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Stereo MPX Decoder for old Sony
#12

I didn't need to adjust any levels. It is happy just the way it came. The only thing is there is no deemphasis on the output. The sony has it already from the original circuit. 

Your LM4500 IC looks to be the easiest to work with as it's a old school dip package. There are still some on ebay. As far as function it looks a lot like the AN7416. 

Now I am waiting for new driver transistor for the output. The bias keeps drifting up. It already blew out the finals on one channel. I found one of the drivers had a gain of 86 and the bad channel one had gain of 2 and kept getting really hot.

!!!!!!!!!!!!!!!!!!!RESISTANCE IS FUTILE!!!!!!!!!!!!!!!!!!!!!!  
                           /\/\/\/\/\/\/\/\/\
                                                     
                                 [Image: http://philcoradio.com/phorum/images/smi...on_eek.gif]  Chris


Messages In This Thread
Stereo MPX Decoder for old Sony - by OZ4 - 08-31-2021, 12:03 AM
RE: Stereo MPX Decoder for old Sony - by OZ4 - 09-02-2021, 11:04 PM
RE: Stereo MPX Decoder for old Sony - by OZ4 - 09-03-2021, 12:03 AM
RE: Stereo MPX Decoder for old Sony - by OZ4 - 09-13-2021, 05:30 PM
RE: Stereo MPX Decoder for old Sony - by OZ4 - 09-13-2021, 09:38 PM
RE: Stereo MPX Decoder for old Sony - by OZ4 - 09-13-2021, 10:07 PM
RE: Stereo MPX Decoder for old Sony - by OZ4 - 09-13-2021, 10:35 PM
RE: Stereo MPX Decoder for old Sony - by OZ4 - 09-22-2021, 02:18 PM
toptip - by toptip - 02-12-2024, 02:13 PM
RE: Stereo MPX Decoder for old Sony - by RodB - 02-13-2024, 11:31 AM
RE: Stereo MPX Decoder for old Sony - by toptip - 02-13-2024, 11:46 AM
RE: Stereo MPX Decoder for old Sony - by toptip - 02-13-2024, 04:19 PM
RE: Stereo MPX Decoder for old Sony - by toptip - 02-14-2024, 12:23 AM
RE: Stereo MPX Decoder for old Sony - by toptip - 02-14-2024, 12:48 AM
RE: Stereo MPX Decoder for old Sony - by toptip - 02-14-2024, 12:54 AM
RE: Stereo MPX Decoder for old Sony - by toptip - 02-21-2024, 03:58 PM
RE: Stereo MPX Decoder for old Sony - by RodB - 02-21-2024, 04:48 PM
toptip - by toptip - 02-22-2024, 10:06 PM



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