Search found 1471 matches

by ahull
Sat May 27, 2017 10:13 pm
Forum: Postbag
Topic: Andy's Postbag and random ebay links
Replies: 87
Views: 1694

Re: Andy's Postbag and random ebay links

I suspect you are correct about the mode of operation, however since it appears to rely on detecting a relative change in the oscillator, rather than an absolute frequency, then so long as the reflector is as effective at gathering the reflected signal as it is at boosting it in the wanted direction...
by ahull
Sat May 27, 2017 10:00 am
Forum: General discussion
Topic: Minimum ADC reference voltage?
Replies: 11
Views: 111

Re: Minimum ADC reference voltage?

@Roger Youtube user Julian Ilett does something similar here..



He describes the build of the "Arduino Ammeter" in a couple of earlier videos
by ahull
Sat May 27, 2017 1:18 am
Forum: General discussion
Topic: Minimum ADC reference voltage?
Replies: 11
Views: 111

Re: Minimum ADC reference voltage?

What sort of resolution do you require? If we assume that we can get 11bit resolution of a 3.3v signal, then each bit = 1/2048*3.3 or 0.001611328v, so your 0 to 0.1v signal would give you 62 steps of resolution without amplification, or around 7 bit accuracy.. for anything better, you would indeed n...
by ahull
Fri May 26, 2017 11:20 pm
Forum: Postbag
Topic: Andy's Postbag and random ebay links
Replies: 87
Views: 1694

Re: Andy's Postbag and random ebay links

Directing the output of one of those little modules sounds like a much easier task. I wonder if I could re-purpose a microwave oven waveguide. Given that the wavelength of the microwave is roughly twice that of the nominal wavelength of the module (12cm or so compared with 5.6cm or thereabouts), it ...
by ahull
Fri May 26, 2017 12:27 pm
Forum: Postbag
Topic: Andy's Postbag and random ebay links
Replies: 87
Views: 1694

Re: Andy's Postbag and random ebay links

actually if your WIFI router or even better network cards with multiple antennas has those MIMO and very important CSI (nope that isn't the CSI drama on TV, CSI stands for Channel State Information), you could probably use that as your radar http://pdcc.ntu.edu.sg/wands/Atheros/ http://pdcc.ntu.edu...
by ahull
Fri May 26, 2017 11:04 am
Forum: General discussion
Topic: Should I change the bootloader to use the Boot1 jumper as the DFU mode lock "button"
Replies: 6
Views: 60

Re: Should I change the bootloader to use the Boot1 jumper as the DFU mode lock "button"

Can we make this a compile time option, so if you want it, you select it, but for most bootloaders it is not on by default?
by ahull
Fri May 26, 2017 11:00 am
Forum: Postbag
Topic: Andy's Postbag and random ebay links
Replies: 87
Views: 1694

Re: Andy's Postbag and random ebay links

RogerClark wrote:I'll let you know when mine arrive.


Likewise. I decided that four was a good round number, since I'll probably blow at least two of them up while experimenting. :D
by ahull
Fri May 26, 2017 10:27 am
Forum: Postbag
Topic: Andy's Postbag and random ebay links
Replies: 87
Views: 1694

Re: Andy's Postbag and random ebay links

This is interesting -> http://tech.scargill.net/microwave-for-the-weekend/ If you want to do something clever, the 16 pin logic chip – I stuck a scope on it and pin 12 gives off some interesting analog stuff! Based on the datasheet that is presumably the 2nd stage amplification output of the doplar ...
by ahull
Fri May 26, 2017 10:16 am
Forum: Postbag
Topic: Andy's Postbag and random ebay links
Replies: 87
Views: 1694

Re: Andy's Postbag and random ebay links

Strangely enough I was just thinking, I wonder what the best way to focus one of these would be. I was going to build a tuned wave guide out of fr4, but a sat dish might be simpler and easier to come by, especially since the exact frequency these things operate on appears to be a movable feast. Mayb...
by ahull
Fri May 26, 2017 9:01 am
Forum: Postbag
Topic: Andy's Postbag and random ebay links
Replies: 87
Views: 1694

Re: Andy's Postbag and random ebay links

Nice.. that part looks familiar. FgdXRLjYkc4 Look around the 7:54 mark. I don't know what the range of them is, nor whether we can extract the speed of the target from them, but they could be very useful for switching on lighting and other loads, in response to movement. I notice that they are consi...

Go to advanced search