#25 Icom IC 745 repair part 1 - tear down and review of problems

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  • Опубліковано 5 вер 2024

КОМЕНТАРІ • 47

  • @wes11bravo
    @wes11bravo Рік тому +1

    When it was working, I liked my IC-745 more than my IC-718! Anyway, your excellent series is inspiring me to get my IC-745 back on the air. I bought the Piexx board to fix my RAM issue.

  • @jaybats7865
    @jaybats7865 4 роки тому

    I think it’s awesome that you diagnose existing design flaws and then engineer, build and install corrective components to fix them. You’re amazing. Thanks for the fun

  • @mikesradiorepair
    @mikesradiorepair 8 років тому +1

    Nice to see someone else who takes care of everything at once. I have never understood people who will fix one problem at a time. It's on the bench open and already being repaired why not just take care of everything and enjoy the radio trouble free for a few more decades after that.
    Will enjoy seeing what you come up with to download and upload the program.
    Mike

    • @TheRadioShop
      @TheRadioShop  8 років тому

      +MikesRadioRepair .CBRadio I agree 100 percent. Plus the radio deserves to time spent on it. It has been a great performer for so long now so may as well do it right one time. Then it should last many more years to come.I have a few ideas for the prom programming. I do not think it will be too difficult to master. But lets remember I am no expert on programming. Now the hardware should not be much of a task.Thanks for commenting Mike.

  • @PapasDino
    @PapasDino 8 років тому +1

    Icom used to have lots of problems with their PLL's - my venerable old bought new in 1977 IC-211 2m all mode's PLL had problems with feed thru PCB via's and styrene caps. Your intro reminds me of the old time Saturday serials! Can't wait for part 2! 73 - Dino KL0S

    • @TheRadioShop
      @TheRadioShop  8 років тому

      +Dino Papas I remember that radio Dino. And all the problems it had. Icom had 4 generations of PLL and 2 or 3 generations of displays. The board had plated through holes in the early models like you mentioned.  Later Icom installed pins in the holes and this caused a few more problems. The pins were coated to bond with copper and solder, after a few years it lost the bond.Thanks for the comments my friend. We will have a bit of fun in part 2 of the series. Glad I could spark a few memories for you

  • @RestoreOldRadios
    @RestoreOldRadios 8 років тому +1

    An interesting project. I'll be following the series and hope all goes as planned. Best, Don

    • @TheRadioShop
      @TheRadioShop  8 років тому

      +RestoreOldRadios Thanks Don. I really see no problems in getting the rig up to par. Since it is basically working as is. Going to be a fun project. Thanks for stopping by. :)

  • @OrbiterElectronics
    @OrbiterElectronics 8 років тому +1

    Thanks for the look around inside your Icom here. Looking forward to the next videos in the series :)
    Cheers friend
    John

    • @TheRadioShop
      @TheRadioShop  8 років тому

      +orbiter8 (John) You are welcome and thanks my friend. This should be a fun and exciting repair as we move forward with it.

  • @TRXLab
    @TRXLab 8 років тому +2

    very nice look inside Buddy. Looking forward to your next. 73' my friend

    • @TheRadioShop
      @TheRadioShop  8 років тому +1

      +TRXBench Thank you Peter. Very fun radio to work on. Waiting for your next video also my friend :-)Thanks for dropping by.

    • @TheRadioShop
      @TheRadioShop  8 років тому +1

      +The Radio Shop Oh great! I see you already uploaded one :)

  • @mcdeadsquirrel
    @mcdeadsquirrel 3 роки тому +1

    This is just a great great video about this rig. This is my fav rig, too.

    • @TheRadioShop
      @TheRadioShop  3 роки тому

      Thanks 👍

    • @mcdeadsquirrel
      @mcdeadsquirrel 3 роки тому

      @@TheRadioShop Look for my email, B. de L.

    • @mcdeadsquirrel
      @mcdeadsquirrel 3 роки тому

      @@TheRadioShop I think I own a brick. My lituium batery is dead. And, ther eis now way on God'd Green Earth that I have the ability to remove the board and re-write the memory. I bought this rig new with the internal AC/DC [power supply and I feel really bad abaout losing this radio. Nothing lasts forever. But, this was my only and best rig that I had. I hate to part with it, but I may have to. I like your style of making these vids. You can hear your kind soul in your voice. '73 ol' friend, WA2TVN

  • @Lightning-bol
    @Lightning-bol 4 місяці тому

    Was doing cw on my ic-745 too, turned it on today and very very low recieve only on 28mhz and only FM this is my second ic-745 with the same problem I keep buying them for 500 and now they are bricks

  • @mrmetal60
    @mrmetal60 2 роки тому

    You are amazing, Thank you.

  • @Gordonseries385
    @Gordonseries385 5 років тому

    Thank you for the tips I have a ft-900 with #4 vco bad its a challenge enjoyed your work and I subscribed take care

  • @marvinmoss8127
    @marvinmoss8127 2 роки тому

    Do you know of any place where the step by step changes to fix the AGC problem in the original 745 might exist?

  • @oneflatlander
    @oneflatlander 4 роки тому

    I'm wondering what it would take to install a subprocessor and NVRAM and have it do a RAM/NVRAM compare to see if the RAM board has the correct info available and tell the main processor "everyting is OK - start the radio". If not, access and load the RAM from NVRAM. Much like the HP54503A calibration self-check.

  • @Darryl603
    @Darryl603 8 років тому

    If the radio is still plugged in, will it not still have some standby power to keep the memory intact while you change the battery? What if you changed the battery while the unit is running? Thanks for sharing

  • @andypalm7061
    @andypalm7061 6 років тому +1

    You bring up an interesting issue regarding the 3 volt back-up battery.
    i was wondering if the same program loss issue is possible on the IC-R7000?
    I'm just completing a re-cap,and before I put it together,maybe i should change it out. It reads 2.74V now. Nice job on the vids,I find this project very interesting.

    • @TheRadioShop
      @TheRadioShop  6 років тому +1

      Hi Andy, The R7000 does not have the ROM problem as the R7100, IC-745, IC-751. So no worries there. I would change the battery though. The biggest problem in this unit is solder joints and capacitors.

    • @andypalm7061
      @andypalm7061 6 років тому

      thanks so much for the clarification Sir,i feel better knowing I have some time to re-fit this old battery mount with a proper battery holder,so it can be swapped-out without tools in the future. I really enjoy the diagnostic process in your vids. 73

  • @supyrow
    @supyrow 8 років тому +1

    two AA batterys, connect em to the ram board and switch out the battery ( dont use a power supply to do it! ) Good Luck! I know you can do it! Be Well EDIT i didnt know you had a link to it HAHA

    • @TheRadioShop
      @TheRadioShop  8 років тому +1

      +su pyrow I try to provide as much information as possible at times. Thanks for the info :)

  • @revbikerbigd8664
    @revbikerbigd8664 Рік тому

    My ic740 no transmit power at all, receives great. Any ideas ???

  • @maninthevan53
    @maninthevan53 8 років тому +1

    This radio reminds me of the Yaesu FT 101 to me a little difficult to repair

    • @TheRadioShop
      @TheRadioShop  8 років тому

      +danny blackhorse Hi danny. I find the 745 very easy to work on. It is laid out in a manner where you can get to the boards without having to remove a lot of other stuff. Have a peek inside the Kenwood FT-930 and 940's. They are night mares lol. Thanks for your comment and for dropping by.

  • @CliffFoxKU4GW
    @CliffFoxKU4GW 8 років тому +1

    I ran one of these my first 9 years as a ham and the design flaw I wound up having to get repaired was the 4 trimmer capacitors in the PLL VCO unit that control the lock voltage on the phase locked loop. Mine had the pancake power supply which I think accelerated the trimmer caps to loosen up over time from the board being repeatedly heated and cooled every time the power supply was switched on and off. You would think that the design engineers at Icom would have known that heat rises and put the power supply in the top of the radio instead of in the bottom under all the circuit boards! I also wound up having to get the RAM module replaced as well. When the battery went dead the frequency counter went to all zeros and had no receive or transit. Clif Holland KA5IPF at www.avvid.com repaired mine for around $225 and when I got it back it worked and looked like a new radio! I loved the radio and it had every bit as good a receiver as my next radio which was a Kenwood TS-570D. I sold my IC-745 at the Charlotte Hamfest for $400 to a ham from Asheville, NC. Sold my TS-570D to a ham in Ohio and have been running a Yaesu FT-1000MP Mark V ever since. Thanks for the great video and I look forward to the next one! Very 73 de KU4GW Cliff!

    • @TheRadioShop
      @TheRadioShop  8 років тому

      +Cliff Fox (KU4GW) Cliff, very insightful reply my friend. Sounds like you went through all the flaws with your 745. Cliff Holland knows his stuff on these old rigs. Not sure if he still works on them now. Since parts are starting to become unobtainable. Your comment on the power supply as I mention very briefly in the video is dead on! Guess if you are going to cook something you put the fire under the food LOL. My suggestion on the supply is remove it and run external. However another alternative is to remove supply, make the DC cord longer and run it externally. But some cleaning up of the internal filters are needed to reduce the "birdies" created by the supply. Also love the Yaesu FT-1000MP. Great rig. Always wanted one for myself. Thanks for coming by and sharing your story.73 Buddy

    • @CliffFoxKU4GW
      @CliffFoxKU4GW 8 років тому +1

      The Radio Shop Hey Buddy! I threw the pancake supply in the garbage after the filter caps needed replacing due to hum and never installed it back in the IC-745 after Cliff Holland sent it back. A friend in Lenoir, NC sold me a Icom PS-55 power supply for only $55.00. I still have that power supply and it still works great after 10 years of use powering my VHF equipment. Very 73 de KU4GW Cliff!

    • @TheRadioShop
      @TheRadioShop  8 років тому

      +Cliff Fox (KU4GW) Good deal on the PS-55 Cliff. That is a rock solid supply. You did the right thing by ditching the pancake! BTW, visited your QRZ page. Very impressive! Have not been in your part of the state in a long time. May have to get over that way one day again. Any snow there? had a bit up in Raleigh today but nothing here.. 73 de kc4umo

    • @CliffFoxKU4GW
      @CliffFoxKU4GW 8 років тому +1

      The Radio Shop I got enough snow this morning to coat the evergreen trees really beautiful and cover the yard, but the temperature stayed warm enough it never stuck on the dirt road at all and after 11 AM the sun came out and it was all gone in a matter of minutes. That's the kind of snowstorm I like to see because I live up on the NE slope of Barretts Mountain west of Taylorsville 1 mile off of the state maintained road so when it snows a lot I can't get up the mountain to get back to the house! Going down the mountain is no problem. Just looked at your QRZ and we're the same age. I was born May 10, 1961. Give me a call sometime. I hang out on 3.895 a lot in the evenings.Great bunch of hams on that frequency and we'll talk to anyone, unlike a lot of the 75 meter groups who have their own little groups that won't talk to anyone who hasn't been in their group for years. The 3895 group is just the opposite. Very 73 de KU4GW

  • @frostking57
    @frostking57 7 років тому +2

    hey i fount what was wrong....lose board inside on the icom 730.

    • @TheRadioShop
      @TheRadioShop  7 років тому

      Great job Gary. Glad you got it going

  • @frostking57
    @frostking57 7 років тому +1

    hey one of my friend has a icom 730 has no recive on it....unless he puts a preamp on it....any i-deals.....could this be the relay dirt?

    • @TheRadioShop
      @TheRadioShop  7 років тому

      Hi Gary. The 730 is an oldie. On the RF board resolder J2 and J3 as the solder connections crack over time. Make sure the internal preamp is working. Need a scope to test. Relay RL1 will fail over time and will cause low receive issues. Hope this helps.

  • @ffp1974
    @ffp1974 7 років тому +1

    i have a 740 and need to replace the meter display bulbs. do I take the front cover off or the top cover?

    • @TheRadioShop
      @TheRadioShop  7 років тому

      Remove top and bottom cover. You can mow remove the screws to the front panel and tilt it out for access to the lamps.

    • @ffp1974
      @ffp1974 7 років тому

      Are there two lamps?

  • @lougiovannetti3612
    @lougiovannetti3612 4 роки тому

    I need my Icom 745 repaired. I think it is a trim capacitor problem I am looking for anyone who repairs these radios?

  • @jackjohnson9989
    @jackjohnson9989 7 років тому +1

    Do you take work from abroad?

    • @TheRadioShop
      @TheRadioShop  7 років тому

      Hi Jack. I do when I can. But I work a full time job so I stay pretty busy. Click the show more tab under the video for my contact information.

  • @crappieboss
    @crappieboss 2 роки тому

    I wish you were my neibor. Could learn a lot from you and gain a great friend.
    KF0IIJ chris