The Dynaco Tube Audio Forum

Dedicated to the restoration and preservation of all original Dynaco tube audio equipment - Customer support for Dynaco VTA tube amp kits, all Tubes4hifi.com products and all Dynakitparts.com products


    Oh Henry!!!!

    Share

    Captain Coconut

    Posts : 213
    Join date : 2009-10-13
    Age : 64
    Location : Great White North

    Oh Henry!!!!

    Post by Captain Coconut on Sat Jul 18, 2015 10:38 am

    It has been documented that it is advisable to change out the 50 ohm resistor after the first cap in the Dynamo ST-35 power supply with a choke. Most of the chokes I have seen are 200mA-250mA and 1.5H. This is supposed to aid in reducing ripple current. (Adding more capacitance in the power supply would help too.)

    How about adding a choke with 4H instead? If the other parameters are the same, will the increase in inductance help even more? Can you have too much inductance?

    Tubes4ever

    Posts : 61
    Join date : 2015-07-14
    Location : Star, Idaho

    Re: Oh Henry!!!!

    Post by Tubes4ever on Sat Jul 18, 2015 11:37 am

    4H will work fine. Do you already have the choke?  Make sure it will handle the current.  Also replacing the 50 ohm resistor with the choke will change your B+ since the DC resistance of the choke will be different from the resistor.  You may need to add a resistor in series to keep the B+ from going above its current level.  Most old tube circuits recommended at least 4H, so you are safe.

    Captain Coconut

    Posts : 213
    Join date : 2009-10-13
    Age : 64
    Location : Great White North

    Re: Oh Henry!!!!

    Post by Captain Coconut on Sat Jul 18, 2015 3:10 pm

    Thanks Tubes Smile

    Sponsored content

    Re: Oh Henry!!!!

    Post by Sponsored content Today at 11:57 pm


      Current date/time is Wed Dec 07, 2016 11:57 pm