THE crip cap (in tha car) mod…..

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    • May 11, 2003 at 7:18 am #10425
      Avatar photoph2t
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      I?ve been doing this method on a few cars now and settled on this being my standard for all my cars when increasing the range. With the method outlined below I can achieve 10 meters (approx 30 feet) indoors.

      First of all, here?s my stock MS 49Mhz with a Skyline shell and crapola antenna, it will be the guinea pig for today?s little exercise?..

      Now let?s remove the shell and carefully prize the plastic pcb cover off. For all you Aussie Compact Char-G owners the pcb cover is actually glued so be extra careful. The M?Sizers don?t suffer from this, dunno about Bit Char-G.

      Next, let?s locate the nasty ‘lil bugger, you will see it outlined in red below. NOTE: This is in every car I have seen to date. Unlike the crip cap in the TX which varies at the best of times. Upon closer inspection you will notice that the solder work done on this surface mount capacitor is messy and not as clean a job as the rest of the circuit board. There are theories going around that TOMY added this cap after production due to the range being too good?..go figure?..

      Prize open the pcb from the chassis CAREFULLY, you don?t want to break anything, especially little steering wires… This is done from the side OPPOSITE to all the solder pads that say L R B F V+.

      Once you have opened the chassis up sufficiently, flip it over and secure it to your bench top using some plastic putty stuff, I?m using Bluetac in this example. You will need the pcb to be secure to give you the leverage you will need to continue?

      Now, here?s the trickiest bit of the whole procedure. Make sure you have the capacitor in the grip of some needle-nose pliers, using a soldering iron heat of the solder pads on each side of the capacitor and slowly work it loose. Be careful to not damage other components close by.

      Ahhhh, now isn?t that better? See below?. No more @#$%^ cap!

      Look how bloody small the thing is, shown here next to a steering knuckle.

      Now that the hard parts done, let?s add a new antenna. For those people paying attention I had removed it earlier. Shown below is some enameled wire (0.25mm dia) I?m using for an antenna, it works well for its purpose?..

      Remember to always TIN your wire first to allow for an easier solder job when connecting it back onto the pcb. I cannot stress this enough.

      And you?re done??

      With the cripple capacitor removed and a new antenna added, we?re ready to hit the town.

      Not without our crew though!

    • May 11, 2003 at 3:23 pm #31604
      Avatar photobarto_85
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      does the range still increase without adding the longer antenna?

    • May 11, 2003 at 3:29 pm #31605
      Avatar photoph2t
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      yes, but you get an extra 2+ meters with the antenna.

    • May 11, 2003 at 3:31 pm #31606
      Avatar photobarto_85
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      oh yeah, cool

    • May 11, 2003 at 3:32 pm #31607
      Avatar photobarto_85
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      so you get about 8 metres without changing the aerial?

    • May 11, 2003 at 3:38 pm #31608
      Avatar photoph2t
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      It’s hard to say dude. Each car reacts differently. On top of this you can tune the varible inductor on the car to really tweak the reception, giving you a possible few more meters to play with.

      EG: my 27Mhz compact char-g was 3 meters out of the box, now it’s 9 meters. My 27Mhz MS RX-7 was 2 meters outof the box and now it’s 10 meters. My 49Mhz MS Skyline was 6 meters out of the box, not it goes 11 meters+ (longest distance I have in my house)

      So you can see it varies. I’ve yet to tune the variable inductor on any of these babies yet…

      The variable inductor tuning mod is AKA QFM’s “tuning the POT” mod…

    • May 11, 2003 at 4:24 pm #31609
      Avatar photobarto_85
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      wow, thanks for the help, that sounds awesome.

    • May 11, 2003 at 10:18 pm #31581
      Avatar photomicro_Amps
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      Ph2t, tuning the vari-inductor is a must when replacing the aerial. The car may still “stutter” in certain places around the house due to the Rx being slightly off tune and receiving reflected wave signals.
      Heres how,…..
      Put a rubber band around the Tx steering button and go for a walk, do it outside.
      When the steering stutters, adjust th vari-inductance (the ‘pot’) 1/8 to 1/4 of a turn. If the steering stops working, turn it the other way.
      Keep stepping away from the Tx and adjusting at the same time until you cant get any better.
      Dont hold the car too close to your body, and dont have your body between the car and the Tx.
      And dont use a metal srewdriver.
      Once complete, you have tuned your new aerial, and should have better range and stronger signal reception when it is within range.
      Simple and effective.
      If you are going to put a longer aerial on then it is worth the time tuning the electronics to suit it.

      :)uA

    • May 12, 2003 at 1:35 am #39242
      Avatar photokevsta
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      Thanks for sharing that information and putting up the photos.

      No doubt, I will attempt that cripple cap mod soon. Just got my soldering iron back woo hoo…

      Now if only I can find my tweezers.

      🙂

    • May 12, 2003 at 4:26 am #31557
      Avatar photoph2t
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      Great advice, thanks micro. 😉

      I will tune these buggers when I get a chance and report my findings. What’s the best way to remove the wax from the inductor?

      ph2t.

    • May 12, 2003 at 11:19 am #31530
      Avatar photomicro_Amps
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      Just scrape it out with a small screwdriver. It pretty much falls out when you have a poke at it anyway. I dont bother replacing it afterwards, and havent had any problems with cars going out of tune.
      Nice set of pics too ph2t. Makes things easy to understand for everybody.
      :)uA

      P.S. Burning the midnight oil again too I see :smiley2:

    • May 12, 2003 at 1:20 pm #31506
      Avatar photoph2t
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      Thanks man, I’ll give it a go.

      Yup, the old midnight oil, seems that I have all my insight in the wee hours of the morning when I’m running low on sleep and high on caffine…

      :approve:

      ph2t.

    • May 12, 2003 at 4:26 pm #31519
      Avatar photoSurfmyStrat
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      i just did the mod!!! it didnt effect my car at all i dont know what to say, maybe i didnt do it right, but heres a question, the solder between the cap and the cb5 chip, are you supposed to get rid of it after you take out the cap??? sorry im not to good with electronic circuits and what not…:D

      you are currently at: http://www.ausmicro.com

    • May 12, 2003 at 4:49 pm #31523
      Avatar photoph2t
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      If you mean that the solder is connecting the two pads together, then no, it shouldn’t be there, you are creating a short circuit which would probably kill the car alltogether. I’m sorry surfy I don’t have a car PCB in front of me (I’m at work and I _should_ be working :shock:). I’ll have a closer look tonight.

      ph2t.

    • May 12, 2003 at 4:53 pm #31524
      Avatar photoSurfmyStrat
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      no, not the solder between the 2 pads, the solder to the CB5 chip to the side of the pad closest to the edge, refer to the pictures you used for the instructions, scroll up ^

      you are currently at: http://www.ausmicro.com

    • May 12, 2003 at 5:05 pm #31526
      Avatar photoph2t
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      Yes that solder stays there. Are you using the original antenna?

    • May 12, 2003 at 6:08 pm #31487
      Avatar photoSurfmyStrat
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      umm, yea an original antenna and i added another antenna, about half the size from one of my clones, so i guess its not a double antenna but a one & a half antenna:D

      you are currently at: http://www.ausmicro.com

    • May 12, 2003 at 6:13 pm #31475
      Avatar photoph2t
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      Ya silly bugger :smiley2:, don’t add an extra antenna on top of the other one. Add a new one all together. There will be a lot of signal loss in just combining the two, lol!:approve:

      ph2t.

    • May 12, 2003 at 6:19 pm #31466
      Avatar photoSurfmyStrat
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      yea, i was gonna, but i cant seem to find any good wire, its all either to fat or not the right kind… ill search, gotta stop by radio shack. Till then ill remove the second though. thanks for the tip:p

      you are currently at: http://www.ausmicro.com

    • May 12, 2003 at 6:46 pm #31410
      Avatar photoph2t
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      No sweats, happy to help.:smiley16:

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