower. A hot tower needs a spark gap for lightning protection without shorting the signal. My mention of spark gap a couple posts back was for hot tower, obviously a non-hot antenna support tow...
by dyarker
Thu Jun 18, 2020 11:24 am
Forum: General Discussion
Topic: 4G LTE Interference on OTA Antenna TV
Replies: 16
Views: 2756

Re: 4G LTE Interference on OTA Antenna TV

The tower you say is 600ft not 2000ft. It supports other antennas so is unlikely insulated at the base. The mountain it is on is not relevant.

The big tube likely is waveguide, or coax.
by dyarker
Thu Jun 18, 2020 10:23 am
Forum: General Discussion
Topic: 4G LTE Interference on OTA Antenna TV
Replies: 16
Views: 2756

Re: 4G LTE Interference on OTA Antenna TV

A 1/2 wave antenna for an AM broadcast station could more than 400 ft.

(is 2000ft an over estimate?)
by dyarker
Thu Jun 18, 2020 10:06 am
Forum: General Discussion
Topic: Voltage and Current
Replies: 5
Views: 1418

Re: Voltage and Current

Electron flow, outside the source - electrons flow from the negative terminal through the external circuit to the positive terminal of the source. Inside the source the electrons are forced toward the negative terminal. The extra electrons at the negative terminal is what made it negative in the fir...
by dyarker
Wed Jun 17, 2020 5:11 am
Forum: General Discussion
Topic: Multisim simulation error in High-pass Filter Circuit Design
Replies: 2
Views: 851

Re: Multisim simulation error in High-pass Filter Circuit Design

Active filter? If yes, what cutoff/rolloff of the amplifier?

(images didn't work - had to ask)
by dyarker
Sat Jun 13, 2020 6:33 pm
Forum: General Discussion
Topic: 4G LTE Interference on OTA Antenna TV
Replies: 16
Views: 2756

Re: 4G LTE Interference on OTA Antenna TV

But the tower i mentioned...the insulator was at the base of the tower, not the base of the antenna..
Yes, I got that the insulator was at the base of the tower.

That means the whole tower is the antenna. I thought bolding the word "is" in my previous would have been clear enough.
by dyarker
Fri Jun 12, 2020 10:46 pm
Forum: General Discussion
Topic: 4G LTE Interference on OTA Antenna TV
Replies: 16
Views: 2756

Re: 4G LTE Interference on OTA Antenna TV

A tower on insulators is the antenna. There will be a spark gap at the base. Guy cables will have in-line insulators so that cable section lengths won't resonate at operating frequency.
by dyarker
Fri May 15, 2020 7:39 am
Forum: General Discussion
Topic: Superduper capacitor substitute for battery
Replies: 12
Views: 2018

Re: Superduper capacitor substitute for battery

Super caps have a higher internal resistance than filter caps. That is lucky because you don't mention current limiting, and you didn't "blow" the LED. LEDs are not incandescent bulbs. With bulbs an increase in voltage increases current, bulb gets hotter which increases resistance which regulates th...
by dyarker
Mon May 11, 2020 8:23 pm
Forum: General Discussion
Topic: Superduper capacitor substitute for battery
Replies: 12
Views: 2018

Re: Superduper capacitor substitute for battery

Thank you! (Wonder what I pushed on the calculator???)
by dyarker
Sun May 10, 2020 9:05 pm
Forum: General Discussion
Topic: Superduper capacitor substitute for battery
Replies: 12
Views: 2018

Re: Superduper capacitor substitute for battery

It was indirect. He said he expected AAs to last 30 minutes. If it is rated 1300mAHr, that is 1.3A for 1 hour. So 2.6A for half an hour. (Though at high current loads you don't get the rated time.) A lot of LEDs, a LED headlight, or an incandescent does not matter for the question; "How much capacit...
by dyarker
Sat May 09, 2020 12:34 pm
Forum: General Discussion
Topic: Superduper capacitor substitute for battery
Replies: 12
Views: 2018

Re: Superduper capacitor substitute for battery

Just spotted a 3500F super-super-cap.

One or two of those should do too.

(a question - is this an incandescent light? because the white LEDs I've seen need 3.8V)