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Re: Mutron Phaser II

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9/7/1999 6:03 PM

Re: Mutron Phaser II

One thing to remember about the Phaser II is that it has a custom LED/LDR device that has 3, yes count'em, 3 CT photocells all controlled by one LED in a 10 pin can. I have thought about trying to make some but the housing has been my biggest obsticle. First thing to look at when repairing a Phaser II is to confirm the oscillator is driving the LED. You should see an LF sine wave at one pin of the can LED/LDR.

CJ landry

9/7/1999 6:48 PM
Dave James	AH! This is the kind of info I need. I've seen that 10 pin can and wondered what it was...now I know. Later, DJ

9/7/1999 7:10 PM
R.G.	That's an important clue. If a phaser uses LED/LDR's, it's almost certain to be the standard "string of opamps" phaser with an LDR for the variable resistor in each phase change stage (refer to the Technology of Phasers and Flangers at GEO). Given that, you can almost just draw the schematic, except for the LFO, and even that is probably a triangle LFO.

9/7/1999 8:20 PM

I could probably draw it up, or par...

I could probably draw it up, or parts of it anyway, if I can ever find the time. I know it'll be at least a couple weeks till I can work on it (sorry). The ICs on mine say:

P624 then looks like a Texas Intruments logo, at least something vaguely in the shape of Texas then 0821.

Does anybody know what it is...if that's roughly the same IC used in the Small Stone? There are 6 of these IC and no other ICs on the board. Also 3 transistors.

JD

9/7/1999 8:22 PM
JD Sleep	Mutron Phaser 2 Sorry I meant for this to go into the Mutron Phaser II thread.

9/7/1999 10:46 PM
Dave James	Re: JD, I'll pop mine open tonight and see what's listed on the ICs. Later, DJ

9/8/1999 3:08 PM
Dave James	JD, I opened the Mutron last night during ST:TNG. Here's what I found: 1) all ICs (6 ea.) are RC4558NB with a date code of 7910 2) there are 3 xistors; 2 - 2N3904 and one located by the power switch - 2N3906. 3) the 10 pin custom pack is labeled with HTV P635 9FM. Later, DJ

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