Results 1 to 6 of 6

Thread: Rec freq off by .5

  1. Mon 17th May 2010, 23:17 #1
    ve7hfr
    ve7hfr is offline
    Join Date
    Apr 2010
    Location
    Osoyoos B.C. Canada
    Posts
    26

    Default Rec freq off by .5

    I recently bought this used Icom 735 and it works well. There is one annoyance however I'd like to fix.

    I notice when I tune a station the freq is usually in multiples of 10 for instance 14, 250.0 However I need to use the RIT function to get a clear receive audio. Or I need to change to 14,249.5 to get the same result.

    Is there an easy fix for this problem without test equipment ? I have not been employed as a technician since 1970 but am comfortable with the tools. A minor tweak is not a problem.

    Thnx
    DAve
    Reply With Quote Reply With Quote
  2. Tue 18th May 2010, 16:20 #2
    John_D
    John_D is offline
    Join Date
    Feb 2010
    Location
    Barnard Castle, UK
    Posts
    181

    Default

    On the ICOM 718, you simply press the "TS" button in again to change the tuning from 10 hz to 1 hz. It is alos possible to change the rate of tuning by the MENU.
    May be the same on the 735
    Reply With Quote Reply With Quote
  3. Tue 18th May 2010, 17:36 #3
    5B4AJB
    5B4AJB is offline
    Super Moderator 5B4AJB's Avatar
    Join Date
    Mar 2008
    Location
    Meneou, Cyprus
    Posts
    786

    Default

    Try tuning to a (WWV) frequency standard and see if it's your end that's off frequency.
    They are 5.0MHz 10MHz CW should beat at 0Hz (I think).

    Here's a link to the WWV pages:-
    http://www.nist.gov/physlab/div847/grp40/wwv.cfm
    Reply With Quote Reply With Quote
  4. Tue 18th May 2010, 23:52 #4
    ve7hfr
    ve7hfr is offline
    Join Date
    Apr 2010
    Location
    Osoyoos B.C. Canada
    Posts
    26

    Cool Wwv

    Okay, I tried WWV and my best audio is at 9.999.9

    I assume I need a receiver tweak.
    Reply With Quote Reply With Quote
  5. Wed 19th May 2010, 10:45 #5
    John_D
    John_D is offline
    Join Date
    Feb 2010
    Location
    Barnard Castle, UK
    Posts
    181

    Default

    With WWV you need to zero beat. That is tune down the tone until you hear nothing. Then you are on frequency.
    Reply With Quote Reply With Quote
  6. Thu 20th May 2010, 20:29 #6
    5B4AJB
    5B4AJB is offline
    Super Moderator 5B4AJB's Avatar
    Join Date
    Mar 2008
    Location
    Meneou, Cyprus
    Posts
    786

    Default

    OK, next round of questions...

    Is your local oscillator a heated oven type?
    Fluctuations in temperature will cause the L.O. to work at different speeds, multipy that up and you'll go a few Hertz off tune.

    I wouldn't bother with a few Hz, if it was more than, say, 3kHz, then it might cause a problem (DXcluster etc)...

    Anyway, here's a link, check out the Adjustments Procedures
    http://www.hampedia.net/icom/ic-735.php
    Reply With Quote Reply With Quote
« Previous Thread | Next Thread »

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Forum Rules