Geekerama

Still annoyed

/ masher / 6 Comments
You know when you build a ringer circuit to drive the bells on an old rotary telephone powered by an Arduino, and you design the veroboard layout, optimising it to get the board as small as possible so it will fit in the phone, and then you spend an hour or so, carefully soldering the components into place and when you’ve finished, you sit back and admire your handiwork before you then connect it to a power supply and check that it works OK, but it doesn’t, because you realise almost immediately that you got the Gate and the Drain the wrong way round on the MOSFETS, but when you try to get them out, you can’t because the board is too densely packed underneath and even with a de-solder pump and some solder wick you can’t get the damn things out and then the tracks start to lift because you applied too much heat for much too long, so you realise that you are now just going to have to throw it away and start again?
You know when you do that?
It’s bloody annoying, isn’t it?

Buzby Nostalgia

/ masher / 9 Comments

Yesterday – May the wunth – was my birthday.

As is usual on my birthday, I bought myself a little present.

That’s it there in the photo on the left.

Ain’t it luverly?

That, my friends,  is an early 1960’s GPO Type 706, as you well know. Beautifully refurbished and fully working. Oh, you should hear her ring – proper bells!

I’d actually wanted a Type 746; y’know, the one with the improved regulator circuit. But I couldn’t find one in red. And I really wanted red.

I actually bought it for a little project I am working on, but I am just so enamoured with it, that I might just leaved it plugged in and sitting on the coffee table in the lounge.

If nothing else, it’s a conversation piece.

Project Phoenix

/ masher / 7 Comments

I was gifted a lovely little radio a while back – a Yaesu FT-270R.

It’s an old 2m model, dating back to the late eighties, I’m guessing.  As such, it lacks CTCSS capability, which limits its use somewhat.

However, there is a space inside to fit a FTS-8 subtone encoder board. And so I thought I’d fit one of these and give it a new lease of life.

Sadly though, the FTS-8 board is no longer available and secondhand ones command a hefty price tag.

What to do? Well, make one of course!

I found an elegant design on the web and built it onto a piece of veroboard. Plugging it into the radio, changed some of the available functions, so the radio obviously detected the board.

It allowed me to choose the subtone from the front panel. Excellent.

But it didn’t work.  Checking  the output with my scope, the tone just wasn’t there… or rather, it wasn’t what it should have been.

I spent ages fiddling with it, but ultimately could find nothing wrong.

And so I passed it onto Dave, who – being a clever bugger – worked out pretty quickly that the board I had built actually worked perfectly. Unfortunately, the radio didn’t. It was giving out the wrong signals to the board.

This wasn’t something that could be easily fixed – possibly a microprocessor issue. And so, I figured a workaround, that would allow the tone to be selected manually, using a combination of switches to produce the binary equivalent of the hexadecimal value that the board was looking for in the tone lookup table.

This worked perfectly and when I tested it, I was successfully able to open several different repeaters, all using different subtones.

And then I found a bug, where the tone would only change after five minutes and not whenever the PTT was keyed.  This looked to be a fault with the MCLR on the PIC… possibly damaged by putting in 7.6 volts from the radio (datasheet states that Vpp shouldn’t exceed Vcc). Not having another chip available, I made a slight mod and fitted a miniature relay, which only allowed the board to be powered when the PTT was depressed.  This seemed to work nicely and I was able to switch tones easily and on-the-fly.

So, I put a call out on a repeater. “Your audio is awful!”, I was told.   I replaced the mic ( a new one from ebay cost fifty quid! Yes, fifty quid for a 30 yr old mic!) with an old YM-47 from an FT-290 and it worked perfectly… once I had figured out the differing wiring scheme.

And so, after many weeks of working on it, on and off, it is ready to be put to use.

Not that I need another radio at the moment, so a friend is going to borrow it.

Many times I nearly gave up on it and was going to throw it away. But, I had invested a lot of time and a reasonable amount of money on it and so I wanted to see it through.

I’m pleased that it is finally finished and working… because that means I can now move onto my next project 🙂

Brain dead

/ masher / 5 Comments

This week, I have been in training.

Learning all about hydraulics and fluid dynamics.

This is a page from my workbook.

You can see where I’ve been using the Hazen-Williams Equation to work out friction losses.

Can’t you?

And today, we have been working on the Benoulli Equation to show how the speed of a fluid will increase or decrease inline with a change in it’s potential energy.

Of course,

I haven’t worked on calculations like this, since I was at college, back in the eighties, so it’s fair to say I’m struggling with it a bit. 

And whilst those around me are all using the calculator function on their phones, I have been using my trusty calculator from my college days.  It’s interesting to see that – like me – it’s not as fast at working out these big sums as its more modern counterparts.

I’m happy to admit, that I’m struggling with it all, a bit.   And even when I think I’ve done one easily and sit back smugly, it normally turns out that I have made a stupid mistake somewhere along the line, which has left me with a result that is nowhere near what it should be.

Whilst I was no Carol Vorderman, or Rachel Riley (I’ve got better legs), I was reasonably good at maths, back in the day.

Where did it all go?

I officially give up! Yet again.

/ masher / 9 Comments

Morse code is an anachronism.

Invented and used in the 1840’s, it seems somewhat out of place in today’s high-speed world, where data rates are so high that whole sentences of text can be sent in the blink of an eye.

It’s an outmoded form of communication, that just doesn’t sit well with modern  methods.

And yet… it does.

It is still used by the military – not necessarily as the main basis of contact nowadays, but certainly as a fallback, I’m sure.

And in the world of Amateur Radio, it is still a much sought-after skill amongst many.

There are plenty of amateurs out there who can do Morse.  Many of them excel at it.  And there are even some that won’t use any other method to communicate over the air.

Sadly, I’m not one of them.

I would LOVE to be able to read morse code, properly.  I can send at slow speeds and I can read it at very slow speeds. Very slow. Very, very slow. Reading is the hard part.

Rather like learning a new language (and ostensibly, that’s what it is), there are many different methods for learning it. Over the years I have tried reading books (Duh!); listening to tapes and listening to other operators sending. I have tried several PC programs and mobile phone apps. I have built machines for practicing with (see picture above), eventually taking them apart and using the bits for another project, because I was getting nowhere.

Frustratingly, in my teens, I did learn how to read and send, and could do so at about five or six words a minute.  If only I’d kept it up.

Similarly, I used to be able to parlez francais to a reasonable degree.

But I allowed them both to lapse and nowadays I struggle to learn either.

And it really annoys me.

I’ll admit that this is partially down to commitment. I don’t seem to have the time nowadays to study for such things.

And the inclination. That’s kind of gone too: I want to learn it, but I don’t want to put in the effort.  Like the rest of the MTV generation (yes, I think I just about fall into that category) and, as Freddie Mercury sang: “I want it all and I want it now”.

And so, after several months of “giving it another go”, I have hung up my headphones.

Again.

For the last time.

That’s it! I have resigned myself to the fact that morse code will forever evade me.

No more, will I try learning and decyphering that strange sound of dits and dahs pouring from my radio speaker.

No more, will I spend hours in the car listening to an 800Hz tone beeping out letters of the alphabet to me.

No more will I drive the family mad, as I sit in my room badly tapping away at a morse key.

No more, will I… who am I kidding? Give it three months and I’ll be back at it for another half-hearted attempt.

Guilty, As Charged

/ masher / 6 Comments

I do wonder about myself sometimes!

Last night, I built a wireless charger for my phone.

It took about a week for the bits to arrive from China, and then about an hour for me to fit it into a suitable container that would act as a charging pad – I used the lid off of a jar of decaffeinated coffee.

My schoolboy error?

My phone doesn’t do wireless charging!

Oh well, at least it was quick and cheap. And it hasn’t gone to waste, as Daighter’s phone does have that functionality, so she has already snaffled it away to join the junk on her bedside table.

*Must do better research next time*

Good and bad

/ masher / 10 Comments

I’ve had a torrid time of it this week, on the motorways.  I know I often joke about it, but I’m starting to wonder whether being able to bring traffic to a standstill, merely by being on the same road, really is my super power… as rubbish as that would be.

My journey home from work on Monday had an extra hour added to it, when an accident on the M40 reduced the motorway from three lanes down to one. During rush hour.

Likewise on Tuesday, an accident on the M1 at Hemel closed three of the four lanes during rush hour, adding ninety minutes onto my journey home. Ninety minutes! And when we finally got moving and got past the accident, there was hardly anything to see. If I’ve been made to wait that long in the traffic, I want to see a reason for it, carnage even, not just a BMW with it’s front bumper hanging off!

Wednesday. Don’t get me started on Wednesday! I had to go to Swindon for a couple of meetings and so left half an hour earlier than normal. We suddenly ground to a halt about 2 miles from J18 on the M25. And we just sat there. And sat there. Eventually we inched along and I could see that all the lanes had been closed, due to an accident and the police were turning vehicles round and sending them back up the motorway. We all got diverted through Rickmansworth. Can you imagine four lanes of motorway traffic driving through Rickmansworth? It wasn’t particularly quick, I can tell you! I eventually arrived in Swindon – having completely missed my morning meeting – after five and a quarter hours. A journey that normally takes about two and a half.   I left as soon as I could, following my afternoon meeting, but was thwarted once again when an accident on the M4 slowed us all down. “Long Delays Between J12 and J10” threatened the overhead signage. My heart sank and I looked to my satnav for advice. “Avoid this bit of the motorway and go through Reading”, it said. Sort of. No way! I’ve been caught like that before. Reading at rush hour? It’d be a nightmare.  And yet…   If I could just get to the A329… Inexplicably – and possibly because I still had the morning’s motorway horror still in my head, I found myself taking the slip road at J12 and heading to Reading on the A4.  I was right: it WAS a nightmare.  Four hours after leaving Swindon, I arrived home.

Thursday wasn’t so bad, save for a bit of a hold up on the 413 Denham Road in the morning.

And then yesterday, Friday – when I can normally work from home – I had to go into work for a meeting. I had a lovely journey in. Friday mornings are definitely the best time for driving on the motorways.  Friday afternoons, not so.  My journey home was again lengthened by some numpty who doesn’t know how to drive properly on the motorway, ramming into the back of another vehicle and causing a huge tailback on the M1.

If only everyone was as good a driver as what I am, there would be no accidents. They all drive too fast and too close. Unlike Miss Daisy here.

But today has been good: a leisurely drive to our local annual ham radio rally with a couple of mates.

Good weather.

Plenty to see.

A couple of bargains.

Meeting up with more friends.

And an ice-cream.

A perfect Sunday.

Hit It!

/ masher / 14 Comments

For ages – and just for the fun of it – I’ve wanted to build a Batak.

I think that’s short for Button ATtAcK.

I think.

Basically, it’s a reaction game: a button lights up and you press it, and then another lights and you press that, and then anoth… well, you get the idea.

All against the clock.

They are used widely in Formula 1, I believe, to help the drivers improve their reaction times. It takes speed, hand-to-eye co-ordination and good peripheral vision.

I’ve always thought that building one wouldn’t be too difficult, but my programming skills are THAT rubbish, that I could never quite figure out how to do it.

And then I spotted a project to build one, on the Instructables site, by a clever chap called R0RSCHACH and I have pretty much copied his design exactly, but then added a few little bits so that it can either run off of a 12V battery or can be plugged into the mains.

OK, it’s not as impressive as a proper Batak, I suppose, but it does the job and it only cost me about fifty quid to build. Proper ones go for hundreds or can be hired for several hundred a day!

It’s been a lot of fun building it and I’ve learnt quite a lot too  -though my programming skills are still rubbish.   My woodworking skills aren’t much better and the wooden framework probably took me longer to build than the electronics (big thanks to my mate Graham, who helped with the woodworking side of things).

And does it work?  Well, it’s against the clock, as I said, and the most I have managed to score is 42 (yes, I know: the meaning of life, the universe and everything). Daughter, however, has managed 62… which is really annoying!

Bloody kids!

So, now that’s built, I need another project to keep me busy.

“NEXT!”

Weekend activities

/ masher / 2 Comments

My wrists ache.

I know why: my balls were much too heavy last night.

I should have used lighter ones.

But, that’s the trouble I have with bowling balls: only the really heavy ones have holes big enough for my fat fingers.

One ball – with particularly capacious finger holes – reminded me of an old girlfriend… but, that’s another story.

So yes, we went ten-pin bowling last night – a family outing for Daughter’s birthday.   I won.  Of course.  Me and my big heavy balls.

A good start to the weekend.

And this morning, I have been up to Bletchley Park again, where I had a very pleasant wander round.  I went with a colleague from work and I pretty much acted as an unofficial tour guide for him. He certainly seemed happy enough with my commentary. Hopefully, I got my facts right.

The most enjoyable bit for me, though, was visiting the National Radio Centre and explaining to him – a fairly non-technical person – how radio works. He was fascinated by it all and I think he thoroughly enjoyed the visit. We both did.

Tonight will be spent with pizza and a couple of beers in front of the telly, where we will re-watch Infinity Wars from the Marvel canon, in readiness for Endgame, which will be out soon. But not soon enough. I can’t wait.

And Sunday? Well, I’m not sure whether to start on my next project, or whether I should try sorting the garage out.

Now, I know what I should be doing, but… well, you know.

What the fax?

/ masher / 8 Comments

One of the young millennials at work approached me yesterday and asked “What’s a fax?”

I was somewhat surprised that she didn’t know, but then realised that this was such an old, outdated technology, that it was very likely she would never have seen one before, never mind actually used one.  I explained what it was/is and she went away… probably not much the wiser.

But it got me to thinking about methods of communication.

In the early eighties, I spent a month travelling in California and I wanted to let my parents know that all was well. It was expensive to make international calls back then and sending a letter could take several weeks. So, I sent a Telegram.

Yes: a telegram. Remember them? I think I still have it, somewhere.

But, of course, telegrams were phased out a few years back and can no longer be sent.

STOP

And what about the humble letter? No-one sits down and writes actual letters anymore, do they?   The speed and convenience of email saw to that.

But even email is being pushed out of favour, as the immediate accessibility of today’s Twitters and  Instafaces persuades people to communicate so much more with each other.

But also actually saying so much less.

All Hi and no Fi

/ masher / 7 Comments

Well, it wasn’t the way I planned to spend my Sunday afternoon , but it was enjoyable, nonetheless.

My aging Pure Legato II Hi-Fi started playing up a while ago, giving me its own equivalent of the Blue Screen Of Death: it’s LCD panel, lighting up of its own volition and then refusing to do anything whatsoever.

A factory reset brought it back to its senses, but it didn’t last long and it died again, last week.

I was going to try re-installing the firmware, but Mrs M wanted a quick fix, as she can’t do her ironing without loud music.

Very loud music.

And so, as a temporary measure, I got one of my old amplifiers out of the loft: the venerable Arcam Alpha 5, from the nineties and connected it up to the Sonos system in the living room.

It worked brilliantly… out of one speaker.

The other speaker was quieter than a church mouse with slippers on.

Hmmm… I’m sure it was all working fine when I put it away, all those years ago.

I took the lid off and had a poke around inside. There was nothing obviously wrong, that I could see and so I squirted some switch cleaner onto the switches and pots and gave them a twiddle… wouldn’t do any harm. But still, the left channel refused to make any kind of sound.

And then I noticed the output fuses. I removed and checked them both, only to find that they were intact.

But, when I put them back in, both speakers suddenly sprang into life! I’d fixed it! Yay, me.

I tried wiggling the fuse-holders to see if there was a dodgy joint, but I couldn’t replicate the fault. Maybe it was just some oxidation on the fuse holder blades, I don’t know, but either way it was working, so I put it all back together and fitted it inside the cabinet.

For good measure, I replaced the speakers with something a bit oomphier: a set of Tannoy Revolution R1s.

OK, it took several hours to get it all up and running properly, but Mrs M is happy: she doesn’t care that the sound quality is better than the old one, or that the treble attack is that much faster; she’s just pleased that it’s that bit louder than before.

Telescope or horoscope?

/ masher / 9 Comments

Flicking through the BBC website t’other day, I saw a link which said “Space Calendar: What’s Happening In 2019?”… or something like that.

It turned out to be on the Newsround site – aimed at kids – so it was very easy for me to understand 🙂

I enjoyed the read, until I got to November, where I found an error (which I have highlighted in the picture above).

For some reason I found myself incensed with this and tried to leave a comment on the site, to alert them to their heinous blunder – I mean, how could they confuse celestial mumbo-jumbo with proper science?

Unfortunately, my BBC login wouldn’t allow me to do so, saying that I was way too old to comment on the site – like I was some kind of space-nerd paedo, or something.  This incensed me even further and I started composing a a strongly worded email to the Beeb… before something else caught my attention and distracted me.

And then I lost interest.

Us Taureans have a short attention span, y’see.

Anyway, I’m pleased to see that they have now corrected it.