Jim McShane whereabouts

Discussion in 'Tube Audio' started by shelbygt, Jan 12, 2019 at 2:51 AM.

  1. shelbygt

    shelbygt New Member

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    Does anyone know what happened to Jim McShane? He seems to have dropped off Audiokarma and his old email address is no longer valid. I have a Sansui 1000A I'd like to restore and need caps, tubes, etc.
     

     

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  2. notdigital

    notdigital AK Subscriber Subscriber

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    No indication that he has dropped in here in years but hangs out regularly at AA. You can reach him here:

    Drop me an e-mail at jimmcshane@mcshanedesign.net ...
     
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  3. larryderouin

    larryderouin Turn it UP, POP? PLLUUEEEZZZZZEE Subscriber

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    +1 with George. Jim's site is http://www.mcshanedesign.net/tubes.htm

    As far as the 1000A goes, The Tung-Sol 7591A's (Russian Re-Issue) are a bit better than the EH's (smaller original size envelope) for temp control. If you can, implement the Power resistor mod I did back in 2013 ( http://audiokarma.org/forums/index.php?threads/1000a-power-resistors.536768/ ), and mount them in different places on the chassis. You will have about the same amount of heat overall, BUT it won't be concentrated between the Power Transformer, the 1st OPT and the one pair of OPT tubes. It'll run Warm overall, but no one area gets overly hot now.

    Can caps (200uf 250V x 2) can be stuffed with 470uf 400V or better Nichicon's, then CE CAN CAPS from Antique Electronic Supply
    For the 3 Section Can https://www.tubesandmore.com/products/capacitor-ce-mfg-525v-202020-f
    For the 4 section Can https://www.tubesandmore.com/products/capacitor-ce-mfg-525v-30202020uf The extra 10uf in the 1st section won't hurt it, but you'll need the Voltage rating to compensate for the higher line voltage of Today.

    Watch the Physical size of the Coupling Caps. they are .33uf @ 250V. Some brands like 715/716 Orange drops get quite large and are a PITA to shoehorn in. Suggest Russian K42 .33uf 400V as the maximum size to put in. Cornell Dublier DME Series are physically small, but I'm not crazy about how they sound in the coupling cap position in the 1000A. Illinois Caps MKP @400V are a good choice for the couplers. NO LESS but NO MORE THAN 400V here.

    The BIAS POTS should be replaced. They tend to get flakey.

    Grid return resistors NO MORE THAN 220K. Add 10ohm 1/4W resistor between the Cathode on the output tubes and ground. Add Screen Resistors (100ohm 1/4W) between pins 1 and 4 on each output tube then daisy chain the screen feed to each tube pin 1. Cut the jumper between the tubes from pin 8 to pin 4.

    And replace each and EVERY PIO CAP in the thing. SUZUKI Caps are crap, and tend to fireworks at this point in life. Even the ELNA's that might be in it are at the end and can blow. Use a good quality film cap (mix them up but use the same brand from left to right).

    6BQ8's can be replaced with 6DT8's (1/3 the price and are equivalent). Try not to use a 6DT8 in the Multiplexer. For some reason they don't like each other.
     
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  4. shelbygt

    shelbygt New Member

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    Thank you, gents! In my reading/ramblings, it sounds like there can be two or for bias pots. How do I determine this and where do I find schematics for the old girl?

    Serial number is 118040874.

    As a side note, how do I add an avatar and post pictures? Don't see an easy way to do this.
     
  5. notdigital

    notdigital AK Subscriber Subscriber

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    Top right. Click you name; click "personal details."

    Pics: Bottom right "upload a file" or thru "more options."
     
  6. larryderouin

    larryderouin Turn it UP, POP? PLLUUEEEZZZZZEE Subscriber

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    The Bias pots will either be 1, 2, or 4. IIRC my 2 pot unit had them in the one back corner. I know the 4 pot units are in the back corner under the phono preamp. Your's was manufactured during the 4th week of 1968. Quite possibly a 4 pot unit. I've got a schematic/manual on my desktop. I'll pull it up in the next 24 hours for you. Do note that there are at least 6 manuals/different schematics for the 1000A. The biggest changes are going to be in the tuner, and the Bias Circuits. The 1st iterations had a different tuner which was improved by the 2nd manual. (1965-66). The 4 pot version came out in 1967-68 but Sansui was very lax at making changes or just plain negligent. Anyway, I'll get the closest setup manual/schematic for ya. The bulk of the manual is the same across the lifetime of the 1000A except for the actual schematic. They even carried over the old NLA parts on the parts list. So don't be surprised if you can't find something on the unit that's in the parts list.
     

     

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  7. larryderouin

    larryderouin Turn it UP, POP? PLLUUEEEZZZZZEE Subscriber

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    Here's the 4 pot bias schematic. The manual @ hifiengine is the closest I've seen for the 4 pot unit, even tho the schematic in it is for the slightly older 2 pot version.
     

    Attached Files:

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  8. shelbygt

    shelbygt New Member

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    Wonderful. Thank you!! I'll look this over.
     
  9. shelbygt

    shelbygt New Member

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    Are there just 2 pages?
     
  10. shelbygt

    shelbygt New Member

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    So I took the covers off and discovered she's a 4 pot. Fired the old girl up about 2 hrs ago and I'm just taking it really easy with her. The pots and switches all need deoxit. Caps haven't blown yet. I should probably quit while I'm ahead.
     
  11. larryderouin

    larryderouin Turn it UP, POP? PLLUUEEEZZZZZEE Subscriber

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    Yeah, the HIFIENGINE cover page and the Sansui Schematic page. I'd check voltages for a baseline (write them down), then overhaul it. Take a picture of it underneath and post it. We're presuming that it's original and hasn't been touched..............YET!:naughty: This will verify need for overhaul or a refresh. (which may be a considerable cost difference.).
     
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  12. shelbygt

    shelbygt New Member

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    Wonderful! I have the 4 pot. Jim sent me a parts list, which also includes where they go. Will need help with bias and tuner adjustment.
    Is there a a way to post pics without having to subscribe to a hosting service?
    I'm going to subscribe to Audikarma. Great stuff.
     

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