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Kenwood 990 Coming Next Month


I see on the link it uses 50V fets driven to 200w for the finals. I wonder what power supply it uses. The FT1000 is awkward to get a power supply for as it gives several different voltages as well as 48v I hear. If this radio could be used with a server psu it wouldnt be too bad because we all know power supply units dont last forever and are a common source of trouble.
 
The TS-950SDX also uses power MOSFETs: Motorola MRF150s, also run at 50 volts (well, 48 volts, but close enough). That radio is designed for 150 watts rather than 200, but the VRF150 is a heavier duty part. According to Kenwood's literature, it was the first HF amateur rig to use FETs intead of BJTs in the transmitter, and it offered a lower distortion output as a result.

The power supply in the 950SDX is linear style (as opposed to switching) with two different transformers and several different regulators and output voltages: 50v for the finals, plus 15v and several 5v outputs. I think there's one negative voltage for the florescent display tube too.

The transformers account for much of the radio's weight: it's nearly 60lbs. I hope for the 990 they switched to a switching style supply, though with everything else they crammed into it it's probably still going to be pretty hefty.

-Bill

Added:

Oh, derp, the description at the Kenwood link says it does have a switching power supply.
 

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  • @ heartbreaker3473:
    Hello gentlemen and Ladies. I have the dreaded RCI-2990 receive issue where my radio gets distorted when people get close to my location. I found the C90 Capacitor, but I can not for the life of me find the C89 capacitor. Can or does anyone have a picture of the exact location of C89 ? Thank you in advance, Wes
  • @ AudioShockwav:
    Wes, it's better if you start a thread on the main forum, more people are going to see your question.
  • @ heartbreaker3473:
    Okay, sorry, will put in a forum
  • @ heartbreaker3473:
    I put it in the general disscution help area and started a new thread. Thank you for letting me know.