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    use caution when adding PIO caps into your amplifier

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    tubes4hifi
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    use caution when adding PIO caps into your amplifier

    Post by tubes4hifi on Thu Mar 07, 2013 8:45 pm

    to many people this is obvious, but unfortunately not everyone knows as much as they should.
    When using the Russian PIO K40-Y capacitors that Bob and I offer as an option, make sure they are insulated from the rest of the circuit,
    from the circuit board, and any surrounding parts, such as the front octal sockets where you check bias.
    I supply them with electrical tape on the bottom side, and heat shrink for the leads. Bob supplies heat shrink for the leads, but I'm not
    sure if anything else. I now also stock heat shrink tubing (3/4" size) to completely enclose them.
    The body of the capacitor is metal. If it touches anything else, something will short. Leave the leads long enough to space them away from
    the PCB and away from the front octal sockets.
    The first photo below shows stick-on tie-wraps to hold them away from the board and in place.
    I couldn't' find any photos I had where it was obvious I had electrical tape on the bottom side,
    the 2nd photo (it's the octal version) below shows where I fixed an amp that had a cap shorted to both the PCB and the front socket.
    The leads were too short to space it up more, but I managed to squeeze some (white) electrical tape under it and in front of the octal socket.





    arledgsc

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    Location : SF Bay CA

    Re: use caution when adding PIO caps into your amplifier

    Post by arledgsc on Sat Mar 09, 2013 12:47 pm

    Good suggestion. I am amazed at how much the Russian PIOs weigh. Several ounces each it seems. If not secured it is a lot of mass suspended by only the two skinny leads. But I like the tie-wrap sticky idea and anchor them to the board. Would be most worried about shipping the completed amp with unsecured caps. They could vibrate during shipping and break a lead or end up shorting to the board. To answer your question my ST-120 kit from Bob only had the tubing for the leads.

    mike mytko

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    Age : 47
    Location : Bowmanville, Ontario, Canada

    Re: use caution when adding PIO caps into your amplifier

    Post by mike mytko on Sun Mar 10, 2013 9:11 pm

    Hey
    The picture with the panduit stickies is my build! I got the idea from another piture somewhere.
    Mike

    Windup

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    Re: use caution when adding PIO caps into your amplifier

    Post by Windup on Mon Mar 11, 2013 5:51 pm

    Just purchased the PIO optional caps with my VTA and received large shrink wrap tubing for the caps. Great idea! Someone is listening....

    tubes4hifi
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    Re: use caution when adding PIO caps into your amplifier

    Post by tubes4hifi on Mon Mar 11, 2013 6:01 pm

    Windup,
    "Say Anything" ! classic movie moment!

    Windup

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    Re: use caution when adding PIO caps into your amplifier

    Post by Windup on Mon Mar 11, 2013 7:03 pm

    What song was the boom box playing, in this photo?

    tubes4hifi
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    Re: use caution when adding PIO caps into your amplifier

    Post by tubes4hifi on Mon Mar 11, 2013 7:24 pm

    In Your Eyes - by Peter Gabriel

    Windup

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    Re: use caution when adding PIO caps into your amplifier

    Post by Windup on Mon Mar 11, 2013 8:48 pm

    I love it!

    Sprags

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    Join date : 2013-02-27

    Re: use caution when adding PIO caps into your amplifier

    Post by Sprags on Thu Mar 14, 2013 10:10 pm

    arledgsc wrote:Good suggestion. I am amazed at how much the Russian PIOs weigh. Several ounces each it seems. If not secured it is a lot of mass suspended by only the two skinny leads. But I like the tie-wrap sticky idea and anchor them to the board. Would be most worried about shipping the completed amp with unsecured caps. They could vibrate during shipping and break a lead or end up shorting to the board. To answer your question my ST-120 kit from Bob only had the tubing for the leads.

    I'm having an amp built for me from Bob's technical crew. I'm wondering if it wouldn't be prudent of me to check the PIOs to make they haven't shifted during shipping.

    Windup

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    Re: use caution when adding PIO caps into your amplifier

    Post by Windup on Fri Mar 15, 2013 7:40 am

    I don't think that would be an issue but, always a good idea for your oun peace of mind. Besides, you'll get to to see Bob's quality handy work.

    DarthBubba

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    Re: use caution when adding PIO caps into your amplifier

    Post by DarthBubba on Fri Mar 15, 2013 11:57 pm

    Windup wrote:I don't think that would be an issue but, always a good idea for your oun peace of mind. Besides, you'll get to to see Bob's quality handy work.

    Bob's handiwork isn't the issue. It's the handiwork of the delivery service that warrants cautious inspection before slipping the blue spark into the glassworks. Mustn't allow the magic smoke to get out. No

    -DB

    Sprags

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    Re: use caution when adding PIO caps into your amplifier

    Post by Sprags on Sat Mar 16, 2013 12:56 am

    DarthBubba wrote:
    Windup wrote:I don't think that would be an issue but, always a good idea for your oun peace of mind. Besides, you'll get to to see Bob's quality handy work.

    Bob's handiwork isn't the issue. It's the handiwork of the delivery service that warrants cautious inspection before slipping the blue spark into the glassworks. Mustn't allow the magic smoke to get out. No

    -DB

    Exactly...you never know if a package was handled with enough care to prevent damage.

    I was actually thinking of a way to put some kind of non conductive spacer under the PIO that doesn't take away from the appearance of skilled craftsmanship in the assembly process.

    Windup

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    Re: use caution when adding PIO caps into your amplifier

    Post by Windup on Sat Mar 16, 2013 8:18 am

    My point exactly! Bob's handiwork is never an issue,
    That's because he takes fine care in the build as well as, packing in a practically bomb proof box. It's refreshing to admire compared to some of the knuckleheads who send delicate audio gear wrapped in old newspapers and thrown into a box.

    arledgsc

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    Re: use caution when adding PIO caps into your amplifier

    Post by arledgsc on Tue Mar 19, 2013 11:16 am

    Another option is electronics grade RTV silicone. I may not have room for the cable tie spacers on my already built ST-120 so exploring options. With a little practice you can surgically squeeze a little dab of RTV under the parts and have a stealthy looking application. After drying RTV is flexible so adds some shock absorption as another benefit. If you make a mistake let it dry and remove the excess with an X-acto knife.

    WARNING: I would like to stress you need electronics grade RTV. Standard silicones like tub and tile calk are corrosive. Most are so read the label thoroughly before venturing down this path.



    Here's a datasheet for Loctite 5145 mil spec RTV. It is generally expensive but some guy on Ebay is selling tubes for $8.99 including US shipping. If you find any brand less costly let us know.
    Loctite 5145 Datasheet


    Last edited by arledgsc on Tue Mar 19, 2013 4:52 pm; edited 2 times in total

    Sprags

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    Re: use caution when adding PIO caps into your amplifier

    Post by Sprags on Tue Mar 19, 2013 11:43 am

    Using the RTV Silicone as a solution to ensure specing between the PIO cap and the board as well as adding a bit of shock absorption is an excellent suggestion. Here is Cincinnati we have a Microcenter computer store and I bet they probably have electronics grade RTV silicone there.

    Thank you...Blake

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