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Repair and Restoration => Solid State Consoles => Topic started by: MagMan on June 19, 2016, 07:14:43 PM

Title: Testing Packaged Components (Packaged Resistors)
Post by: MagMan on June 19, 2016, 07:14:43 PM
Would someone please educate me on how to test a packaged component? I'm working on a Magnavox AstroSonic chassis that has 4 of these PCs. Attach are a couple of pictures.  How do you replace them if one or more of the components test bad? Any pictures you might have would be most appreciated.
Title: Re: Testing Packaged Components (Packaged Resistors)
Post by: electra225 on June 19, 2016, 08:07:42 PM
I believe what you are referring to is what I call a couplet.  The only way I know of to replace one, other than finding a good original, is to replace the discreet components on a wafer board and use that in place of the couplet.  I'm not claiming that they NEVER go bad, but I personally have never found a bad one. 
Title: Re: Testing Packaged Components (Packaged Resistors)
Post by: Consoleman on June 20, 2016, 09:04:37 AM
You can check a resistor in place and it shouldn't read any higher than its value. If it reads lower, the multimeter may just be finding a different path through the circuit.
Title: Re: Testing Packaged Components (Packaged Resistors)
Post by: AstroSonic100 on June 20, 2016, 03:59:52 PM
I believe what you are referring to is what I call a couplet.  The only way I know of to replace one, other than finding a good original, is to replace the discreet components on a wafer board and use that in place of the couplet.  I'm not claiming that they NEVER go bad, but I personally have never found a bad one.

The couplet for the audio section in my early 50s Sparton portable radio must have failed at one time.  It looks like a cap and resistor inside the Couplet had failed.  The couplet was still connected to the circuit except for the leads going to the bad cap and resistor.  The person doing the repair did a work around by installing a new cap and resistor and connecting them in the conventional way.