So, how's the penguin?

I've been fiddling with my Pinguino board a little after the build I reported last time. I have, in fact, created a second board - this one will end up as my first Pinguino project. I would like to make a DDS signal generator, but this one needs to include a sweep function so I can more accurately measure crystal filters.

Here's the new board, you'll see that I have interfaced an LCD display, a keypad and if you look carefully you will see there is a rotary encoder there also:

The display has a really neat blue backlight, but is almost impossible to photograph:

I actually want to use a four line LCD display that I have here, I think the software needed to drive the four line display will be the same, I just wanted to start with something I am more familiar with. I am a great believer in build a bit - test a bit.

The keypad will be used for frequency entry, and I have that working OK - I wrote a test program to simply display the keypad entry on the LCD and that's working fine. The shaft encoder will be used to change the frequency steps by utilising the push click switch that's built into it and the rotary part will be tuning when in signal generation mode.

So far so good, but the DDS module I have here I used before:

http://g0mgx.blogspot.com/2011/08/dds-this-and-dds-that.html

This uses a AD9850 DDS chip, and at the time I was interested in the later AD9851 DDS but I couldn't find a way to buy the chip in anything other than the basic SMT package itself. A quick look on eBay suggests that you can now get development boards quite cheaply for this IC now so I have ordered one. It includes 6x clock multiplier on board so it should be easier to get extreme accuracy without spending a fortune on an accurate high stability high frequency clock module.

So, now I wait for a parcel from Hong Kong - why there aren't any in the UK I have no idea.

Time will tell, fun though, egh?

Penguin - you mean Pinguino!

Well,

For a few days I've been playing once again with Pinguino:

http://www.pinguino.cc/

It's an IDE that simplifies programming of PICs and the one I've built uses the 18F4550 PIC from Microchip. The board I have built is detailed here:

http://wiki.pinguino.cc/index.php/PIC18F4550_Pinguino

and it looks like this:

I had quite a bit of difficulty getting the IDE to run on Windows 7; previously I managed to get it running on Linux, but with some help from the Pinguino forum users, I was pointed at this tutorial:

http://tutorial.cytron.com.my/2011/08/20/pinguino-installation-window-7/

Which has worked out just fine. The IDE is now running:

and this communicates with the board via a Bootloader that you have to program into the PIC. I accomplished this using my recent ebay purchased Olimex PIC board:

This board is directly compatible with the Microchip MPASM IDE and programming the PIC was a doddle.

Once the PIC was programmed and on-board my homebrew Pinguino I have managed to successfully download and run an initial test program to flash an LED. Not much to show for it, but good progress!

I'm planning to play some more with DDS and some other homebrew ideas I have; all of which will be PIC based.

Watch this space!

Can we handle the power?

Well,

The ATU that I am making for Vince has finally neared completed. My mate Paul completed the drilling of the metalwork for me; after my recent experience with drill bits I decided to let someone who knows what they are doing have a go!

So here are some pics of the nearly finished article:

The quality front panel labels are courtesy of my recent e-Bay purchase of a Brother label printer:

The problem we have now is that the turns counter we bought has a metal front panel piece. This (which I thought was plastic) is connected directly to the metal shaft which in turn is coupled to the metal parts of the roller coaster and is therefore at full RF potential. This is dodgy because we don't want that potential near the user and also because the front panel itself is at ground; the screws holding the turns counter to the front panel are actually causing a short circuit.

An initial attempt at getting past this problem by using some isolating washers (the kind of thing you would use to isolate a TO3 transistor from a heatsync) between the screws and the two other metal bits has resulted in a rather spectacular light show at about 40-50 watts. Clearly no good, and even if it worked electricaly, the metal part of the turns counter would still be at full RF potential, dead ATU  users makes for little or no repeat business, so this is no use whatsoever!

I'm going to get my aforementioned chum Paul to try and make be a plastic shaft coupler... we will have to see how that works out.

You can see the offending article at the very top centre of this picture, it's all at full RF potential:

To finish, here's a recent picture of the Geddy cat:

Al good fun though, egh?

How did that happen then?

Well,

I've been trying to make an ATU for my mate Vince, G0ORC. We have been toying with the idea for some time, but have finally decided to cannibalise an old CAP Co Tuner that had a very broken turns counter. The parts have ended up inside a rack mount box and I have been slowly building these bits into a high power tuner. There are two chunky variable capacitors and a really well made roller coaster inductor:

Now, today I have been making a bracket to mount a wafer switch on, this is to be used to switch the ATU between the rig or a dummy load. Nothing complex going on here you wouldn't think.

I used a recently purchased set of drills, the result was rather astonishing:

This was a bargain set of drills from Maplin, fantastic!

I think the ATU is going to work out OK though, once I've drilled the holes I need, what do you recon?

Tuning - with less noise!

Well,

For some time I have been using an LDG Electronics AutoTuner here in the shack. It's been an OK experience and the ability to change bands and then have the tuner sense the RF frequency and auto adjust itself back to the previously stored settings for antenna and band appealed greatly. Set it up once and never touch it again - perfect!

The theory was fine, but it didn't quite work in practise. The device never quite matched the antennas correctly - I always found it necessary to tweak the automatically chosen settings and then store them manually plus on most bands I couldn't quite get a 1:1 match. My biggest concern with the unit was that the SWR reading on the tuner itself didn't ever match the readings at the radio or with the separate meter I have here. The net result was that I was tuning for the best match read by the radio, which was normally quite a miss-match according to the tuner.

Anyhow, to cut a long story short, I have purchased a MFJ roller coaster based tuner:

Looking at this picture worried me a little. There very much looks like there is a dent in the top of the unit! However it's completely invisible unless taken by a camera with a flash but I should probably consider reporting this back to the supplier.

Anyhow, using the device as a tuner seems extremely easy. MFJ tend to have a bad reputation and are often called "Mighty Fine Junk"; however, my experience is all good. This tuner does exactly what is says on the tin. I've completed some tuning charts which I will try and print out and place somewhere near the unit itself in the shack.

The cat has taken on a whole new degree of madness; he has now taken to sleeping in the cover of my 'scope on a high up shelf in the shack:

I'll keep you posted on the tuner, looks OK though, egh?

It must be Christmas

Well, not much going on here; just been playing Radio and generally taking things easy.

I made a visit to the post Christmas sales and came home with a laptop which is now interfaced to the FT857 via the homebrew device I was making earlier:

http://g0mgx.blogspot.com/2011/12/three-soundcards-no-you-must-be-kidding.html

That is enabling me to leave the laptop running WSPR whilst all the other electronics are shut down - except the FT857, of course.

Very neat laptop, got one of these new fangled Intel i5 processors and is running 64bit Windows 7 - all reasonably well priced and more importantly low power consumption.

I used to leave both PCs running in the shack, but more recently have taken to shutting them down - primarily to conserve power. But now I genuinely find that the shack is rather cold in a morning so I'm turning the heat on - not much of an energy saving!

The shack is looking quite tidy right now, I've even added yet more shelves to create more space in this tardis I spend my time inside:

I need to get outside and look at the Windom antenna again:

http://g0mgx.blogspot.com/2011/12/its-just-been-far-tooooo-long.html

because the SWR on the antenna is bouncing in windy conditions (again). I suspect it might just be too close to the other metal objects and when it moves around it's either touching the mast thats holding the 6m beam in the air or actually touching the antenna itself. Only time will tell.

The Geddy cat has many places he could chose to sleep; he has two proper cat beds, theres also four people beds in the house, plus a choice of sofas, chairs et cetera. He does, however, prefer to sleep on the clean washing as it waits for the ironing fairy to pop round:

Damn crazy cat!

Three Soundcards - No Problem!

Well,

following the last escapade with exploding USB soundcard devices, I purchased an alternative from a local store. This time is was a staggering £10.

I hooked it all up and everything seemed to be working fine; I made a few minor adjustments to the audio attenuation levels going into the soundcard mic input, but nothing unusual.

So now we have the shack looking like this:

And the FT-857 is happily WSPering away:

Given that its quite early on a dull winters day here in Belper, this is with the output power set at 10W:

And here, as a change from the mandatory cat picture, is my Bird of Paradise, grown by me from seed and in flower:

Fantastic, hugh?