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- Path: sparky!uunet!europa.asd.contel.com!emory!swrinde!news.dell.com!natinst.com!cs.utexas.edu!torn!nott!cunews!freenet.carleton.ca!Freenet.carleton.ca!aa339
- From: aa339@Freenet.carleton.ca (Etienne Tasse)
- Subject: Re: Windows 3.1 Covox/LPT DAC Driver (1/1)
- Message-ID: <1992Dec18.025508.17408@freenet.carleton.ca>
- Sender: news@freenet.carleton.ca (News Administrator)
- Reply-To: aa339@Freenet.carleton.ca (Etienne Tasse)
- Organization: The National Capital Freenet
- References: <JASKA.92Dec17173154@stekt5.oulu.fi> <1fjaaqINNg1@usenet.INS.CWRU.Edu>
- Date: Fri, 18 Dec 1992 02:55:08 GMT
- Lines: 58
-
-
- In a previous article, jaska@stekt5.oulu.fi (Jaakko Heikkil{) says:
-
- >In article <1fjaaqINNg1@usenet.INS.CWRU.Edu> cj337@cleveland.Freenet.Edu (Etienne Tasse) writes:
- >> Here is a Sound WAV driver for Windows 3.1 for:
- >> - Covox Speech Thing
- >> - Digital to Analog Homebrew (DAC08/ZN428/R2R) connected to Printer Port
- >
- >> Enjoy!
- >
- >Great! But I havent't yet found instructions for building Covox. Where
- >I can found it? How about DAC? Any information available? Please tell
- >me for examble an issue of some magazine where I can read more about
- >those sound"cards".
-
-
- The "R-2R" schematic can be found with Mark J Cox's MODPLAY PRO (MP219B.ZIP)
- Here it is in ASCII format.
-
- 3. HOW TO MAKE AN EVEN CHEAPER D/A
- ----------------------------------
-
- For the price of 20 1% resistors and a plug, with no power supply
- needed you can make a D/A converter that sounds close to the IC
- one above (it seems only the UK can get a Plessey ZN426E)
-
- You need one plug for your amp, one for your parallel port and
- 9 20k and 9 10K resistors
- Use 1% resistors if possible ─ and 20k sound much better than 22k
-
-
- 20 2 3 4 5 6 7 8 9 <- DB25 Pin #
- GND D0 D1 D2 D3 D4 D5 D6 D7 <- Signal Name
- | | | | | | | | |
- | R2 R2 R2 R2 R2 R2 R2 R2
- | | | | | | | | |
- | |_R1__|_R1__|_R1__|_R1__|_R1__|_R1__|_R1__|_R1____C1_ +
- | | |
- | R2 R1 TO AMP
- |_____|______________________________________________|_____ -
-
- R1 = 10K 1%
- R2 = 20K 1%
- C1 = 100nF
-
- Thanks to Harry Stox for the above circuit. Again, make sure all
- the 0v lines are connected together. The 100nF capacitor may not
- be needed, try removing it if this circuit sounds poor.
-
- HARDWARE.DOC (c) Mark J Cox
- --
- Etienne TassEh? // Internet> aa339@freenet.carleton.ca // Earth:
- Ottawa, Canada // Fidonet> U=Floyd A=1:163/524 // Mostly Harmless.
-