Simple and Cheap Audio Recorder/Player kit

[BigRez]

I was browsing through Fry's the other day and noticed they had  a 40 Second Message Recorder kit for sale at $9.90 each.  The kit comes complete with all parts - you just solder them on to the board.  Made by Twin Industries, and on their site selling for $29.99, thought I'd give it a try. (I bought all three at the Manhattan Beach store.) Took me about an hour to assemble it - hardest part was figuring out which resistors were which.  :D

After poking around, I found that the board is similar (but not identical) to the Cowlacious board.  It uses and comes with the ISD1740 ChipCorder but can use all of the ISD1700 chips for longer messages (up to 480 seconds). You can record using a built-in or external mic, and play back up to 40 seconds at the default rate.  I recorded several five-second sounds and was able to cycle through them.  

I'm gonna try connecting it to the prop-1 (should be easy) using the push-button connections, but there's also an SPI Interface which is supposed to allow much greater operation.  I'll have to check that out soon.

Anyway, for $10 and just a little work, I think it's a good device for simple sounds.  

[JackMan]

Can't beat it for $10 but just to clarify it uses the ISD25xx series chips, not the 17xxx series.  Here's a pic from the website.

[JonnyMac]

That is a deal since the ISD25xx series is long out of production.  We actually inquired with a components brokerage service to extend the life of the AP-8; they came back with a $35 price for the ISD2560 and thought they were getting us a good deal!  Uh... no.

The ISD17xx series can record at 12kHz, but only if you make a power-supply adjustment that they don't document; if you don't, playback can be faulty.  How do I know? -- through a lot of frustrating hours of product development that ultimately lead to me unleashing the "Evil JonnyMac" on the Winbond (now Nuvoton) engineering department more than once.  Their excuse was that the guy who wrote the 17xx docs -- long since terminated -- never actually used the chip! 

[BigRez]

Their older version (which is listed on the Fry's website but not available in the store) uses the  ISD25xx chips but the new version, the ones I bought, all have the ISD1740 chip. That's the one I see at  http://www.twinind.com/catalog_detail.php?id=243 and also verified on my devices and their documentation.

The instructions also document how to change the sampling frequency (using different resistors), from the default is 8kHz to higher and lower.  I soldered the resistor into the first one but will make a socket on the next board so that I can switch it.

[JonnyMac]

The problem is the power supply.  For absolute reliable operation of 12kHz sampling the power supply has to be reduced from 5v to 4.3v -- I got this in the form of an internal memo from Nuvoton after proving to them that the 17xx series didn't work per spec (sometimes 12kHz playback is garbled when the power supply is 5v).  Needless to say, I know far more about the 17xx than I ever expected I would....

[JackMan]

That's interesting. I bought several Cowlacious boards a few months back and they all have the garbled problem when there's multiple messages on the chip and a single message is erased. At that point, any new recordings are garbled until the entire chip is erased and all new recordings are performed. This is at 12kHz and of course the on-board 5v regulator. I emailed back and forth with Carl several times (great guy to deal with by the way) but he didn't know what could be causing the problem. My apologies to bigrez on the chip description of the Fry kit.  ;)

[Jeff Haas]

I've been to a couple of local Fry's and they're all out of the kit. The only one in stock is in Sacramento, CA... a mere 100 miles away.
:-\

[BigRez]

I ordered two more from their on-line site and they came as identified above, with the ISD1740 chip, and still at the $9.90 price.

[Jeff Haas]

I tried that too, but the website is out of stock as well.

[JackMan]

Yeah, I tried that as well, SOL. The website says delivery is unavailable and then directs you to your nearest store but there are none available there either. It won't allow an order to be placed for store delivery/pickup.  :(

[BigRez]

Well I guess Frys really messed up because I got four of these at the $9.90 price.  Everywhere else I've seen on-line they're going for $30 and up.

I just picked up a couple of ISD17240PY-ND chips from Digikey.com ($12/ea), plugged one in, and recorded multiple segments totalling about 200 seconds.

[JonnyMac]

Be careful with the ISD1700 series: there is a problem on the die that can cause garbled playback when 12kHz is used and a single segment is erased.  Ask me how I know... (hint: I'm not terribly popular with the engineering staff at Winbond and they finally sent me internal documents regarding the problem).

[JackMan]

Yeah, the Cowlacious boards have that problem, at least all of mine do. Per my emails with Carl, he is not aware of it.  :-\