WRL Globe Champion 350A

Discussion in 'Amateur Radio' started by WB6KWT, Sep 17, 2017.

  1. WB6KWT

    WB6KWT Member

    I picked up a Champion 350A a few years ago and started replacing some caps and the selenium rectifiers. I used 1N4007 diodes to replace the selenium rectifiers. I now understand I should have included a resistor in series with the diode because of the increase in line voltages today. Anyone know the values of the various resistors/wattage. I should have taken voltage readings before removing the selenium diodes but I didn't.

    Bob -wb6kwt
  2. WQ5Q

    WQ5Q Member

    I really like the looks of the Globe Champ. I've been working on an old Viking II with the similar issue of higher voltages. It seems to work fine on the higher AC line voltage. But I am restoring it and making an overhaul of the audio section. I also have a Globe King 500 needing restoration that I'll eventually get around to.

    Looking at the schematic for the 350, there is one selenium rectifier SR3 used in the grid bias circuit to half wave rectify the nominal "110 AC" off the power transformer. That's followed by a voltage divider network to tap off the various necessary voltages ranging from -100vdc to -8vdc. The bias voltages are shown on the schematic and on the "typical voltage" table in the manual. Why not just check the actual voltages you have now against the values in the manual as a place to start? You may need to tweak the resistor values in the voltage divider to get back in line. Since you are reworking the "Chump" you should check these voltages anyway, right? Some of the resistors may be off causing the voltages to be off. Good luck...seems you have a nice AM rig there. Does it still have the AX 9909's in the final?
  3. WB6KWT

    WB6KWT Member

    Thanks for the reply Kelly, I've just got my Johnson Valiant back into it's case and will see if I can muscle the 350 up on the bench, it's a little heaver than the Valiant. When I got the rig one of the AX 9909's was broken so I haven't done anything about replacing the PA tubes with something else. I have the original manual but danged if I can find it but I do have a copy from BAMA. I have a Viking II that a fellow was in the process of changing the front panel so at the moment it's a project too, along with a couple of 122 vfo's.
  4. WQ5Q

    WQ5Q Member

    Wow....didn't realize there were table top transmitters heavier than the Valiant. Sounds like you have plenty there to keep you busy.
  5. W6MQI

    W6MQI Member

    I had to look this one up I've never heard of the Globe Champion 350 before gotta say that is a nice looking rig you have there Bob, downloading manual now for a look.

    Looks to be 105lbs with a shipping weight of 120 lbs he's going to need a crane to get that beast on his steel reinforced bench:mrgreen:
  6. WD5JKO

    WD5JKO Member

    Attached Files:

  7. WB6KWT

    WB6KWT Member

    Thanks for all the replies, these led me to search for a replacement for the AX9909 which took me to a discussion on amfone, some good information there.
  8. WD5JKO

    WD5JKO Member

    I once converted a Globe Champ 350 to using a pair of 4-65 finals. The AX9909's had turned whit inside. The 809 modulators were missing, so instead I used a pair of 808's there. Several engineering issues to overcome with those changes. The cool thing of using the 4-65's is that the DC input and RF output was the same on all bands, 160-10m. If interested I could describe the low and high points of that conversion.