Tjilpi

ATTEMPTED FORGERY. TINTIN INVESTIGATES.

 

Since Capt. Haddock sent his telegram, our intrepid reporter Tintin has arrived in Alice Springs and has already discoverd an amateurish attempt to forge an Xtalman masterpiece.  On the left is what appears to be a circuit diagram of a Band Pass Filter, but in reality it is a Foo Forgery. Tintin first noticed that the fingers bore a suspicious resemblance to resistors and then that the nose is really an electrolytic capacitor with the eyes simply being the symbols for positive and negative.  The hair of course is an inductor or coil. Tintin, Tjilpi and Xtalman have now joined forces in the search for Foo.  Tjilpi has pointed out to his famous friends that there is one thing missing in this crude attempt at imitation, and that is it is not signed with Xtalmans imprimateur of ©®™ with 8192 bit encryption.  Investigations continue.

READ ALL ABOUT IT: FOO HITS AND RUNS AGAIN!

ALICE SPRINGS Thursday 26 January 2012: Yet another graffito has appeared on the Town Library Wall.  Police suspect Foo, the despised mastermind behind many such defacings, to be once again behind this senseless act of vandalism. Northern Territory Police Commander Bruce Oz announced the formation of a Special Foo Unit which will be set up as soon as his operational staff are able to get through the crowds of flag waving Australians who have gathered to demonstrate against this artistic barbarity.  Commander Oz said that he had already been in consultation with XTALMAN who was prepared to assist, at any time, in the hunt for Foo. [By our Staff Reporter]

Xtalman Adds Capacity

For those unfamiliar with the Primitive Line Circuit Diagram art school, Xtal is often used as an abbreviation for Crystal.  One art critic suggested that Tjilpi's original lino cut masterpiece had something of the appeal of Mr Magoo or Foo, if the image were rotated 90 degrees counter clockwise.  While appreciating this reference, Tjilpi prefers the name Xtalman.

Crystal Radio Sets, the making of which was a popular hobby in the 1930s, used a crystal of galena - lead sulphide - the ore from which lead is obtained, as a detector, or what is now known as a diode, to demodulate the audio signal carried by an amplitude modulated [AM] carrier wave.  A "cats whisker" made of metal wire, wound into a coil with a probing tip, was moved around on the crystal of galena until a 'hot spot' was found and a station was heard through the headphones: seen on the right of the diagram looking reminiscent of "Foo" looking over a fence.  On the right of the top line is a left-pointing triangle with a rectangular block beside it. This is the symbol for a diode - a piece of electronic trickery originally made using the element Germanium - which replaced the galena crystal.  Even when a Germanium diode is used in place of a piece of galena - the radio - which functions without batteries as it only needs the energy gathered by its antenna, is still known as a Crystal Set. A simple radio such as this will receive many stations at once, as it has no means of selecting one from the other.  In order to make such a radio selective, a tuned circuit is added to pick out stations operating on different frequencies.  The addition of a capacitor, represented by the bright white lines with horizontal bars mid-left circuit, is one way of doing this, and that is why Xtalman has "added capacity" to his original form, which may be seen in a post below. 

Rapid changes in technology have not only seen galena suitable for use in crystal sets difficult to obtain, but Germanium diodes are equally hard to find. Tjilpi has fond memories of making crystal set radios with both types of detector when he was a weeaye of about twelve summers, so if anybody is having difficulty wondering what he would like for his birthday: there's a hint.

Déjà vu

It suddenly came back to me.  There I was sitting at the Command and Control Station in my Bunker on the Old Eastside of town, looking out at my sparkling blue swimming pool, when a Tree Martin came in from the south, banked and dived steeply to the east to do a "touch and go" on the surface of the water before repeating the trick by completing another circuit and then disappearing.

 I've never understood what they are doing. I've wondered about their being so thirsty that they will drink chlorinated swimming pool water, or whether they are picking up insects which are floating on the surface. 

I first saw the phenomenon in January 1979, through the south facing window of my ground floor single room at the Professional Officers Quarters at the Alice Springs Hospital.  The large ceiling to floor window, seen in the faded photo above, looked out on the hospital swimming pool, from what I always regarded as the best room in the house.  Then [notice there is no need to say, 'back then' as 1979 gives that game away], the birds repeated their "touch and goes" numerous times.  January in 1979 was very hot.  It's been 42°C here [now] the last couple of days, but I remember a run of 14 days all of which were over 40°C in January '79.

There must be something special about being in an air conditioned room, with a south facing window looking over a swimming pool watching Tree Martins do their tricks in the heat of January.  I'll have to think more on it.

Tjilpi Turns to Art

Tjilpi's bout of writers block has not resolved, so he decided to turn his hand to art.  On the left is one of his early Linocuts. 

It belongs to the School known as Primitive Line Linocuts. 

This Linocut is outstanding in "real life". Unfortunately, the reproduction process used by the printers of the photo has turned what is in fact a fantastic blood red background into a muddy orange, and they have also horizontally "flipped" the whole image 180 degrees to conform with normal circuit diagram orientation.  Apparently the printers weren't aware that Tjilpi fully intended the image to be 180 degrees out of whack horizontally when he cut the lino prior to pressing the image.  However, whichever way you look at it, this work is a masterpiece.

Tjilpi's pieces will be on sale in the Todd Street Mall when the Alice Springs Markets recommence operation in a month or so.  Critics are suggesting that this early work will command a four figure sum. When asked about his attitude to the Dot Painting School, Tjilpi gruffly replied that it really wasn't very difficult to connect the dots to make lines, and he wondered why people hadn't thought of doing that before he did.

Writer's Block ...

It came, it saw, it conquered.

I hope it goes away.

'Tis the Season ...

This morning I looked at my Google calendar and saw that for the next two weeks I have no appointments with any of my minders.  That must mean I am getting better.  I’m sure it has nothing to do with the fact that all my minders are going away for Christmas.

I’m not going anywhere this Christmas. I’m not yet up to that, but I am going to have traditional “turkey” and Christmas pudding.  That is despite the fact that I think the guff about traditional turkey is a lot of old gobblers.  The tradition I grew up with was watching Ernie, my maternal grandfather, chop the heads off two chooks which he had brought in from the chook run in the backyard.  He used to do the chopping underneath the high blocked house at 6 Thomas Street, Maryborough.  Ernie held each chook by the legs so that their head lay on the chopping block which was normally used for making wooden chips to start the fire in the wood cooking stove upstairs.  Down came the axe and he would immediately release the bird with blood spurting from its carotid and vertebral arteries. Sometimes their bodies would run upright for a metre or two before falling over. Then came a dousing in boiling water taken from the soot blackened copper which was used for washing clothes each Monday.  The boiling water loosened the feathers making it easier to pluck them.  All the gorey stuff was done on Christmas Eve, and visions of headless chooks were merely a distant memory by the time I was served up a chicken drum stick for Christmas dinner the next day.

Turkey is a bird native to North America.  When did it become traditional here?  Trad or not – I’ve got a kilo of frozen turkey breast in my freezer.  Now that is a bit of a white elephant, that chest freezer.  I bought it when I set my sights on the “ageing bachelor life”.  I could see myself cooking up a storm and then freezing separate packages of yummy pre-cooked dinners for one.  Mum had a chest freezer which she used to fill with stews and casseroles, so that Dad wouldn’t starve if she were to go away somewhere.  I was following that pattern.  Well, I thought I was following that pattern until I discovered that the freezer built into the bottom of my fridge is sufficient for my purposes. After all, around here, I’m both the cook and the starvee, if the cook goes on strike.  So I learned that my freezing capability is excess to requirements.  The one kilo of Steggles Frozen Turkey Breast bought over a year ago at a bargain price, will be coming out of the freezer, and then I’ll be able to sell it in a lawn sale in the New Year.  [No. Silly. I’m not planning to sell the turkey breast in a lawn sale.]

I’ve got lots of things to sell in my lawn sale. A Leitz microscope, a no-brand 20 MegaHertz oscilloscope, a high end Epson 4990 scanner,  multiple small gas bottles for camping, a safari tent, fishing rods and reels, assorted fishing accoutrements, a box trailer, books, tapes, and CDs.  I could sell a few of the 24 radios I have counted as being in my possession but I need each and every one of those.  Oh, make that 27.  There are kits for a one valve AM receiver, a crystal set, and an FM transmitter all yet to be built.

That should give me something to do on Boxing Day.

The Man Said: Give This a Go

This morning I was reading an article called "The Ins and Outs of a Sound Card". The article originally appeared in a well known Ham Radio publication called QST, in October 2003. 

Computer sound cards are a very important part of my new hobby: learning about a digital code, which is sent by radio from computer to computer, using a technique called Phase Shift Keying, or PSK.

For the past week I have been listening to the high pitched warble of PSK transmissions, and I have been able to "see" the transmissions as vertical yellow lines falling, waterfall like, down the blue screen seen above. There are two vertical yellow "lines" visible.

At the very top left of the screen shot is my ham call sign: VK8KMD.  Below that are some gray control buttons and below that in the larger white area there is some text which looks quite garbled, but which makes a good deal of sense once you know how to read it! 

Tonight, I heard a strong signal and saw the callsign, BV100 arrive several times.  Now BV100 is an unusual call sign, but the signal was so strong that I decided it was time to follow the advice of the man who wrote the article on Sound Cards.

As yet I haven't wired the sound card in my computer to my ham radio transmitter; but I have hooked the ham radio receiver to the computer sound card so I have been able to see and hear incoming signals for some days, but I have not sent any.

The smaller white box, underneath the scrambled text, is where text to be transmitted is typed.  There is nothing in that box, as I managed to "clear" it by hitting the wrong control button before taking the screen shot. However, I did type my call sign several times before clicking my mouse on the small box labelled TX, for Transmit.

Imagine my surprise and the thrill I got when I saw my call sign appear in the upper white box.  It was acknowledgement from BV100 that I had been heard.  On the 6th and 7th lines you can see GREETING TO . STRALIA.

PSK is a like that. It requires the granting of a certain degree of latitude, combined with a fair helping of magnanimity of spirit!

The 4th line is my transmission saying NICE TO MEET YOU. SRI OM I HAVE NO INTERFACE. USING MIC ON TX HELD TO COMPUTER SPEAKER.

SRI OM is ham talk for "sorry old man"! "MIC" is the accepted way of spelling what I pronounce as "Mike".

After our short exchange I looked for BV100 on the Web and found out that I had been talking to Taiwan.  BV100 is a special station set up to celebrate Taiwan's Centennial! There is more information about that here: Taiwan Centennial

The person who was operating the BV100 station and sending me PSK messages was Yohn Wang whose personal call sign is BX5AF.  You can see that in the 5th line.

I am very glad I followed the advice of the man who writes about Sound Cards.

He said: Give this a go.

I did.

It worked.

Man on a Mission

A while back I bought a new baby computer as I thought I was going travelling.  The baby computer is only 26 cms wide or 10¼" in the old money.  At the same time I bought a prepaid wireless modem so that I could connect to the internet while travelling.  By travelling, I mean the kind of journey one has to make when one lives in the middle of a continent where most high-tech services are located on the coast. The picture I had in mind was of myself travelling to a hospital in the big smoke to have some kind of surgery on one of the few conditions this gray bearded tjilpi has acquired.  I wasn't sure which condition I was going to opt for being treated first but I thought something would had to be done. I envisioned myself painfully, but paradoxically comfortably ensconced in a hospital bed, in the big smoke, with my internet access intact, even if my dignity weren't.  Have you tried wearing a hospital gown lately? I mean one of those which do up at the back and inevitably leave a wide open gap?

So, with thoughts of gaps in the back of gowns hovering incessantly, I decided I didn't need to go travelling to faraway hospitals and instead I would stay at home, as I have a few missions to undertake right here.

Not going to hospital means that I can concentrate on the important things in life - such as getting my ham radio hooked up to a computer and my baby computer hooked to the internet via landline rather than via its prepaid modem.  I want to have a go at communicating with other hams using PSK31.  PSK31 is short for Phase Shift Keying at 31 Baud.  Don't worry - I didn't know that either, until the middle of last week.  PSK31 became my obsession last Wednesday night when  I stayed up all night after downloading some free software and got to watch typing inch its way across my computer screen after it had been sent through the ether by hams from all four corners of the globe.  PSK31 is a bit like radio teletype of yore.  Telegrams used to be sent that way when I was a kid. 

I can hear somebody saying: It's easy to download typing from the Internet - what's so exciting about PSK31? Well, a simple answer is that it's the kind of thing which allows one to understand a little more about how it is possible to download typing from the internet.  Using PSK31 is something like catching an email out of thin air, and then being able to reply to the person who sent it. So there!

In the photo [above, on the left] baby is sitting precariously atop a cassette radio CD player. I have written about that set before, and yes, I have yet to install the new rubber bands on its tape deck.  Hey, even if I am not working at present, there still isn't enough time in a single day to get everything done which needs doing.  That's why I have to pull all-nighters just to keep up with myself.

The immediate mission with baby was to stop using the credit on its prepaid modem and swap to using the excess internet capacity I have on the landline. My desktop/laptop connects to the internet via the phone line and Teltstra allows me 12 Gigs per month internet access on that. I only ever use about 6 Gigs of the 12 Gigs so I figured that baby should be using up the spare 6. They will only end up in the bit bucket at Telstra if I don't use them.  Imagine, I said to my self: "Self, imagine what it would be like if you got baby to stream music from the internet and put its output through the same amplifier you use to amplify signals from records on the turntable.  Now that you have the turntable firmly wired up to the amp, wouldn't it be nifty to add another source of music?  It wouldn't be a clash of technologies: just an apposition of the old and the new."

So I got my self to work, and after about 48 hours of fiddling with the mysteries of WiFi networking, I managed to get baby to talk to the desktop/laptop and the desktop/laptop to talk to the internet on baby's behalf. From baby's point of view, baby is talking directly to the internet and now brings me the latest technology in getting ones choice of music into the house.  I simply grab free stuff off the web from a place called Grooveshark. If I want to listen to Slim Dusty, I type 'Slim Dusty'. If I want to listen to Elgar's Cello Concerto in E minor, op 85 played by Jacqueline Du Pre, I type that. Baby finds the music and streams it into the amp.

No longer do I need bits of musical "stuff" in the house - you know, the kinds of things which need sorting, cleaning and general molly-coddling.  Gone are the days of fussing with records, record sleeves and covers, tapes and breakages, CDs with their fiddly containers and scratchable surface. 

I learned a lot by setting up the WiFi network myself. And I saved a packet as well. Salesmen were pointing me in the direction of $600 worth of wireless adapters and wireless modem routers to do what I finally ended up doing without any add-ons. I was so happy when I got my wireless network going at 2 am I just had to turn up the volume on the amp.  Elgar at 2 am can be very striking.  I hope I didn't disturb the dog next door too much.

This morning I took things one step further.  Baby came to bed with me last night, and this morning I was able to watch Doc Martin streaming in on TV from the ABCs iView.  I like watching Doc Martin.  I think I need to adopt more of his attitude.  Although he doesn't give me the impression that he would have any interest in PSK31 or streaming music and TV into the bedroom.  Maybe he would be less grumpy if he were on a mission too!

It's only temporary

My father told me that Ernie, my maternal grandfather, was fond of building small structures or making alterations around the house and then saying: "It's only temporary."  And twenty years later it was still temporary.

So, with that in mind, I'll have to do something definitive about the temporary arrangement I made on Sunday morning. 

After my father died my daughter Julia put dibs on his Pioneer PL 335 turntable which eventually found its way from Maryborough in Queensland to my house here in Central Australia.  Some years ago Julia was involved in obtaining a 1982 model Sharp Optonica Stereo Amp, which came her way via the parents of one of her friends.  All the parents asked for in return for the Stereo Amp, was that I convert five of their vinyl records into CDs. 

That job has yet to be done.  There has been a temporary delay.

My father's turntable, with wires covering the lid,  is in the photo above.  The Stereo Amp is also partly seen on the left under the watchful eyes of Tin Tin and Snowy. [Click on the photo to enlarge it.]

Saturday night was the time for me to make an 'interconnect', as we audiophiles say, between the turntable and the Stereo Amp.  On the right is a photo of a German 8 Pin DIN plug of the type which came with the Stereo Amp. Its role is to plug into the rear of the Amp in order to connect a turntable. However, the cable attached to the DIN plug I have, has been cut and there is no connector at the cut end.  How the cable was connected to its original turntable I will never know, but I did open the outer covering of the cable to find that it contains 7 wires.  

Below on the left is a photo of two RCA plugs of the type coming from my father's turntable. Each RCA plug houses two wires and there is also a fifth wire to connect the earth of the turntable to the earth of the Stereo Amp.

My immediate problem was: How do I connect the 5 wires from the turntable to the 7 wires going into the Amp?

In search of information, I joined an audiophile forum on the Web, and by doing so gained immediate cachet as an Audiophile myself. That accounts for the way I am now able to speak so authoritatively on this subject. It was on the forum that I learned that the correct terminology for what I was doing was making an 'interconnect' and not simply making a connection.  However, I was not able to find anything to help me work out how to connect 5 wires to 7; but by 2 am, after a lot of Googling,  I had come up with what I thought were 'the goods' and decided to leave making the interconnect until Sunday morning.

For non-audiophiles, I think I should expand a little on the subject at hand.  The trouble with a turntable is that it will turn records, but it won't 'play' them.  Modern record players are nothing like the coiled-spring driven gramophones of my childhood. Those could be wound up by turning a crank handle. Pure mechanical motion generated the sound of music.  Not a single electronic component could be found in something like the Victrola shown on the right.  My grandparents had two such portable gramophones which I began playing with at the age of eight.  It was magic to sit on the front verandah of their house, playing old 78s, while pretending to imitate the dog who never tired of listening to "His Masters Voice".

Around a month ago I took my father's turntable from its storage spot and discovered that the rubber belt which drives the turntable had perished.  I found a source of replacement belts in the US. Two belts cost me less than the price of the postage to get them here! After fitting a new belt it was time to see what electronic trickery was needed to get the turntable to produce music.

By way of background information, I'll let you know that around the time I was courting Julia's mother I was building my first stereo amplifier from a kit.  It was a Playmaster 60/60.  One part of building that stereo amp involved constructing a Phono Pre Amp.  I never used the Phono Pre Amp on the now defunct Playmaster 60/60.  The reason for that was that I had eschewed all vinyl, and had transitioned my allegience to an all cassette music collection.  A Phono Pre Amp is only required to amplify the tiny electrical voltages generated by the diamond stylus vibrating in the grooves cut in the vinyl of a record on a phonograph.  A view of vinyl grooves, magnified 1,000 times is on the left. The stylus is attached to a thin piece of metal called a cantilever which in turns moves a tiny magnet inside a field of coils. The movement of the magnet within the coils only generates a few thousandths of a volt.

Consequently this tiny voltage needs to be amplified to be useful.  Amplification is a tricky business.  The aim is to go slowly, adding a little bit at a time. If there is too much amplification at the beginning of a cascade of amplifiers, distortion can set in and mess up ones listening pleasure. 

My father's last stereo amplifier didn't have a Phono Pre Amp.  He wanted something which would play CDs, casette tapes and the radio, and ended up with a space age looking 'ghetto blaster' sans Phono Pre Amp.  He bought a Pre Amp separately.  It came in a plastic box with the right connections to allow him to connect the turntable to the space age boom-box ghetto-blaster and so allow him to listen to his extensvie vinyl collection. That 'set up' worked quite well.  Fortunately for me the Stereo Amp I now have has a built in Phono Pre Amp, just as my Playmaster 60/60 did.  But unfortunately for me I had to work out how to make an interconnect between different breeds of connector. Saturday nights research gave me some hope. However, I still felt I was entering tiger country by trying to connect the 5 wires from the turntable to the 7 wires from the DIN cable.  On Saturday night I had studied as many schematics as I could find on theWeb. I've put one example on the right. 

Even after I thought I knew what was going on, I wasn't absolutely sure that I could make the 'interconnect' work. I took some comfort knowing that if I did get electrocuted, it would be with only a few thousandths of a volt. After a lot of fiddling, I found that a couple of wires from the end of the 7 wire cable seemed to be redundant and so I left them waving in the breeze. I found the correct 5 wires out of the 7 available purely by chance,  combined with a little knowledge. The interconnect works.

On the left is a close up of the temporary connections I made from the two RCA plugs to the bare wire ends of most of the wires from the DIN Plug cable.  [Click to see the exquisite detail.]

Last Christmas Julia gave me a vinyl copy of Chris Rea's On The Beach. I had listened to the cassette tape of the same albumn over and over when putting the Playmaster 60/60 together. Each channel of a stereo amp is usually physically and electrically separate from its mate, and apart from the fact that I liked Chris Rea's music, each channel of the Playmaster 60/60 needed to be aligned with the other so that each channel would emit the same volume when the single volume knob on the front of the amp case was rotated. For some reason that exercise seemed to take me forever, and On the Beach was played repeatedly as I tweaked variable resistors adjusting the current flow in the right and left channels.  On Sunday morning it was a great thrill to hear that same music coming from the vinyl record Julia had given me, as it rotated on my father's turntable.

But now I have to deal with the 'ownership' of the Stereo Amp. Now that I have a means of playing vinyl records I'll have to do something about the five records which came with the Stereo Amp.  They still need to be converted into CDs for the original owners, the parents of Julia's friend. 

And that means that I'll have to do something about my temporary arrangement.  The green, white, and red alligator clips are sitting on top of the lid of the the turntable.  If I open the lid to put on a new record, the interconnect falls apart, and needs to be put back together.

So a permanent interconnect is required, before the whole thing sits there for too long being temporary.