NEED HELP TO REPAIR ICOM R7000 RECEIVER

Discussion in 'General Technical Questions and Answers' started by KT1R, Dec 11, 2019.

ad: L-HROutlet
ad: l-rl
ad: Left-3
ad: L-MFJ
ad: Left-2
ad: Subscribe
ad: MessiPaoloni-1
  1. KT1R

    KT1R Ham Member QRZ Page

    Hi, Please advise if you know of someone who can repair this R7000 receiver. Icom does not support it.
    Radio does not power up completely. The meter backlight does light, but display does not come up.
    I really like this radio and do not have test equipment to troubleshoot it.

    Call me at 240-382-2847 or email n9kc88@gmail.com

    TNX es 73 de KT1R Lou in West Virginia
     
  2. N8YX

    N8YX Ham Member QRZ Page

    C19 and C20 on the Display board (behind the front panel) form part of a DC-DC converter circuit which supplies negative voltage for the rig's VFD tube. These are 10uF and are under-rated (voltage wise) for the application. In time, they will fail and cause the issue you're describing.

    Replacement with a 25v, 105c rated part will cure the fault. There is a lot of data regarding this condition and the fix on the 'Net.
     
    AA4MY and W6KCS like this.
  3. W6KCS

    W6KCS Ham Member QRZ Page

    N8YX: We have one or two in our test equipment collection that have this symptom, I'll see if this is the problem. Thanks for the tip!
     
  4. N8YX

    N8YX Ham Member QRZ Page

    I have six of the things.

    Three are fully functional at this point and three are in Ye Olde Project Pile for assorted R&R work. All have had the display failure.

    There's also a well known/documented problem with loss of sensitivity caused by the failure of yet another electrolytic capacitor. At least half of mine have had this issue fixed.

    FWIW, mine operate 24x7 and are powered from a Big Honkin' Regulated DC Supply via a Rig Runner. Those that are cured of factory evils tend to stay cured and stay working.

    Another tip for those who don't mind playing with a soldering iron and a Dremel tool:

    Remember the Murata CFJ455K- series filters...as are used in many solid-state SSB rigs in the transmit path? These can be had in a number of bandwidths and shape factors. Every time I get a handful of 2.4KHz and 4-6KHz parts I remove the stock SSB and AM filters from one of my R-7000's IF Units, mod the board to accept the larger filters then install them. Performance on SSB and AM is MUCH better.

    Two of mine also have internal ADSP units (SGC). The NR function and B/W selection is controlled by the front-panel "Speech" button.

    Look around the 'Net for mod details. I've documented this elsewhere with pictures and someday will upload the info to the Groups.io 'R7000-RX' group.
     
    W6KCS likes this.

Share This Page

ad: M2Ant-1