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    Dynaco PAS/ Rotary Control New

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    Mark Korda

    Posts : 33
    Join date : 2009-12-29

    Dynaco PAS/ Rotary Control New

    Post by Mark Korda on Sun Apr 01, 2018 2:03 pm

    Hi, I am sort of restoring a Dyna PAS with the Last PAS mods by David Vorhis. It sounds real good as a friend had wired the circuit in. I have stripped it down and want to use some better parts in it. My question is about installing a new 6 pole 12 position rotary switch, the old rig has been taken out.
    Erhard audio has a wiring diagram where the high level wires, left and right go to the rotary switch. The ground wires from each high level input show no attachment. I don't know where to solder them but do know about making a ground lug bus terminal. Should I make one of those and position it near the switch and attach the high level grounds there?
    If I'm not seeing the easy answer I would love to know.
    I have a new gold jack set that has all the jacks grounded, except the phono, with a piece of metal embedded in the circuit board that you can see in good light. Is there something basic I'm not grasping?
    I will have all grounds connected to one point on the chassis, star ground. Thanks so much, Mark Korda 207-632-1648 (kordamark@gmail.com) P.S. Bob Latino recommended GP49 as the man to go to but I would like to hear from anyone who might know. If I can solve this I'm ready to solder....thanks again...Mark.

    starwatcher

    Posts : 11
    Join date : 2018-02-26

    Re: Dynaco PAS/ Rotary Control New

    Post by starwatcher on Wed Apr 04, 2018 1:44 pm

    Hello.

    I recently stripped a PAS 3 to the bones to rebuild it with new parts and follow the instructions of Erhart audio.
    I recommend you to print the schematics and take a good look at it even if the connections to the phono board will be different in the final.

    From the schematics all grounds of the high input of each channel must be connected together. After there's a 10 ohm resistor who go to the ground of the tape out and a solid wire to the ground of the audio out and finally both channels to the chassis.
    From this ground to the chassis you must put a wire to the ground of PC-5, soldering point #1.

    If you have build your RCA board like me you need to put a wire between soldering point #11 and #4 of PC-6 because phono ground is not common. Your RCA PCB have this connection.

    If i look to the Erhard audio RCA PCB board there's a connexion between tape in and tape out instead of the 10 ohm resistor of the schematics?

    Mark Korda

    Posts : 33
    Join date : 2009-12-29

    Re: Dynaco PAS/ Rotary Control New

    Post by Mark Korda on Wed Apr 04, 2018 4:58 pm

    Hi Starwatcher,
    thanks for your help. May you see a Nebula when your looking tonight.
    I have a diagram and a picture of the Erhard board that I got with the jack set. They both don't really show where the grounds go to near the rotary switch.
    In the instructions for the Last PAS they show this home made 5 prong ground lug. The 2 and 4th lug are snipped off to solder a wire across 1 and 5. It's attached to the chassis with 1 screw. The Last PAS instructions were given to me on line. There is a good drawing of that ground.
    I think you would love to read that article. If I can't figure out how to get it on this forum this is what you do. Go to Audio Asylum, then Vintage, and scroll down to PAS-2(Mark Korda). Start reading and some good fellow left the whole article(LastPAS).

    Mine will differ from the Erhard, and I would love an Erhard. It's just a project thats bettering parts on a circuit that worked real good that a freind made...that I still keep in touch with. A friend just called and said he was on the way so I have to cut this short...but I got some more to run by you....thanks Starwatcher...Mark.

    Mark Korda

    Posts : 33
    Join date : 2009-12-29

    Re: Dynaco PAS/ Rotary Control New

    Post by Mark Korda on Wed Apr 04, 2018 6:21 pm


    Mark Korda

    Posts : 33
    Join date : 2009-12-29

    Re: Dynaco PAS/ Rotary Control New

    Post by Mark Korda on Wed Apr 04, 2018 6:23 pm

    Starwatcher, that link I posted was the Last PAS......Mark...copy and paste worked!

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    Re: Dynaco PAS/ Rotary Control New

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