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PEN Heat sink replacement

What a classy company. My kit arrived on Friday and it took longer to remove the 14 Torx screws than the update took. I followed the instructions to the letter (at least I thought I did) and after I installed the 14 Torx screws I was ready to put the installation manual in my FLEX hardware notebook. It was then I noted the vertical direction of the fins on the new heat sink in the manual. FLEX did supply a Torx driver (nice touch) but I decided to go and get a set of Torx drivers at Home Depot. They had two one at just under $6 and one just under $10. I opted to spend 10 bucks since it came with a variety of drivers and bits in a nice plastic case. The swivel head made it easy peasy. PLEASE be careful to be sure the heat sink fins are oriented vertical, I am not sure what the issue would be if they were not. Fortunately when I re-opened the cabinet to check that I had not **** up the fins were the way they should be, lucky me, good to check. Perhaps Tim or Neal can advise if they were not. Anyway done...Thanks FLEX
Neil   N4FN


  • Gary L. RobinsonGary L. Robinson Member ✭✭
    edited June 2018
    I got my kit on Saturday and , as you said, it took longer to take the screws out than to do the heat sink fix. All went well and the radio is back on the air and running well. 

    Thanks Flex!

    ---Gary WB8ROL
  • Ron W4RDMRon W4RDM Member
    edited June 11
    Installed my heat sink kit tonight on my 6400. The original heat sink had dropped to the bottom of the board.

    The radio had been on 24/7 until the PEN announcement since I received it on Feb 7.  


    I moved the original heat sink back to the chip and installed the new heat sink on the rear of
    the board. Added the orange wire tie 


    Torx screws were not a problem with my battery powered torx driver. Removed and installed the screws in less than a minute. Radio is back on the air.


    Ron W4RDM
  • WayneWayne Member ✭✭
    edited July 2018
    The heatsink fins are vertical so the airflow coming threw from the fan will be unimpede and flow across the fins of the heatsink since hot air rises.
  • Neil   N4FNNeil N4FN Member
    edited July 2019
    Did you leave both heat sinks installed and not remove the original one?
  • Ron W4RDMRon W4RDM Member
    edited June 2018
     I have both heatsinks installed now. The original had came off and was stuck to the bottom of the board at the connector.

  • Neil   N4FNNeil N4FN Member
    edited July 2019
    Why have both??
  • Alan CAlan C Member ✭✭
    edited June 2019
     I couldn't get my old heatsink off - so I installed the new one, and zip tied - just like the picture.
    Also, I wondered why FRS included a couple of case screws - well I found out why. The first **** I took out was dropped and went into deep space. Thank you FRS for thinking of that!
  • Mark WS7MMark WS7M Member ✭✭
    edited June 2018

    I did the same thing.  Both of my old heat sinks were on rock solid so I just left them on, installed the new ones then zip tyed around both.
  • Steve K9ZWSteve K9ZW Member ✭✭✭
    edited June 2018
    Under ten minutes to do the heat sinks on a 6600M. Included the time from disconnecting everything to reconnecting it back up. https://k9zw.wordpress.com/2018/06/03/flexradio-systems-flex-6600-heat-sink-replacement/ A couple quick confirming QSOs and all is well! 73 Steve K9ZW
  • WD4EGFWD4EGF Member
    edited June 2018
    It was nice to see the noise floor drop a couple db on my 432 xvtr after the installation. My heat sinks had fallen off at some point, and the new ones seemed to make the difference. Thanks Flex for addressing this... better noise perf is great, no more metal objects floating in the cabinet, priceless, hi. 73, Don WD4EGF
  • Rich McCabeRich McCabe Member ✭✭
    edited June 2018
    Was an easy install for me too.  One of two heatsinks were laying on the bottom.

  • edited July 2018
    Anyone know What size are the size of the Torx Screws T# ?? are for the Flex6600
    73 Mike
  • Rick  WN2CRick WN2C Member
    edited July 2018
    Well Mike, if you have ordered the kit it will come with the proper torx wrench to do the install.
  • David Decoons, wo2xDavid Decoons, wo2x Member ✭✭✭
    edited July 2018
    T8. I used the T8 bit and my magnetic screwdriver kit. It was easier than using the T8 L wrench they send. The L will work though. Dave wo2x

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