1. You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
    Dismiss Notice

Connex 4300 anyone see this hack before?

Discussion in 'General CB Services Discussion' started by Low_Boy, May 5, 2018.

  1. Low_Boy

    Low_Boy Active Member

    Joined:
    Jan 21, 2010
    Messages:
    335
    Likes Received:
    66
    A NEW HACK I never saw until today.


     

    Attached Files:


  2. ShadeTreeMechanic

    ShadeTreeMechanic 808 On The North Side of Dover

    Joined:
    Oct 23, 2017
    Messages:
    406
    Likes Received:
    196
    Is that part of a swing mod?
     
  3. Handy Andy

    Handy Andy Active Member

    Joined:
    Apr 23, 2018
    Messages:
    183
    Likes Received:
    64
    No, not swing, ripple filter. The Emitter and Collector - offset by a cap - DC arrives in and audio + DC passes out.

    Wiki has got some help to it
    https://en.wikipedia.org/wiki/Ripple_(electrical)#Frequency-domain_ripple


    Why? It's used to smooth harsh ringing effects from switching noises - ripple to remove noise (judging by cap values) about 2kHz and higher - to DC - it's like using a cap to shunt to ground - you can do the same thing but make it to the plus rail (Battery DC)

    Regards!
    :+> Andy <+:
     
    ShadeTreeMechanic likes this.
  4. Low_Boy

    Low_Boy Active Member

    Joined:
    Jan 21, 2010
    Messages:
    335
    Likes Received:
    66
    I removed it. Do you think it should go back. The radio had all kind of swing mods that I removed. I do not have to ask if I should put them back. LOL
     
  5. Handy Andy

    Handy Andy Active Member

    Joined:
    Apr 23, 2018
    Messages:
    183
    Likes Received:
    64
    If it doesn't affect your tone or maybe you like the tone now, all it was, or functions as, a high-cut smoothing filter - kinda' takes the high end (upper audible range) "Snaps" that may occur during switching loads - rounds off their "edge" into a curve. Much like ANL filter caps.

    You'd be better off swapping that out - the Mylars are common, but not indestructible. Considering their construction - can be subject to damage from vibration, pressure/stress and they use "aluminized paper" a lot like the Electrolytics do, only without the electrolytic (no galvanic effects) - the size of it - I guess the value to be between 0.22uf (224) or 0.1uF (104) these are not polarized so they can be swapped with ceramic discs if you have spacing issues.

    Regards!
    :+> Andy <+:
     
  6. kaos513

    kaos513 Well-Known Member

    Joined:
    Apr 10, 2014
    Messages:
    1,184
    Likes Received:
    174
    I think its to make the modulation more clear.
     
  7. Low_Boy

    Low_Boy Active Member

    Joined:
    Jan 21, 2010
    Messages:
    335
    Likes Received:
    66
    It is not my radio it belongs to someone I work with. Radio had all kind of problems I just straightened it out for him. I nerver ran with him but the other drivers said it sounded bad most of the time. I think it sounds pretty good now. Now I can get back to working on my cobra 29.
     
    ShadeTreeMechanic likes this.
  8. nomadradio

    nomadradio Analog Retentive

    Joined:
    Apr 3, 2005
    Messages:
    1,426
    Likes Received:
    874
    Don't know the value if the green capacitor, but if you listen to this radio's transmit audio on another radio, you can decide if it changes the sound for better or worse.

    Pretty sure all it should do is reduce the treble response.

    Maybe enough to hear the difference, maybe not.


    The factory puts a 0.1uf (104) capacitor (C212) on the top side of the pc board across the same spot. If it has been removed, you might want to leave this one where it is.

    73
     
  9. Onelasttime

    Onelasttime Well-Known Member

    Joined:
    Aug 3, 2011
    Messages:
    761
    Likes Received:
    319
    I use a stock radio with no antenna to listen to the on air sound of a radio I have repaired. No amount of rf sampling matters if it does not sound good on the rx end of a stock radio for me. I know that is ultra low tech and not at all empirical since it does not generate a number or other such measurement that I can correlate and record. Although ultimately since we listen to the radio with our ears it is a valid validation process once you think you have all your ducks in a row. Kind of like shooting a rifle versus looking at it's barrel with a borescope. Ultimately the true test is in the shooting of the rifle not how pretty the bore might look!

    Put another way I have seen some beautiful trumpets that played like dogs! Audio amps that looked great on test gear but sounded terrible! Sometimes the practical is more important than appearances or less than dynamic test conditions! We do at times get caught up in the technical and we forgot about the practical basis of our hobby!

    When it comes to modifications one well thought out and a well-executed mod can be worth far more than many poorly done modifications. Often times more is not better with a good many things. The prob. is that just because someone can hold a soldering iron and put parts on a board does not mean they understand what they are doing and why! Without understanding no matter how well the parts are placed on the board and joined to the rest of the circuit the end result will seldom be anything of value unless it happens by happy accident! LOL If one does not have the gear to see the results of ones work how can you predict and repeatedly get the result you want?
     
  10. Low_Boy

    Low_Boy Active Member

    Joined:
    Jan 21, 2010
    Messages:
    335
    Likes Received:
    66
    If I ever get some time I will experiment with this on one of my radios. That radio belonged to someone I work with and I gave it back already. That radio will probably never sound good lol. Way too many hacks have been in it. But atleast now it is working and the modulation looks a bit better.
     

Share This Page

  • About Us

    The WorldwideDX Radio Forum was originally established in 2001. We pride ourselves on welcoming Radio Hobby enthusiasts of all types, while offering unbiased, informative, and friendly discussion among the members. We are working every day to make sure our community is the best Radio Hobbyist's site.
  • Like us on Facebook

  • Premium VIP Member

    The management works very hard to make sure the community is running the best software, best designs, and all the other bells and whistles. Care to buy us a beer? We'd really appreciate it!

    Donate to us!