ad: UR5CDXcom-1

Kenwood TS-440 problems

Discussion in 'Radio Circuits, Repair & Performance' started by K6DWI, Dec 17, 2013.

Thread Status:
Not open for further replies.
ad: L-HROutlet
ad: l-assoc
ad: l-gcopper
ad: l-sarc
ad: l-innov
ad: l-rl
ad: L-rfparts
ad: Subscribe
  1. K6DWI

    K6DWI Ham Member QRZ Page

    Hello everyone,

    I have a Kenwood TS-440s that was working fine one day and the next I have no audio,
    the transmit light is on (but not transmitting).
    If I key up or send it appears to have power out.
    Display, auto tune, channel, and mode seems fine.
    Can someone help me diagnose the problem?

    Thank you
  2. G4COE

    G4COE Ham Member QRZ Page

    What about SSB receive is that OK?

    How about the mic. gain control? Trying another mic, might as well try the AM mode as well - more clues the merrier.

  3. VE1IC

    VE1IC Ham Member QRZ Page

    is the rx and tx light on both at the same time?
  4. K6DWI

    K6DWI Ham Member QRZ Page

    Checked all controls, tried another mike, tried all modes.
    Does not appear to receive (no sound, no meter movement)
  5. K6DWI

    K6DWI Ham Member QRZ Page

    transmit light on all the time when powered up, (no rx light)
    No rx meter movement on known transmitted channels
  6. VE1IC

    VE1IC Ham Member QRZ Page

    check the rxb and txb voltage. If RX the rxb buss voltage should be 8v. When TX the txb voltage should be 8V on the main board. Should be either or, but not both at the same time. If you get something like 4V or so, something is leaking. What is the current draw? Lock at the RX/TX switching IC or transistors see if they are not shorted. Kinda beats me why it doesn't actually engage the finals...
    It can't RX, because it is stuck in TX. Only thing that stumps me on top of my head is why it isn't actually transmitting through the finals. You can easily check that whats going on with a oscilloscope. I didn't see the schematic yet.
  7. K3LFC

    K3LFC Ham Member QRZ Page


    chris...chris....I had a kenwood ts 440s.....RANGER!!! I use ranger 2950dx with an amp.....Its great!!!!!

    Goto copper electronics online.....Have fun dxin !

    k3lfc Frank Caruso IV wilm de U S A

  8. N9DSJ

    N9DSJ Ham Member QRZ Page

    Errr...never mind
  9. N9DSJ

    N9DSJ Ham Member QRZ Page

    Have you tried with no mic, nothing in the CW key jack and any acc plug removed? Sounds like it is stuck in tx mode as was previously said.
  10. K6DWI

    K6DWI Ham Member QRZ Page

    I unplugged mike, nothing in the CW or ACC
Thread Status:
Not open for further replies.

Share This Page

ad: elecraft