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Karen O 8th Sep 2019 5:39 pm

Digital 'cassette' recorder
 
1 Attachment(s)
I can't recall if I have already posted about this project. If I have, feel free to delete this post!

I confess to disliking computer apps immensely. I find them unintuitive, fragile, and infuriating. So, rather than settle for a computer-based audio record and playback system, I've built my own that has the ease and simplicity of an old school cassette recorder! The cassette is a compact flash card. The controls are a familiar row of locking buttons. The progress indicator is a numeric LED counter. None of your file system rubbish here - it just records linearly onto the sectors ;D

I've made numerous compact flash readers before in order to generate obsolete television standards. This is the first time that I have attempted recording. The reason: the PICs driving these things have next to no buffering. The PIC simply cannot hang around while sectors are erased and written. A solution was found be pre-erasing the sectors prior to write. If you do this, then there is no write latency to speak of.

So far I've recorded a couple of albums onto the 'cassette' (capacity is about 170 minutes).

Cool eh? :)

mole42uk 8th Sep 2019 6:10 pm

Re: Digital 'cassette' recorder
 
I am impressed! Please can we see details? That's the sort of 'analogue' device that I'd love to have.... Maybe I'd use SD cards as I seem to have so many.

OscarFoxtrot 8th Sep 2019 6:19 pm

Re: Digital 'cassette' recorder
 
There's a serious market for that sort of thing in the care sector especially for people with dementia.

ValvoStef 8th Sep 2019 7:11 pm

Re: Digital 'cassette' recorder
 
Quote:

Originally Posted by mole42uk (Post 1174671)
I am impressed! Please can we see details? That's the sort of 'analogue' device that I'd love to have.... Maybe I'd use SD cards as I seem to have so many.

Yep, I would like to see the details as well. A really useful peace of kit., Karen.

Martin Bush 8th Sep 2019 7:13 pm

Re: Digital 'cassette' recorder
 
One of the best ideas I've seen this year :)

suebutcher 9th Sep 2019 3:08 am

Re: Digital 'cassette' recorder
 
Kudos, Karen! This is what a machine should be, a device that does one task well and is easy to operate.

suebutcher 9th Sep 2019 3:11 am

Re: Digital 'cassette' recorder
 
Quote:

Originally Posted by OscarFoxtrot (Post 1174674)
There's a serious market for that sort of thing in the care sector especially for people with dementia.

Otherwise we'll need an huge army of "tech-carers" to operate overly complicated domestic appliances for old folk. I mean, even the simplistic "granny phone" is a thing of the past in this country. If you need a mobile that isn't loaded with unnecessary features, you've got to buy it second-hand now.

Dai Corner 9th Sep 2019 7:44 am

Re: Digital 'cassette' recorder
 
I like that idea Karen, and your implementation. My stepfather (86) cannot get to grips with modern appliances and would love something similar.

Sue - I don't know about Australia but you can still buy basic mobile phones new in the UK. They're usually marketed as rugged devices for use in harsh environments. The following link is an example not a recommendation.

https://cpc.farnell.com/c/computer-o.../mobile-phones

Terry_VK5TM 9th Sep 2019 12:19 pm

Re: Digital 'cassette' recorder
 
Nice project Karen and as others have said, ideal for the "older generation".

Now if you could just make the flash card look like a cassette...;D

You can still get the "granny" mobile phones here in Oz, you just wont find them on display (they want to sell you the all singing, all dancing modern fandangled stuff), you have to ask and they will slink off and pull one from a remote draw at the back of the store.

We've got one in the Mens Shed with large buttons, alarm and torch function.

Tazman1966 9th Sep 2019 3:43 pm

Re: Digital 'cassette' recorder
 
What a cracking idea! Surely there must be a market for this?

Karen O 9th Sep 2019 10:02 pm

Re: Digital 'cassette' recorder
 
The idea behind my 'cassette' recorder is simple and can be extended to a traditional radio. Imagine a traditional scale with a pointer moved by a 'tuning' knob. The knob controls a potentiometer which inputs a voltage to a microcontroller. This then uses the voltage to select one from, maybe, a dozen pre-selected internet radio stations (e.g. Dismuke, etc.)

No LCDs, no menus, no lists to have to peer at. Just a knob and a scale. In the days that I listened to the radio I didn't use the frequency, wavelength, or even the name of the station it identify a station. I knew R2 was at about one third of the scale, that easy listening station at just over half scale. I might place coloured stickers on the glass. I could even countenance a removal scale that can be pre-printed or marked up manually. But never would I want to scroll down a list of station names.

About my implementation: It is not the right way to do it! Mine is an exercise in extreme PIC programming. That poor PIC doesn't have a moment to spare - every routine is carefully cycle counted. It is obscure, impenetrable and completely unmaintainable. To call it a can of worms would be to insult worms.

My disdain is for modern user interfaces and not the technology per se. If I were doing it properly I would hide a RPi in that box. It has the general purpose I/O to drive the LEDs and the buttons. And its OS can read and write SD cards, USB thumb drives or even a network file system with just a change in a file name.

So, are there any RPi programmer up for this challenge?

SiriusHardware 9th Sep 2019 11:10 pm

Re: Digital 'cassette' recorder
 
You can find Raspberry Pi Internet radio projects already detailed throughout the internet, for example, this one has all the necessary code ready made and ready to go:

https://bobrathbone.com/raspberrypi/...net_radio.html

Most are described at a more fundamental level with the minimal amount of Python code needed to get started, like this one.

http://www.suppertime.co.uk/blogmywiki/piradio/

I have in my possession a redundant OAP's dispersed alarm unit which has four big chunky Fisher-Price like buttons on the top panel, along with a 2 * 16 character LCD display, curiously styled rather like an Art-Deco mantlepiece radio - it would be perfect for conversion to an internet radio.

Anyway, back to the original 'Tape Recorder' project, that's a brilliant project. The 'tape counter' is essential since you can't actually see the sizes of the 'reels' to judge where on the tape you are. This would be perfect for use with 70s/80s home computers.

suebutcher 10th Sep 2019 2:59 am

Re: Digital 'cassette' recorder
 
And for modern computers too! People are so hung up on this "select from menu, download a file, choose an app" business, aren't they? I was talking to an old chap (well, just slightly older than me!) at the Repair Café, and he told me he had some music in his computer he wanted to download as a keeper for listening. He didn't know how to do it. "Join the club!" I thought. I said, "You don't have to download a file, just plug a good recorder in to the headphone socket, get the computer to play the music, and there you are." But he didn't even acknowledge that suggestion. "I want to get this music and I don't know how to download!" Oh dear.

mole42uk 10th Sep 2019 6:50 am

Re: Digital 'cassette' recorder
 
Quote:

Originally Posted by Karen O (Post 1175004)
Mine is an exercise in extreme PIC programming. That poor PIC doesn't have a moment to spare - every routine is carefully cycle counted.

That's the way we used to program Z80s - when the poor 4MHz chip was made to work for its living. Counting clock cycles per instruction? Of course, that way you could get it to work harder & faster, and when you have only 8k of ROM, making every instruction relevant really matters.

RPi Zero is probably the way to go with your cassette recorder but I never found out how to program those in machine code, and I never really learnt any sort of higher level language....

Radio Wrangler 10th Sep 2019 8:39 am

Re: Digital 'cassette' recorder
 
Menu interfaces have got into the most inappropriate places. The latest cars seem to have gone all-touchscreen. Drivers have to look down at a centre console to see where their finger is pointing and what mode the screen is in when all they want to do is adjust the heater. It doesn't matter whether the driver is of the computer generation or not, they'll live longer if they kept their gaze out of the window.

Karen's cassette player is gorgeous. It's not an interface that's efficient for getting to any chosen track, but it is an interface designed to be familiar and comfortable to a lot of people.

Interfaces should always be designed around the human, not around the machine.

Inappropriate interfaces can cost lives.

David

mole42uk 10th Sep 2019 8:50 am

Re: Digital 'cassette' recorder
 
Quote:

Originally Posted by Radio Wrangler (Post 1175057)
Karen's cassette player is gorgeous. It's not an interface that's efficient for getting to any chosen track,

Some of us will remember that, when playing an album on tape or disc, one would listen to the movements or the tracks in the order that the composer or producer had decided was optimal. ISTR turning a disc over to play the other side immediately the first was finished!

Radio Wrangler 10th Sep 2019 9:52 am

Re: Digital 'cassette' recorder
 
I find that things like iPlayer like to order tracks alpha-numerically and therefore without manual intervention will feed me the movements of, say, Shostakovitch's 7th symphony in the wrong order. So you get the events of the second world war shuffled!

David

Dai Corner 10th Sep 2019 10:00 am

Re: Digital 'cassette' recorder
 
Quote:

Originally Posted by suebutcher (Post 1175040)
And for modern computers too! People are so hung up on this "select from menu, download a file, choose an app" business, aren't they? I was talking to an old chap (well, just slightly older than me!) at the Repair Café, and he told me he had some music in his computer he wanted to download as a keeper for listening. He didn't know how to do it. "Join the club!" I thought. I said, "You don't have to download a file, just plug a good recorder in to the headphone socket, get the computer to play the music, and there you are." But he didn't even acknowledge that suggestion. "I want to get this music and I don't know how to download!" Oh dear.

The simplest way is often the best. People forget that our ears are analogue devices which can only receive sound waves. Any digital source, even with DRM protection, can be recorded by tapping into the chain at the appropriate point. A microphone in front of the speaker if necessary.

SiriusHardware 10th Sep 2019 10:08 am

Re: Digital 'cassette' recorder
 
As the data is 'recorded' in analogue-like linear fashion on the card, it should be possible to add a Sharp-like facility to search backwards or forwards to the next 'silence' between 'tracks' - what did Sharp call that feature again - 'AMSS', or something similar...

Dai Corner 10th Sep 2019 10:27 am

Re: Digital 'cassette' recorder
 
Quote:

Originally Posted by SiriusHardware (Post 1175081)
As the data is 'recorded' in analogue-like linear fashion on the card, it should be possible to add a Sharp-like facility to search backwards or forwards to the next 'silence' between 'tracks' - what did Sharp call that feature again - 'AMSS', or something similar...

Auto Programme Search System (APSS) I think.


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