1. In celebration of the launch of the new redesigned site, we just gave away a FREE antenna! Click Here to See Who Won!

tuning cobra 2000 gtl

Discussion in 'General CB Services Discussion' started by excavator701, Apr 16, 2006.

  1. excavator701

    excavator701 Member

    Joined:
    May 23, 2005
    Messages:
    88
    Likes Received:
    0
    i just aquired a 2000 gtl i know the am carrier is vr10 and modulation is cut 131 but what adjust the pep rf output can anybody help please


     
    #1
  2. Switch Kit

    Switch Kit Active Member

    Joined:
    Apr 6, 2005
    Messages:
    3,517
    Likes Received:
    11
    sure thing ,but do yourself a favor and dont cut r131 , you don't need to do a lot for those radio to sound awesome , Modulation to 100% is all you really need on those which is VR12 /AMpower is VR10 /and SSB power is VR11
     
    #2
  3. Thestonerguy

    Thestonerguy Active Member

    Joined:
    Apr 3, 2005
    Messages:
    338
    Likes Received:
    0
    The 2000 will sound great with an amplified mike like the Turner Plus3. Please don't cut the limiter....
     
    #3
  4. TonyV225

    TonyV225 Supporting Member

    Joined:
    Apr 18, 2005
    Messages:
    5,749
    Likes Received:
    251
    dont cut anything alot of times it makes your sideband or modulation uncontrolably wide open heres what you need....VR7 AM MODULATION set this at 100%....VR11 SIDEBAND RF POWER generally they hit about 22-23 watts just set to 20 watts....VR10 AM RF POWER you need to watch this setting some of those power supplies were weak or just enough to run the radio even the sideband at 20 watts will draw on that power supply watch for lights dimming. if you see light drastically dim then best thing to do if you insist the higher power output is to run that radio on an external power supply a 6-10 ampre is plenty and very reasonably priced and the radio will run smoother at pep .you may also see and hear the rf power meter slamming the fullscale side after turning power settings up to avoid trashing that meter adjust VR6 for a safe fullscale reading.. These should get you going on the right track if you need any frequency adjustments just post it here and ill help but i dont suggest messing with any vco's or cans unless you have the propper equipment or are absolutely sure about what you are doing
     
    #4
  5. excavator701

    excavator701 Member

    Joined:
    May 23, 2005
    Messages:
    88
    Likes Received:
    0
    cobra 2000 tuning

    i appreciate thge help my question is i am only getting 15w pep is there some thing in the radio to adjudt for max pep the only info i can get on the net is what i posted cant find nothing for pep adjustment
    thanks again!!!!!!!!!
     
    #5
  6. Switch Kit

    Switch Kit Active Member

    Joined:
    Apr 6, 2005
    Messages:
    3,517
    Likes Received:
    11
    What kind of meter are you using ? and is that off a dummy load or the antenna ? 15 watts pep on AM for that radio is not far off course , should do 18 to 20 on SSB ,don't under estimate that 2000 , as I said before ,they don't need very much done to them for them to perform well .
     
    #6
  7. excavator701

    excavator701 Member

    Joined:
    May 23, 2005
    Messages:
    88
    Likes Received:
    0
    cobra2000gtl tuning

    i undrstand all that and i appreciate the help but is there a pot in the radio that can be turning for max pep??????????
     
    #7
  8. excavator701

    excavator701 Member

    Joined:
    May 23, 2005
    Messages:
    88
    Likes Received:
    0
    cobra2000gtl tuning

    i undrstand all that and i appreciate the help but is there a pot in the radio that can be turning for max pep??????????
     
    #8
  9. Switch Kit

    Switch Kit Active Member

    Joined:
    Apr 6, 2005
    Messages:
    3,517
    Likes Received:
    11
     
    #9
  10. TonyV225

    TonyV225 Supporting Member

    Joined:
    Apr 18, 2005
    Messages:
    5,749
    Likes Received:
    251
    how did this turn out?? I am actually putting another one of these together also and i was wondering how your was coming or turned out there great little radios..
     
    #10
  11. excavator701

    excavator701 Member

    Joined:
    May 23, 2005
    Messages:
    88
    Likes Received:
    0
    cobra 2000 tuning

    it seemed to turn out ok i have had good results and everybody has told me the audio is outstanding i could only seem to get about 18pep max theres really not many adjustments in that radio to make it better i am still going to bring it to my tech and let him look at it the radio still has some issues when i got it it seems like the ac side of it wont work i am useing the dc side off a battery that might be another reason why im not getting better wattage we will find out though thanks to everybody for the help
     
    #11
  12. Switch Kit

    Switch Kit Active Member

    Joined:
    Apr 6, 2005
    Messages:
    3,517
    Likes Received:
    11
    power supplies in those have been known to fail after years of service , The Cobra 2000 basically came out in 1979 and had a production run until 1993 ,parts are getting slightly harder to come by and can be exspensive when found , I always thought they were pretty radios and I must admit ,they performed very well. 18 watts pep is about right 701 , most AM/SSB CB radios should do about the same on AM and SSB (give or take a watt either way) it's great that you can run a power supply to yours to make it run (-: it could be a number of things why your internil is not working. Over the years the basic things I've personally seen go wrong with those first was the AM voltage regulators go out on them , in other words , the AM side of the radio dies but SSB continues to work fine ....easy fix (-: new reg and your back in business. Power supplies getting weaker and weaker as time goes by , keying down and modulating you can pretty much see the piower dimming in all your light works in the radio , the way to tell this is to hook up a good 10 amp power supply to the dc side of the radio , if all lights up nice and healthy and stays that way after keying and modulating , that should be a pretty good indication about the on board power supply )-: , Freq counters going bannanas !!! there is a fix for some ,but most need new panels )-: now were talking a little cash if we can find one to replace it with. Like I said before , the wonderful thing about a C-2000 is there's not a lot you need to do to them for them to sound very nice on the air. It's your time and your dime after the fact. I hope the tech don't charge you an arm and a leg there 701 ? Personally ,nowadays , I think I would try and keep it simple when it would come to a older base station , The 2000's have become pains in the dairy airs for many but not for all , there were a lot of good low maintance radios out there like the 142s that you wouldn't have to worry about things going out on them as you would the 2000s some 25 years later or depending on how old the radio was in the first place. I suppose if it were me today ,I'd rather just go with a 20 some year old 148 GTL (same as the 2000) with a good power supply with less problems to worry about or deal with later on.I truly wish you the best of luck with your 2000 and I hope it can all be put back the way it should be and that you will be very pleased in the end. Have fun. (-:
     
    #12
  13. excavator701

    excavator701 Member

    Joined:
    May 23, 2005
    Messages:
    88
    Likes Received:
    0
    cobra 2000

    switch kit i appreciate the info it turns out that the transformer was took out of the radio i had it replaced and all the lights work well nothing is dimming at this time my tech wanted to know if i wanted the new mosfet mod done to it i told him no so i left it the way it was to many people were telling me my audio was top shelf the way it was so why change a good thing!!! lol
     
    #13
  14. Switch Kit

    Switch Kit Active Member

    Joined:
    Apr 6, 2005
    Messages:
    3,517
    Likes Received:
    11
    good to hear it's working well for you the way it is now. Mosfet ? I can't really tell you anything about that ? but your radios working now and working well , might be some money later for your guy later on down the line.
     
    #14

Share This Page