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Parasitic suppressor specifically for SB-200

Discussion in 'Amateur Radio Amplifiers' started by K3HMG, May 3, 2021.

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  1. K3HMG

    K3HMG Ham Member QRZ Page

    @WB2WIK Before making the Modifications to this amplifier mentioned in previous posts I’m gonna run her like she is in order to identify any potential issues before the mods are made.

    In looking more closely I identified that one of the parasitic suppressors legs Solder joint was cracked so I decided to give the suppressors a closer look and in doing so I found one of the resistors to be reading high at around 65 ohm the particular resistors they are currently in the amp or 47 ohm 2w resistors. I’m going to go ahead before I even power her up and replace the parasitic suppressors

    I found a suitable replacement for the resistors but my question is what gauge wire Should be used for the coil? I will be using 572b tube. I have read several that the diameter should not be changed. I am not sure if these are original suppressors and I am wanting to rebuild to original spec. That in advance

  2. W1QJ

    W1QJ Ham Member QRZ Page

    I make mine with #16 wire but you could use #14 too. It’s not that critical. As long as it’s not other than those two sizes.
    WQ4G, KU3X and K3HMG like this.
  3. K3HMG

    K3HMG Ham Member QRZ Page

    awesome thank you
  4. K3HMG

    K3HMG Ham Member QRZ Page

    I have some 14ga enameled wire. Could I use that and just clean the enamel off where I solder it to the resistor legs? Will the enamel coating diminish the intended effect? Or will it simply melt off over time?
  5. KP4SX

    KP4SX Premium Subscriber QRZ Page

  6. K3HMG

    K3HMG Ham Member QRZ Page

    What type of wire to connect to the plate choke. Nichrome? Tinned copper? The enameled wire I have? What is the best way to connect? When I removed the damaged ones everything was soldered in.
  7. AC0OB

    AC0OB Platinum Subscriber Platinum Subscriber QRZ Page

    I use #16 tinned buss wire but but I don't see where enameled wire would not work if the ends are cleaned so you can solder them to the resistor.

    K3HMG likes this.
  8. W1QJ

    W1QJ Ham Member QRZ Page

    enamel will work but clean the soldered area well
    KU3X and K3HMG like this.
  9. K3HMG

    K3HMG Ham Member QRZ Page

    How about the leads to the plate choke?
  10. W1QJ

    W1QJ Ham Member QRZ Page

    also 16 or 14.
    K3HMG and KU3X like this.

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