Potato sprinkle recording

[Harry Dalek]

Today i am working on the recording part hooking up the a head i piniched from from a scrapped tape recorder ,i did make one but this looks pretty .

i have a little amp ..working out the switching of the head and speaker around for record play back ...i am going to plug it into the PC and send it sounds signals and hopefully hear what happens .

[Harry Dalek]

I am thinking of making this play back circuit i am finding the electronic caps numbers a little confusing ...like the first one is that 25volts 6uf..

I have been experimenting since my last circuit did nothing on play back i tested if on a tape recorder head the same so i can see where i went wrong.

Doing tape tests is a good way to test the circuit is working at least ..what i have found is recording is easier than play back .

[Harry Dalek]

Just made this one almost the same as the last but caps were easier to work out .

So hope this will fix the play back ,i will test it on an old cassette deck wiring the head to the circuit .

Same gos for the other side ....record using this circuit by a very clever young fellow on you tube
http://www.youtube.com/watch?v=kABtfVEJAH0
It sort of rolls the bias, that improves the fidelity of analogue magnetic tape sound recordings into one little 555 timer circuit .

[Klaas Robers]

I guess the indication of the capacitors is the other way around. So 200V6 is 200 uF at 6V. But I never have seen this way of indicating the capacity and the max voltage. The input capacitor by the way is 2.5 uF.

There is absoluterly no reason to use a 200V capacitor in a circuit that is powered from a supply of 12V.

[Harry Dalek]

I guess the indication of the capacitors is the other way around. So 200V6 is 200 uF at 6V. But I never have seen this way of indicating the capacity and the max voltage. The input capacitor by the way is 2.5 uF.

There is absoluterly no reason to use a 200V capacitor in a circuit that is powered from a supply of 12V.

Thanks for that Klaas

It had me wondering i had not seen this either.

I ended up making the second version ...both the record and play back circuits are made but haven't had time to test yet for once i have had lack of time .

[Metallica Man X]

Looks cool! I wonder how good of quality the wound will be....the next step with this little guy would be to use it to record NBTV signals (provided the quality is high enough lol)

[Harry Dalek]

Looks cool! I wonder how good of quality the wound will be....the next step with this little guy would be to use it to record NBTV signals (provided the quality is high enough lol)

I am at the testing circuit trouble shooting stage MMX...it will record for a few seconds with the speed its doing and the thread that drives the head arm.
It had crossed my mind to try NBTV onit but i will do little steps i will be happy with any type of recording ...the recording part is easy the play back is some thing i have not tried correctly yet..record you can test on a scrapped tape deck and play back to test but play back on this so i can only test on this as there is but one !
I checked my circuits today the record one looks to work fine ....The play back circuit in my post or 2 ago the 3.3k across the + power rail between the 741 and transistors needs changing its value to a touch higher might stick a pot in or just test what works best with my resistor wheel ...i am using BC 548 transistors and kept all the part values in that circuit ..and am testing with 12 volts .
So looks like its worth a hook up to the head to see.

[Viewmaster]

It had crossed my mind to try NBTV onit but i will do little steps i will be happy with any type of recording .

The NBTV sync pulses are quite high frequency (.1 to .25 msec) so unless your recorder can handle this, forget them.

On my experimental wax cylinder recorder (The Edikow machine), I suppress the sync for recording (which gives better signal/noise as a bonus) and reinstate the sync by mechanical means on playback. If you ever try to record NBTV, it is easier to record an exact number of frames per rev and the sync can then be reinstated.

[Harry Dalek]

It had crossed my mind to try NBTV onit but i will do little steps i will be happy with any type of recording .

The NBTV sync pulses are quite high frequency (.1 to .25 msec) so unless your recorder can handle this, forget them.

On my experimental wax cylinder recorder (The Edikow machine), I suppress the sync for recording (which gives better signal/noise as a bonus) and reinstate the sync by mechanical means on playback. If you ever try to record NBTV, it is easier to record an exact number of frames per rev and the sync can then be reinstated.

Hi Albert

I just finished experimenting theres a big problem mistake in the design using the tin the seam causes a big jump noise i was not expecting every time it gos around and the tin does not record well with this i can just hear stuff ...the head has to touch the Can this makes it worse .

So stuff that i will redesign part again .

It would be nice to try NBTV if i can get it good enough ...least trying what i have i know what to do to get close now learning from mistakes sure works .

I think your cylinder recorder is a great machine...i have to look at yours again i suppose you used an encoder slot disk on it to match what you said amount of frames as the thing revolves once.

Working on magnetic recording have learned what works and what doesn't ...the play back head can be connected to a preamp for a magnetic mic input so any old circuit that does this will work with a cassette recorder head .

This head does both ...record play back the the plastic one in these things is erase head ...whoops that was a mistake.

On record you could just connect a amp that drives a speaker right to the head instead .
But its better to use an oscillator running around 40khz i suppose similar to a pwm system for nbtv luxeon or laser modulation .

Started knowing bugger all apart from these things used an electromagnet .

[Viewmaster]

I just finished experimenting theres a big problem mistake in the design using the tin the seam causes a big jump noise i was not expecting every time it gos around and the tin does not record well with this i can just hear stuff ...the head has to touch the Can this makes it worse .

I don't know how accurate it revolves but if you get the head withing a few thou it might pick up OK. If it revolves not true maybe something called'an advance ball' might help. I use this on my machine. A small ball connected to a floating head runs on the surface just ahead of the detecting head (or cutter on mine) This will raise or lower the head and so keep it the exact distance from the recording surface.

i suppose you used an encoder slot disk on it to match what you said amount of frames as the thing revolves once..

Yes, as I have 'exactly' 3 frames per rev, so a swinging opto fork can generate new sync pulses from encoder holed disk. Another system blanks out the 31/63/95 pulse for framing via an AND gate......still experimenting BTW !

Working on magnetic recording have learned what works and what doesn't .

That's the way to do it, Harry......carry on working.

[Harry Dalek]

Hi Albert

I don't know how accurate it revolves but if you get the head withing a few thou it might pick up OK. If it revolves not true maybe something called'an advance ball' might help. I use this on my machine. A small ball connected to a floating head runs on the surface just ahead of the detecting head (or cutter on mine) This will raise or lower the head and so keep it the exact distance from the recording surface.

Theres is a slight up down movement once again due to handy man construction ,i was expecting a fade in fade out problem your idea of wheel keeping the correct distance is a very nice idea i will have to look into this ...i suppose the tape and roller in a cassette does this in reverse ..which is easier adjust a tape to a head an a head to a tape .

Yes, as I have 'exactly' 3 frames per rev, so a swinging opto fork can generate new sync pulses from encoder holed disk. Another system blanks out the 31/63/95 pulse for framing via an AND gate......still experimenting BTW !

Oh yes some things take ages ! i like your never give up attitude,if i ever try the nbtv signal your pioneering work information might come in handy .

That's the way to do it, Harry......carry on working.

[/quote]

Yes i have taken the tin off for now wrapped in video tape ..i wanted to stay clear of tape for a while but it works with tape just trying it with strip of it ,so i will see how this gos not sure if the wrapping will have the same effect as the seam on my tin but will give it a shot .

[Harry Dalek]

Heres the redesign the old Potato sprinkle now wrapped in video tape ,i have redesigned the head arm so it can be positioned ,Albert has inspired me .
From playing around with it the head position is pretty critical ,the head should really be curved in to match the drum so thats the wrong way around for this .
So i will give this a go and hear what happens..i hope the over lapping tape works .

[Viewmaster]

From playing around with it the head position is pretty critical ,the head should really be curved in to match the drum so thats the wrong way around for this .
.

To simulate a reel to reel tape recorder I could give you piles of work, Harry, by suggesting that the tape is put 'inside' the drum.
The head mounted on an arm, ( just like internal boring on a lathe. )
Now the head would be in good contact with the recording tape, a convex head mating with concave tape.

OR, and this is much less work......as your present design, but the tape wound over thin foam sheet on the drum. The head slightly sprung into the tape and so indenting into the foam. This would achieve the convex head to concave tape mating............................maybe
You would need more power to drive this due to increased friction.

BTW, I read that as Friedrich Matthias invented the tape medium, including oxide and backing material, you could call your machine, if ever adapted to NBTV,
"The Matkow machine," (MATthias/nipKOW)

[Harry Dalek]

Hi Albert

To simulate a reel to reel tape recorder I could give you piles of work, Harry, by suggesting that the tape is put 'inside' the drum.

I needs to be in contact with the tape i am finding but i would rather that no wear !
I suppose it would depend on how much power you are feeding the head ,or how well you preamp can pick up the recording ? A Hall effect sensor might make a very good solid state pick up head it would be good if it worked pity you can't record with the thing.

The head mounted on an arm, ( just like internal boring on a lathe. )
Now the head would be in good contact with the recording tape, a convex head mating with concave tape.

This i am finding to be a problem...recording seems good on a scrapped test cassette insides more than likely due to this system the contact tape wrapped to shape so i think theres not enough of the head contacting the tape similar results to the tin can apart from no seam being picked up.

OR, and this is much less work......as your present design, but the tape wound over thin foam sheet on the drum. The head slightly sprung into the tape and so indenting into the foam. This would achieve the convex head to concave tape mating............................maybe
You would need more power to drive this due to increased friction.

Thats a very good idea Albert i don't think that would of come to mind ! Yes to much friction might be a problem the stepper motor running off 6v AC stops and runs the other direction if theres to much force.

BTW, I read that as Friedrich Matthias invented the tape medium, including oxide and backing material, you could call your machine, if ever adapted to NBTV,
"The Matkow machine," (MATthias/nipKOW)

I like that name Albert ..still some work to do i was thinking the electronics would be the problem when i started this and its turning out more head to magnetic material .