"I used to eat a lot of Tracker bars at one time. Is that the origin of the name of the blog?"
I have to admit that I have not tried.... or even seen a 'Tracker' bar. Well perhaps I have seen one but not noticed it.
This blog takes it's name from the tracker-bar in the organ.
The Tracker-bar is equivalent to the playback head on a cassette player, but instead of the magnetic signals the organ gets its pneumatic signals (puffs of air) from the holes in the paper roll as it passes over.
In some organs the air that goes down the hole in the tracker-bar actually blows the corresponding pipe but in this case it is necessary to cut slots in the card/paper rather than a row of holes. The problem with this system is that the pipes, being of different sizes, require different amounts of air. If all the slots were the same width, the bass pipes would not get sufficient air, whilst the top pipes may ‘over-blow‘. The holes in the tracker-bar for the bass pipes are therefore made larger. (4mm)
In organs where the paper rolls have lines of separate holes representing the note duration, the air through the tracker-bar operates valves which in turn allow air to the pipes.
This has the advantage that all the holes can be the same size and instead of requiring slots, a row of closely spaced holes is enough to keep the valve open.
The Tracker-bar holes on my organ are only 2.8mm diameter but this is enough to inflate the “puff” to operate the larger valve.
I don't expect many to count the holes on the bar, but on this 26note organ there are actually 27 holes. The 110mm wide paper is wide enough to punch an extra hole. The music still has 26 notes and the extra hole can be used to operate a conductor, a bell ringer or drum.
There is another 27 hole organ over in Australia....I'll have to request a larger print from Derek so that you can see the excellent five carved Bandsmen.
2 comments:
Aaaah, right.
I don't know if you can buy Tracker bars any more. They would be next to the cereal bars if you want to have a look. Choc chip was my favourite.
The musical box harps are lovely. What a great original present for a child to have.
I wonder - why "Kippers Dickie"? Did you once have a cat called Kippers and a cat called Dickie?
Re-printed from my first post in January.
Quite a few people have asked me why "Kipper's Dickie".
Well, twenty years ago, as an engineer, I worked for Plessey. The site where I worked had a post-room staffed by two lovely ladies who's job it was to collect and deliver all the mail.
In addition to this they were a never ending source of news, scandal, gossip, rumour, tittle-tattle etc....They were the first to know about most of the "going's on" on and around the site. I am not suggesting that they "steamed" open letters, but this was the first place to go to get the latest on "so and so" or about "such and such".
"One of these days, you'll get into trouble for spreading rumours like that" I said.
"I don't care" she said.
"I don't care a Kipper's Dickie".
So now you know.....
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