Electronics World articles Popular Electronics articles QST articles Radio & TV News articles Radio-Craft articles Radio-Electronics articles Short Wave Craft articles Wireless World articles Google Search of RF Cafe website Sitemap Electronics Equations Mathematics Equations Equations physics Manufacturers & distributors Engineer Jobs LinkedIn Crosswords Engineering Humor Kirt's Cogitations RF Engineering Quizzes Notable Quotes Calculators Education Engineering Magazine Articles Engineering software RF Cafe Archives RF Cascade Workbook 2018 RF Symbols for Visio - Word Advertising RF Cafe Forums Magazine Sponsor RF Cafe RF Electronics Symbols for Visio RF Electronics Symbols for Office Word RF Electronics Stencils for Visio Sponsor Links Saturday Evening Post NEETS EW Radar Handbook Microwave Museum About RF Cafe Aegis Power Systems Anritsu Alliance Test Equipment Amplifier Solutions Anatech Electronics Axiom Test Equipment Berkeley Nucleonics Bittele Centric RF Conduct RF Copper Mountain Technologies Empower RF everything RF Exodus Advanced Communications Innovative Power Products ISOTEC KR Filters Lotus Systems PCB Directory Rigol RF Superstore San Francisco Circuits Reactel RFCT TotalTemp Technologies Triad RF Systems Windfreak Technologies Withwave LadyBug Technologies Wireless Telecom Group Sponsorship Rates RF Cafe Software Resources Vintage Magazines Thank you for visiting RF Cafe!

16bit / 48KHz PCM Audio Recorder? - RF Cafe Forums

RF Cafe Forums closed its virtual doors in 2010 mainly due to other social media platforms dominating public commenting venues. RF Cafe Forums began sometime around August of 2003 and was quite well-attended for many years. By 2010, Facebook and Twitter were overwhelmingly dominating online personal interaction, and RF Cafe Forums activity dropped off precipitously. Regardless, there are still lots of great posts in the archive that ware worth looking at. Below are the old forum threads, including responses to the original posts.

NOTICE: The original RF Cafe Forum is available again for reading, and the new RF Cafe Blog is an active board.

-- Amateur Radio

-- Anecdotes, Gripes, & Humor

-- Antennas

-- CAE, CAD, & Software

-- Circuits & Components

-- Employment & Interviews

-- Miscellany

-- Swap Shop

-- Systems

-- Test & Measurement

-- Webmaster

HazyWinter

Post subject: 16bit / 48KHz PCM Audio Recorder? Posted: Sat Jan 27, 2007 2:23 am

Captain

Joined: Sun Jan 21, 2007 4:57 am

Posts: 6

I'm trying to build a PCM (wav) audio recorder that would have some basic controls like record (duh), play, pause, next track, previous track and have the ability to start a new file for each recording. I'm looking for the absolute lowest noise floor possible, that's why I'm not hacking an mp3 recorder or some such consumer device.

The main goal here is to have the smallest recorder possible because of limited space inside the housing of a wideband radio receiver.

If anyone can give me some pointers on where to start, schematics, parts, a rough block diagram, it'd be nice.

Top

fred47

Post subject: PCM recorderPosted: Tue Jan 30, 2007 1:37 pm

General

Joined: Wed Feb 22, 2006 3:51 pm

Posts: 104

Hi!

OK, physical size is important. How do:

1. Cost (per unit)

2. Cost (to develop)

3. Power consumption

4. Volume

5. Total recording time

rank in importance to you?

Do you need stereo/5.1/7.1/other multi-channel recording?

Do you need analog playback, or does the signal get out of the recorder in digital form (for example, SPDIF)?

What about monitoring what's recorded?

Are there any available resources in the receiver that you don't have to implement for your recorder? (I assume power supply, but there might also be program storage space, so that a flash EPROM wouldn't be necessary - a program could be downloaded onto a single-chip microprocessor or DSP).

Good luck!

Fred

Top

HazyWinter

Post subject: Posted: Tue Jan 30, 2007 4:10 pm

Captain

Joined: Sun Jan 21, 2007 4:57 am

Posts: 6

Hi Fred,

Power is supplied by three AA 3000mAh batteries for a total of 3.5v - 4v.

Volume is not really a factor since the output from the receiver will be soldered directly to the recorder's input. In other words, this is going to be a straight line level (about 200mV) audio connection. As far as channels are concerned it doesn't have to go beyond stereo, so 2 channels should be enough.

Analog playback will not be nessecary. In fact, a mini USB connection would be ideal for file transfers to a PC.

The receiver uses a Mitsubishi M38267M8L-256GP CPU and an Asahi Kasei Microsystems (AKM) Serial CMOS EEPROM model AK93C10A along with a Rohm DTA144EE Digital Transistor.

Some other components of note are: TI Differential Opamp & M35017-001FP On Screen Display.

Top

fred47

Post subject: RecorderPosted: Tue Jan 30, 2007 9:17 pm

General

Joined: Wed Feb 22, 2006 3:51 pm

Posts: 104

Oops, my fault in not asking the questions clearly.

When I said "volume" I meant like "cubic inches", not dB!

How long does it need to record for? If it's seconds, some chips have enough memory on-board. Minutes implies external RAM, hours implies Flash - so it's important to know the size of the records.

sounds like power efficiency is critical, too - at 11 Watt-hours battery, you couldn't use a 1W DSP, for example.

Good Luck,

Fred

Top

HazyWinter

Post subject: Posted: Tue Jan 30, 2007 9:59 pm

Captain

Joined: Sun Jan 21, 2007 4:57 am

Posts: 6

I'm aiming for 4 hours of storage, so a flash based storage system is a must, either NAND, SD, or CF. If space becomes an obstacle then I can make the housing a little taller and wider to accommodate all the components. It's a cast magnesium alloy and I have a place that can do that from a 3D CAD file.

Volume wise, I can only think of a rough figure right now, something in the neighborhood of 6 cubic inches; 3L x 2 W x 1H.

Posted  11/12/2012

RF Cascade Workbook 2018 - RF Cafe
Amplifier Solutions Corporation (ASC) - RF Cafe
Innovative Power Products Passive RF Products - RF Cafe
Innovative Power Products Passive RF Products - RF Cafe
TotalTemp Technologies (Thermal Platforms) - RF Cafe

Please Support RF Cafe by purchasing my  ridiculously low−priced products, all of which I created.

These Are Available for Free

 

About RF Cafe

Kirt Blattenberger - RF Cafe Webmaster

Copyright: 1996 - 2024

Webmaster:

    Kirt Blattenberger,

    BSEE - KB3UON

RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while tying up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

My Hobby Website:

AirplanesAndRockets.com