## Search found 6217 matches

Thu Mar 26, 2020 10:17 am
Forum: General discussion
Topic: what happened to the raspberry pi 4 1GB?
Replies: 23
Views: 778

### Re: what happened to the raspberry pi 4 1GB?

If new cars are better than old ones, does the same apply to buildings?

And, if so, should we knock down Stone Henge and replace it with an apartment block?
Thu Mar 26, 2020 9:48 am
Forum: Troubleshooting
Topic: Simple switch with extended cable
Replies: 4
Views: 127

### Re: Simple switch with extended cable

0μ1F = 0,1μF = 0.1μF = 0u1F Half the world uses a fullstop as a decimal separator, while the other half uses a comma. The rest of the world can't find either of those on their keyboard, so they put the multiplier (p, n, μ, m, k, M, G, T, ...) in its place. And many of us can't find the μ so we use u...
Thu Mar 26, 2020 9:33 am
Forum: Beginners
Topic: Controlling 24V AC Solenoid Valve by solid state relay
Replies: 3
Views: 104

### Re: Controlling 24V AC Solenoid Valve by solid state relay

gannonziviello wrote:
Tue Mar 24, 2020 9:24 pm
... The power supply is a standard American wall outlet.
Should we interpret that as a "wall-wart", plugged into a socket and producing 24V AC on the end of a pair of wires?
If so, as long as it can supply enough current for the two valves, safety should already have been taken care of.
Thu Mar 19, 2020 10:08 am
Forum: General discussion
Topic: Problem with GPIO and relay
Replies: 11
Views: 357

### Re: Problem with GPIO and relay

http://www.farnell.com/datasheets/2626620.pdf?_ga=2.180659879.1406569187.1584567076-883246931.1584567076 On page 5, the table gives 40mA for the 5v version. That's far too much for a GPIO to supply - 16mA is the most you should take from a GPIO. As pcmanbob says, you need a driver circuit between th...
Tue Mar 17, 2020 10:06 am
Forum: Wanted
Topic: Control/interface board for 7" display
Replies: 6
Views: 586

### Re: Control/interface board for 7" display

A piece of cardboard could be used to jam the ribbon in place - not too thick, but thick enough, you'll have to experiment.
Sat Mar 14, 2020 6:42 pm
Forum: General discussion
Topic: So, what's the big new thing for this year's Pi Day (8th anniversary) ?
Replies: 129
Views: 6657

### Re: So, what's the big new thing for this year's Pi Day (8th anniversary) ?

MRV wrote:
Sat Mar 14, 2020 8:56 am
3.14 - 9:53 am - Italy
Woke up.
Went to the kitchen.
No new pies.
Back to sleep.
The devil's in the detail.
Eighth Birthday means you should have gone to bed with eight lit candles, four on each side, ready for blowing out in the morning.
Not sure whether they're with or without the forks
Fri Mar 13, 2020 11:41 am
Forum: Troubleshooting
Topic: Mfg part number for inductor L1 rpi 4B
Replies: 1
Views: 92

### Re: Mfg part number for inductor L1 rpi 4B

Yes, I believe it's L1, but unless one of the RP engineers says different, all we know is what's on the diagram.

Though I would be surprised if the only damage is the broken L. Most likely, you've also broken the chip aswell
Tue Mar 10, 2020 6:54 pm
Forum: Troubleshooting
Topic: Offical Rasberry Pi 7in'' Touchscreen Flickering with relays
Replies: 31
Views: 796

### Re: Offical Rasberry Pi 7in'' Touchscreen Flickering with relays

The Relay has to get power from the pi to be controlled by the Pi I've tried powering it separate as well. It is connected via GPIO pins and the 5v pin ( it does not work with the 3v3) it is also grounded on one of the pi's ground pins. The Amazon 4-relay board has a "JD-VCC - VCC" link. If you rem...
Tue Mar 10, 2020 12:04 pm
Forum: Other projects
Topic: RP as Atomic Clock broadcast
Replies: 5
Views: 353

### Re: RP as Atomic Clock broadcast

One problem you might not have thought about: So you successfully create a 60kHz signal for your own clocks, and they're locking to it correctly. But just down the road, someone else's clocks now have two signals to lock to, and they can't know which is correct. If all else fails, that someone also ...
Mon Mar 09, 2020 10:46 am
Forum: General discussion
Topic: Power 3x RPi Zero W from mains 230VAC
Replies: 10
Views: 483

### Re: Power 3x RPi Zero W from mains 230VAC

I believe the "illegal" claim was in reference to installing a hidden camera inside a fake light, which is indeed illegal, but only if you do not inform people the area is being surveiled. Although that kind of defeats the purpose of it being hidden, doesn't it. Do I have to inform potential burgla...
Sat Mar 07, 2020 6:50 pm
Forum: Troubleshooting
Topic: Yellow bolt and undervoltage detection
Replies: 22
Views: 805

### Re: Yellow bolt and undervoltage detection

the batteries are two pieces of 4200mah so it should be 8400mah total but i don't know why the Raspberry and the monitor stay on just for 1 hour. It seems this device support max 8A and i think that change the batteries with others with higher amperage will not help. How could it be that 8400mah la...
Thu Mar 05, 2020 11:08 am
Forum: Beginners
Topic: Safe 4 push button layout?
Replies: 3
Views: 157

### Re: Safe 4 push button layout?

I want to have 4 push buttons attach to the raspberry pi. Is the layout below safe to use (current draw, shorts, etc)? I'm using pull down for all of them. Thank you! https://imgur.com/a/RB1mUTF The image doesn't appear to be liked by the forum software, so here it is again: M9UynJr.png Yes, it sho...
Wed Mar 04, 2020 6:57 pm
Forum: Beginners
Topic: Why is NOOBs suggested to be used by Raspberry beginners?
Replies: 51
Views: 2301

### Re: Why is NOOBs suggested to be used by Raspberry beginners?

RPF recommend NOOBs; lots of first-time posters come here with problems caused by NOOBs; "ditch it", they're told, and they go away happy. Or do they? Do they, perhaps go away frustrated? And the other statistic we don't know is how many people don't post here because they don't have problems with N...
Tue Mar 03, 2020 6:53 pm
Forum: Beginners
Topic: Wiring Harness
Replies: 4
Views: 253

### Re: Wiring Harness

The Google you're looking for is "40-way ribbon cable"
Tue Mar 03, 2020 11:08 am
Forum: Troubleshooting
Topic: raspberry pi will not start up after i reset its card
Replies: 2
Views: 124

### Re: raspberry pi will not start up after i reset its card

The "No Signal" sign is created by your monitor, not the Pi.

Unplugging and waiting is to allow the Pi's resettable fuse time to reset itself. It may help, until the next time the fuse pops ...

Have you tried Etching a fresh copy of Buster onto your SD card?
Tue Mar 03, 2020 11:01 am
Forum: Graphics, sound and multimedia
Topic: HDMI input for pi 4
Replies: 5
Views: 364

### Re: HDMI input for pi 4

nathanlitjens wrote:
Tue Mar 03, 2020 2:30 am
... images from a hdmi connected, sensor triggered dslr ...
The Pi has no hdmi input, so you cannot grab images from the dslr that way.

The second hdmi socket is a second hdmi screen output
Tue Mar 03, 2020 10:58 am
Forum: Beginners
Topic: Raspberry Pi Zero power supply
Replies: 3
Views: 185

### Re: Raspberry Pi Zero power supply

Although only one USB port has the data lines connected, so only that one can be used for interfacing with the Pi, both have power and ground connected directly to the Pi's power rails, so either can be used to provide power. In fact, if you plug your Zero into your laptop as a gadget, that's how it...
Tue Mar 03, 2020 10:50 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: How to wire a Raspberry Pi to a Sainsmart 5v Relay Board
Replies: 88
Views: 241744

### Re: How to wire a Raspberry Pi to a Sainsmart 5v Relay Board

bwertman wrote:
Mon Mar 02, 2020 8:49 pm
... The other outlet would consistently read 120v with my dvom but when I plugged the same device into it, it would not power it.
That suggests your 120v wiring is seriously awry. Have that checked by Someone Who Knows before you hurt someone.
Mon Mar 02, 2020 6:35 pm
Forum: Troubleshooting
Topic: Being told USB wasn't ejected after ejecting and taking USB out
Replies: 3
Views: 147

### Re: Being told USB wasn't ejected after ejecting and taking USB out

When you tell the Pi (or any other computer) to "eject" a device, it tells the device to clean itself up, stop its housekeeping, and get ready for power-down.
Some of these things can take ages to sort themselves out - like a child getting ready for bed.
Sat Feb 29, 2020 12:13 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Measuring small change in resistance with ADS1015
Replies: 21
Views: 997

### Re: Measuring small change in resistance with ADS1015

Perhaps you could show us a diagram of your proposed circuit, then we can make recommendations?
Sat Feb 29, 2020 12:08 pm
Forum: Beginners
Topic: Is it safe to build circuit after boot?
Replies: 16
Views: 812

### Re: Is it safe to build circuit after boot?

My take on this: powering down before changing things is a good habit to get into, like wearing a helmet when riding a bike. You may never be hit by a double-decker bus, but if it does happen, it'll happen when you forget your helmet. If you get into the habit of powering down, you'll still make mis...
Sat Feb 29, 2020 12:02 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: I2C and 5V - Definitive answer?
Replies: 28
Views: 7558

### Re: I2C and 5V - Definitive answer?

But making long story short - now I connected display using 3.3V line and it works (however I had to set contrast screw to maximum to see text). My question is: Is that safe? Can I use display connected like that? Or maybe I should order anyway the converter? Will that one be good?: https://www.ama...
Sat Feb 29, 2020 11:03 am
Forum: General discussion
Topic: Black and White display
Replies: 1
Views: 130

### Re: Black and White display

Assuming you're using the composite video on the trrs jack, have a look at https://www.raspberrypi.org/documentation/configuration/config-txt/video.md Setting sdtv_disable_colourburst to 1 disables colourburst on composite video output. The picture will be displayed in monochrome, but it may appear ...
Fri Feb 28, 2020 7:09 pm
Forum: Graphics, sound and multimedia
Topic: Question about Audio Jack spec from Raspberry Pi 3
Replies: 1
Views: 378

### Re: Question about Audio Jack spec from Raspberry Pi 3

Almost nothing there is official, and things have moved on in the intervening six years. However, if you look at the reduced schematic at https://www.raspberrypi.org/documentation/hardware/raspberrypi/schematics/rpi_SCH_3b_1p2_reduced.pdf you'll see that it's driven from an amplifier, powered from 3...
Fri Feb 28, 2020 10:58 am
Forum: Beginners
Topic: Can i use aux cable for audio output from Raspberry pi 3 or 4?
Replies: 2
Views: 367

### Re: Can i use aux cable for audio output from Raspberry pi 3 or 4?

hello. Can i use Aux cable for audio out put from raspberry pi 3 or 4 in its 4-pole stereo audio and composite video port ? I m afraid it might cause short circuit. Will it? Already asked: https://www.raspberrypi.org/forums/viewtopic.php?f=91&t=266460 Which is the chicken, which is the egg? https:/...