The Hantek DSO8060 digital oscilloscope

I’ve just received a Hantek DSO8060 digital oscilloscope. This is a dual channel 60MHz scope with a 320×240 display. Samples are 8bit. There are various mathematical functions that can be applied to the signal, notably an FFT. It is also a digital multimeter that measures A,V,R, Diodes and Capacitors. It also has a built in 25MHz arbitrary function generator. There is a USB port for attaching a storage device or connecting to a PC. It comes with a bag, two 10/1x probes, software for Windows, multimeter leads, a coax cable and a good instruction booklet. Here is the scope:

Hantek DSO8060

The screen can be saved to a .bmp file. Here is an example: this is measuring the output of a 416Hz triangle wave signal from a Droid X running my “AudioTool” application:

AudioTool output: signal and FFT on the DSO8060

This also shows the FFT (in blue). There are cursors which can be used to measure features of the channel signals or the mathematical functions, manually or automatically.

Overall, I am extremely impressed so far. The operation is very straightforward and intuitive. i shall be comparing it to my benchtop Tektronix 7844 in the next few days.

A couple of things I haven’t been able to work out: can the FFT data be averaged (the time domain signal certainly can), and how to change the vertical (dB) scale for the FFT.

AdMob

For fun, I thought I would use the AdMob api to include an advert banner in my freeware “Metaloid” application that’s available on Android Market. This is a little banner that sits, rather unobtrusively, above the main screen (see the Figure below).

The Metaloid Field Detector application on Android Market

The Metaloid application has about 20,000 downloads of which 31% are still installed, so about 6,200 active users. The AdMob idea is that you get revenue every time somebody clicks on an advert. Since adding this “feature” (I use the word cautiously), I have earned a grand total of $3.50 for a total of around 80 clicks on 117,000 adverts shown. I shall buy myself a Double Tall Mocha.

Here is the breakdown by day:

WordPress for Android

… seems like a good idea. Let’s see if it works.

Why I Like Google Android

Android is so easy to write little applications for, and is a delight if you are a Java fan! With the Android Eclipse plug in and the decent emulator provided, and the easy integration with the phone itself, the whole package is just convenient and efficient.

To take advantage of some of the new features in the latest Android SDK (1.5 “Cupcake”) I decided to flash my Google G1 Developer phone to the new release, earlier this week.

Since my phone was running 1.0, I needed to do this in two steps: first upgrade to 1.1, and then upgrade to 1.5. (I tried going directly to from 1.0 to 1.5, but it proved impossible – although it’s not clear why).

The instructions I used are here:

HTC – Support – Flashing your Android Dev Phone with a Factory System Image

The first step is to place the new radio image on the sdcard in the phone, using “adp push” from the desktop. Then the phone is rebooted into the management console, and the new image installed. Then the new system image is pushed to the phone, and installed in the same way.

This all went without a hitch, after I realised that the phone should not be mounted as a USB storage device during the process (otherwise the adp push commands to send the files to the sdcard from the desktop will fail with “no permission”).

I was surprised to find, after the upgrade, that all my installed application were still there, which was uber-cool.

Following the upgrade, yesterday I tinkered around with the Sensor API in the G1. In particular I was interested in the accelerometer, which provides real time measurement of acceleration in all three axes of the phone. It appears to be quite accurate. There are three or four built in interrogation rates for the sensor – I used “Normal”, as I was interested in making a seismometer, which doesn’t need very fast rates (I think the fastest is around 20ms per sample).

Over one lunchhour I was easily able to make the little app shown at the start of this post, and deploy it on the G1. It emulates a pen chart recorder, and shows three pens that plot the acceleration in X, Y and Z. The lines move from right to left. At the bottom of the screen is printed the latest measurement: time since start and X,Y,Z values.

Amazon: DENIED!

I had an idea for a nifty application for the Google G1 Android cellphone. I needed to use Amazon Web Services as part of the implementation, so I asked their permission (their AWS agreement is quite specific that permission is needed to develop for handheld devices).

Here is their reply:

Hello Cogshifter,

Thank you for your recent inquiry about developing a mobile application using Amazon Associates Web Services. At this time Amazon is not generally allowing the use of Amazon Associates Web Services for mobile device applications, and we are not prepared to approve your request to develop the service you outline below.

We thank you for your interest in Amazon.

Regards,

Amazon Web Services

http://aws.amazon.com

Which is a bummer, really.

Ow!

On Sunday morning I awoke from a dream in which epiphany was fiddling around with my private parts, under the table. I mean, my private parts were under the table: epiphany was seated at the table, next to me. In the dream I was a little dismayed (as I would be in RL), in case somebody noticed. This was almost certainly prompted by a “Curb Your Enthusiasm” episode in which Larry meets a fellatio specialist, goes out to dinner with her, and proceeds to put far too much hot sauce on his taco. I will remain vague about the connection. Well, whether that was the cause I don’t know, but on awaking I felt like I’d been sleeping in a straightjacket, with one arm tied behind my back. More specifically, I have an owie in my chest muscles that took the edge off my day yesterday, and is doing so today. I daren’t sneeze, for example, because it feels like an Alien might emerge from my chest cavity if I do so.

Please send telepathic hugs, Tiger Balm, unctuents, ointments, unguents, massage fingers, rare extracts of palm oil, and medicinal boobies in my direction.

In other news (as they say), I have ordered one of these:

Pocket Ghost

Last night I uploaded my new application “Pocket Ghost” to Handango. I wonder if anyone will buy it? Any self-respecting Ghost Hunter should have a copy, in my opinion. And it’s only $2.99. A bargain at ten times the price. Yeh, right.

The principle is quite simple, really. Paranormal and supernatural activity is often evidenced by the existence of very high or low frequency sounds, which we have a hard time hearing, but which animals, for example, detect easily. So your dog goes bananas when there’s a ghost in the room. The Pocket Ghost uses a pocket pc’s microphone to detect sub and super-sonic sound waves, and compares their level with the sonic ambient noise, and from that produces a measurement of how much more sub/super sonic activity there is compared with audible sound. If there’s a lot, then there is likely to be a ghost about, or some other supernatural activity. Or there may be a heavy truck rumbling past the house, or someone may be blowing a dog whistle nearby. Either way, you get a high reading for the ParaNormal Quotient (PNQ) on the Pocket Ghost display.

If you are on my Friends List and want a copy of Pocket Ghost let me know: I’m keen to get feedback from “in the field”. I’m especially interested if you routinely feel strange “presences” around you (other than your co-workers or spousage).

It’s tomorrow

No time for any decent LJ entry this evening: too busy making some final tweaks to my Pocket PC software, and I’ve only just finished.