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    #16
    Originally posted by gadget73 View Post
    vacuum desoldering guns are your friend. Use one and you'll never use the wick again.
    QFT!

    I really wish I had one. I need to put one on my wish list.

    Only two things are infinite, the universe and human stupidity, and I'm not sure about the former. -- Albert Einstein
    rides: 93 Crown Vic LX (The Red Velvet Cake), 2000 Crown Vic base model (Sandy), 2003 Expedition (the vacation beast)
    Originally posted by gadget73
    ... and it should all work like magic and unicorns and stuff.
    Originally posted by dmccaig
    Overhead, some poor bastards are flying in airplanes.

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      #17
      Man, this a good thread for gear ideas! Vacuum desoldering gun. "I've never seen anything like that before in my life!" - ElderlyIron.

      Gadget, you've told me before what STK modules I need to buy to replace the dead ones and yet I never buy them. Mostly because I don't have a car that needs some, well, Ashley's Mark VII could use them but she putters on with her aftermarket amp..
      1985 LTD Crown Victoria - SOLD
      1988 Town Car Signature - Current Party Barge

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        #18
        Originally posted by gadget73 View Post
        Honestly with the old JBL factory amps I have not had cap problems. Every single one has been the STK amp module. Frankly I'm amazed that I haven't had cap issues with them. Its near 30 year old gear with a switch mode power supply inside.

        Stuff that doesn't use those stupid amp chips is more likely to be caps or solder joint problems though. Depends on construction. The JBL amps were surprisingly well built, Nichicon caps, lots of stand-offs to support the boards, well flowed joints. I've seen other stuff that was pure garbage inside though. The ones with almost no board support that let the leads on the output devices flex and crack are awesome. A lot of them have input jacks crack loose for the same reason, poor mechanical support and it just breaks loose. Cars are a tough environment and if you don't have good physical construction the rest of it almost doesn't matter.


        vacuum desoldering guns are your friend. Use one and you'll never use the wick again.
        Plus one a good quality desoldering station is the way to go especially if you do a lot of circuit level repairs, it may be over kill and cost prohibitive for a diyer to " try " and fix one amp which is why I did not mention it.

        Back in the day when my brother and i were cranking out Amp repairs and upgrades I only found one AMP that had worthy hand done solder connections yet since i am a old fart now I cannot remember the name, The PCB was American flag theamed, it was so cool and detailed and well made yet not one owner - user probably ever saw this quaility work since it was covered up by none see through covers.

        My brother taught me to add new solder to the connectors I wanted to remove then let it cool down before attempting to desolder it with wick or a desoldering gun. Is this what you do as well?

        It seems doing it this way would net a more complete removal of the old solder

        As far as Caps going bad I cannot speak for JBL or any brand AMP which is better than others for Caps staying good. I know my on board cap checker found thousands of bad caps over the years. we made it a habit to check each and every cap if we found a suspect cap with the meter normally it was obviously bad with signs of electrolitic that leaked out if it was not obviously bad but suspect we would unsolder one leg and check it with a different machine.

        In the end I hated assembly line solder bath connections yet this type of manufacturing made my brother and I a lot of money over the years.

        The part I hated because my brother was a electronic repair man he learned to only do what the customer aggreed to pay for, which meant he had no problem just fixing the few solder connections and parts that failed and leaving the rest of the Amp prone to fail again becuse he knew they would be back yet for a different problem later down the road.

        I always wanted to make sure each and every connection was perfect and every part was checked before shipping the Amp, TV VCR etc out. yet this meant I could never compete with him in a production line enviroment.

        Two reason that I could not compete with him first off he knew how to read a schamatic I cannot even spell it LOL let alone know enough trace a problem down to the circuit then the part.
        I allways had to do the shotgun method mainly from lack of experiance and training and tools.
        2007 Ford Crown Victoria LX Sport

        Comment


          #19
          Originally posted by DerekTheGreat View Post
          Man, this a good thread for gear ideas! Vacuum desoldering gun. "I've never seen anything like that before in my life!" - ElderlyIron.

          Gadget, you've told me before what STK modules I need to buy to replace the dead ones and yet I never buy them. Mostly because I don't have a car that needs some, well, Ashley's Mark VII could use them but she putters on with her aftermarket amp..
          STK2240 is the original, STK2250 is a direct sub. Beware the counterfeit ones though, they are not known to work reliably. The genuine article are getting hard to find anymore for a not-stupid price.


          I usually have some fresh solder on hand to add a bit before pulling it off if needed. If the existing connections are clean and the tip is tinned it usually works out oK but if it doesn't melt properly adding a bit of fresh lead will usually make it work.

          I'm sure if I really went through those JBL amps I'd find some caps in less than perfect condition but none of them have been bad enough to actually cause any trouble. I don't think JBL actually built them either honestly, it just has their name on it. They're sort of an odd amp, custom EQ curve dialed to match the car and speakers, different levels front to back, and its different per-application too. Towncar amps are not the same as Mark VII amps, though they will basically sub for each other. The levels and such don't match up precisely. I have one of each here, never sat them side by side to see what is different though.
          86 Lincoln Town Car (Galactica).
          5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

          91 Lincoln Mark VII LSC grandpa spec white and cranberry

          1984 Lincoln Continental TurboDiesel - rolls coal

          Originally posted by phayzer5
          I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

          Comment


            #20
            How does a layman go about spotting fakes from the genuine article?
            1985 LTD Crown Victoria - SOLD
            1988 Town Car Signature - Current Party Barge

            Comment


              #21
              Other than knowing its on ebay for way cheaper than anywhere else with a ship-from address of Taiwan, China, or Hong Kong, I don't rightly know. I'm sure there are experts that can tell you what specifically to look for besides that. Sometimes you can tell just because the printing or something else looks off when compared to a known original part. Different font on the print, stuff like that. Kinda need to have a known original for reference though.
              86 Lincoln Town Car (Galactica).
              5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

              91 Lincoln Mark VII LSC grandpa spec white and cranberry

              1984 Lincoln Continental TurboDiesel - rolls coal

              Originally posted by phayzer5
              I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

              Comment


                #22
                Oh yeah, like Chinglish right? I'll keep that in mind. I finally cleaned up my basement work area so all I need now is a good chair and I can make repairs happen.
                1985 LTD Crown Victoria - SOLD
                1988 Town Car Signature - Current Party Barge

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