Go to advanced search

by davidcoton
Wed Sep 18, 2019 9:17 am
Forum: General discussion
Topic: Raspberry Pi and Fotek SSR-25
Replies: 4
Views: 100

Re: Raspberry Pi and Fotek SSR-25

If your part in genuine it should work, but the trigger current is a little high (7.5mA) if you are drawing current from other GPIOs at the same time. A transistor to switch 5V to the trigger should solve it. Specification Edit: the default GPIO drive strength only guarantees V IH > 1.6V at 8mA, whi...
by davidcoton
Wed Sep 18, 2019 12:18 am
Forum: Beginners
Topic: Leak sensor too sensitive
Replies: 2
Views: 43

Re: Leak sensor too sensitive

Small capacitor (try 0μ1) base to emitter?
by davidcoton
Tue Sep 17, 2019 1:54 pm
Forum: General discussion
Topic: Low voltage warning even though gpio being powered with 5.07V?
Replies: 10
Views: 371

Re: Low voltage warning even though gpio being powered with 5.07V?

Botspot wrote:
Tue Sep 17, 2019 1:43 pm
What wire thickness is necessary?
At least 24AWG. Preferably 18AWG.
by davidcoton
Tue Sep 17, 2019 9:21 am
Forum: General discussion
Topic: RP4 USB Battery Power - E Marked Issue
Replies: 9
Views: 356

Re: RP4 USB Battery Power - E Marked Issue

Why do you advise against the Power Delivery spec? It is, after all, specifically for use as a power supply, up to 100W@5v. That's literally what the spec is for. See this Wikipedia article. The power limit at 5V is 15W (3A -- yes even the official Pi PSU does that). Higher power requires higher vo...
by davidcoton
Mon Sep 16, 2019 8:41 am
Forum: General discussion
Topic: Laptop speakers with Raspberry PI
Replies: 25
Views: 551

Re: Laptop speakers with Raspberry PI

W. H. Heydt wrote:
Mon Sep 16, 2019 1:05 am
That is the sort of information that should have been provided at the beginning. How were we to know you had such severe space constraints?
OP's third post:
qaz wrote: The thing is that I need really thin speakers, so dunno. These are the things I thought of...
by davidcoton
Sun Sep 15, 2019 10:58 pm
Forum: Beginners
Topic: Pi 3 Model B GPIO Questions
Replies: 6
Views: 123

Re: Pi 3 Model B GPIO Questions

Careful. You are showing the first signs of PAD (Pi Addiction Disorder). It will take over your life completely if you let it.

With only one Pi, it's not an advanced case. Yet. :twisted:
by davidcoton
Sun Sep 15, 2019 10:55 pm
Forum: Beginners
Topic: Soldering
Replies: 22
Views: 462

Re: Soldering

AIUI that's how boards with a separate pad for each hole should be used -- either use the ends of the component/wire or a separate piece of hookup wire.
by davidcoton
Sun Sep 15, 2019 6:40 pm
Forum: Beginners
Topic: Pi 3 Model B GPIO Questions
Replies: 6
Views: 123

Re: Pi 3 Model B GPIO Questions

https://pinout.xyz/#
It's the same on all 40-pin Pis, and the first 26 are the same on later 26-pin models.
Only three pins are different (numbering only) on the earliest Pis.
by davidcoton
Sun Sep 15, 2019 6:30 pm
Forum: General discussion
Topic: Laptop speakers with Raspberry PI
Replies: 25
Views: 551

Re: Laptop speakers with Raspberry PI

qaz wrote:
Sun Sep 15, 2019 4:42 pm
But really, will it make a difference? Technically
The clue is in the name. Loudspeakers. More noise out, more power in required to drive them.
by davidcoton
Sun Sep 15, 2019 4:38 pm
Forum: General discussion
Topic: Laptop speakers with Raspberry PI
Replies: 25
Views: 551

Re: Laptop speakers with Raspberry PI

You don't want to walk around with a pair of speakers clipped over your ears.
by davidcoton
Sun Sep 15, 2019 4:30 pm
Forum: General discussion
Topic: Laptop speakers with Raspberry PI
Replies: 25
Views: 551

Re: Laptop speakers with Raspberry PI

Working backwards: That Amazon amp will only drive headphones, not speakers. HermannSW's suggestion will require more than £12 worth of time to assemble a working amp (and you will need to learn to solder, and to read Chinese :lol: ) The Pimoroni board should "just work"-- but you may still need to ...
by davidcoton
Sat Sep 14, 2019 2:27 pm
Forum: Troubleshooting
Topic: Buster updates started to fail at 22th August
Replies: 10
Views: 411

Re: Buster updates started to fail at 22th August

OK, so what happened to 'apt-get update'? Someone decided it wasn't broke, so... I would expect "update" to update any files/programs that have minor upgrades and changes I would expect "upgrade" to take me from stretch to buster - major upgrades and changes, new features For whatever reason, your ...
by davidcoton
Thu Sep 12, 2019 8:56 pm
Forum: Beginners
Topic: Relay - can it be used in reverse (signal microcontroller) ?
Replies: 14
Views: 549

Re: Relay - can it be used in reverse (signal microcontroller) ?

ejolson wrote:
Thu Sep 12, 2019 6:09 pm
Given the dangerous uses computers can be put to, perhaps someday coding will, in general, also require a government issued license.
No, the issue of licences will be privatised. That way more people can make more money out of the poor coding footsoldier.
by davidcoton
Thu Sep 12, 2019 8:52 pm
Forum: General discussion
Topic: RPI 4 USB-C supply
Replies: 37
Views: 1260

Re: RPI 4 USB-C supply

jamesh wrote:
Thu Sep 12, 2019 8:11 pm
Seems to are repeating ad nauseum the same old stuff. Lock the thread?
Yes please.
by davidcoton
Thu Sep 12, 2019 4:46 pm
Forum: General discussion
Topic: Make diy UPS for PI3
Replies: 19
Views: 21285

Re: Make diy UPS for PI3

dima91 wrote:
Thu Sep 12, 2019 4:17 pm
Did you find a solution DarkLegend?
DarkLegend has not logged in since Jan 2017.
by davidcoton
Thu Sep 12, 2019 12:58 pm
Forum: General discussion
Topic: RPI 4 USB-C supply
Replies: 37
Views: 1260

Re: RPI 4 USB-C supply

Does a standards compliant adaptor meet the Pi's requirements in all cases? Certainly USB 1.0 came out before such high current loads were envisioned. Not sure about USB 2.0 either. For USB 3.0 the requirement of +- 5% at the source's connector against the 5V nominal which puts a legal adaptor at 4...
by davidcoton
Thu Sep 12, 2019 12:26 pm
Forum: Beginners
Topic: Relay - can it be used in reverse (signal microcontroller) ?
Replies: 14
Views: 549

Re: Relay - can it be used in reverse (signal microcontroller) ?

I was hoping someone with common sense Would understand that an electrician would Be able to make safe connection to the existing Lighting circuit for him to fit the power adapter It then would be solid state no relays, In my time working as an electrician I have learnt that, unfortunately, common ...
by davidcoton
Thu Sep 12, 2019 12:00 am
Forum: Troubleshooting
Topic: Raspberry Pi 4 temperature
Replies: 529
Views: 132119

Re: Raspberry Pi 4 temperature

You cut and edited my response. The $100 would be viable for a pi 4B successor. Not an updated zero I clearly left your indicated price for an updated Zero. I did not misrepresent your message in my edit. A Zero at $25 is not viable. That's Pi3A territory now. And a price increase destroys the USP ...
by davidcoton
Wed Sep 11, 2019 10:19 pm
Forum: Troubleshooting
Topic: Raspberry Pi 4 temperature
Replies: 529
Views: 132119

Re: Raspberry Pi 4 temperature

The zero on the other hand, can improve by only a small performance boost, while having a potentially large cpu power consumption decrease. It won't need a lot more for a next model to be financially viable (at $25?). ... If they can be built Qualcomm quad/octa core chips on a 10-14nm node into $10...
by davidcoton
Wed Sep 11, 2019 6:23 pm
Forum: General discussion
Topic: 12v battery + 25 watt Solar = always powered 4B?
Replies: 17
Views: 519

Re: 12v battery + 25 watt Solar = always powered 4B?

There are several threads around here which discuss this. Basically a 25W panel will only produce 25W in good sunlight -- less than 12h a day even in the tropics. Allow for bad weather, conversion losses, winter, etc, etc, and you end up needing a much bigger panel and an enormous battery. The link ...
by davidcoton
Wed Sep 11, 2019 6:13 pm
Forum: Beginners
Topic: need help to prepare my sd card for using noobs installer
Replies: 4
Views: 141

Re: need help to prepare my sd card for using noobs installer

A far less complicated method is to download ETCHER (it's FREE). You can select ETCHER for Windows or Linux, 32 bit or 64 bit. Etcher will Format your SD Card properly, just follow the directions. I run ETCHER to format SD Cards on my Linux 19.2 system. No worries .... Good luck, you'll be fine. Et...
by davidcoton
Wed Sep 11, 2019 5:57 pm
Forum: General discussion
Topic: RPI 4 USB-C supply
Replies: 37
Views: 1260

Re: RPI 4 USB-C supply

Burngate wrote:
Wed Sep 11, 2019 5:00 pm
Jamesh... he's all-powerful
Is "all-powerful" more than 30W? :lol:
by davidcoton
Wed Sep 11, 2019 4:17 pm
Forum: Troubleshooting
Topic: RPi 4 2GB - Cant set gpu mem above 600 / black screen
Replies: 13
Views: 677

Re: RPi 4 2GB - Cant set gpu mem above 600 / black screen

navy1978 wrote:
Wed Sep 11, 2019 3:54 pm
I just received a new Raspberry 4 with 4GB and I have the same problem, any suggestion?
Leave gpu_mem at the default setting. This setting isn't used for display RAM on the Pi4B, instead memory is allocated directly in the main RAM area.
by davidcoton
Wed Sep 11, 2019 3:47 pm
Forum: General discussion
Topic: Raspberry pi 4 composite out don't working
Replies: 17
Views: 578

Re: Raspberry pi 4 composite out don't working

Thanks for the update. It hasn't affected me, but it's good to get a glimpse of your process and the changes an apparently small issue can provoke.

Keep up the bug squashing! Then on to something new? (Yes I know you probably can't/won't answer that :lol: )
by davidcoton
Wed Sep 11, 2019 10:46 am
Forum: Beginners
Topic: Getting start RPI.GPIO with raspberry pi 3 a+
Replies: 4
Views: 100

Re: Getting start RPI.GPIO with raspberry pi 3 a+

The blue line on the breadboard has a break, which probably corresponds to a break in the track. Link the two halves (also for the 3V3 track). Edit: photographic artifact? Try pcmanbob's suggestion below. Maybe also the switch orientation is wrong? BTW, help yourself (and everyone else) by using bl...

Go to advanced search