service manual icom-251E and wire diagram mutek board

Started by nofake, June 04, 2020, 02:25:51 pm

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nofake

Hello,

I am looking for the service manual for the Icom ic251E and the wire diagram for the mutek frontend board.
I had a problem with the mutek board and took it out without making pictures or schematic of the wires, and now i have nothing on the recieving end.
Can anyone help me with this problem.

73
ON3TVA

Sparks

Quote from: nofake on June 04, 2020, 02:25:51 pmI am looking for the service manual for the Icom ic251E and the wire diagram for the mutek frontend board.

1. Free download here (PDF): https://www.manualslib.com/products/Icom-Ic-251e-3963801.html

2. Check pages 12-19 in this PDF about "ICOM IC-251E + MUTEK BOARD":
https://worldradiohistory.com/UK/Amateur-Radio/Amateur-Radio-1983-07.pdf

I didn't succeed in finding the Mutek circuit diagram for you. I found these phrases at more than one site, probably what you didn't do?:

Quote from: undefined(1) FRONT PANEL

  • Remove four retaining screws and top cover.
  • Remove four retaining screws and bottom cover, disconnecting the speaker.
  • If you have a Mutek front end board fitted remove it now. MAKE NOTE OF THE CONNECTIONS TO IT! ***WRITE IT DOWN***
  • Remove the four front panel frame screws
  • disconnect the wiriing harness and remove the front panel. NOTE WHERE ALL THE PLUGS GO! ***WRITE IT DOWN***
  • Locate the orange wire linking the mode switch and the board behind the power control potentiometer.
  • Desolder it from it's present position on the mode switch and move it to the common side of the switch. That completes the front panel mod.
This example from: http://www.pa7es.nl/All_ICOM_mods.pdf

Put this exact search phrase (with quotation marks) into Google:
"If you have a Mutek front end board fitted remove it now"
Check the hits, even the picture hits, maybe something there will yield what you need. Good luck!

gil

Hello,

Mine is starting to act up a bit, with a few-second delay befopre starting... Probably a capacitor going bad...

Gil.