Icom: 706 need help with ID missing components

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snoack321

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Bought a used icom 706, hooked it up to pc and receiving ft8 no issues!

Checked transmit with MFJ-945 and nothing. Used Rig with just mic … nothing.

Opened up top and oh boy someone had hacked main board BF688F and I see missing transistors, a hacked switching diode that was not soldered properly and when I turned over unit a SMD fixed inductor fell out (1R2J).

My question to the group. Can some kind soul send me a pic of what components should be in these areas (see pics) so I have a chance to fix properly?

Thanks!!
 

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snoack321

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Found board but can’t read component types. What makes this board unique VS other boards is the 50w/100w switch.
 

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AK9R

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I think that the service manual would tell you what you need to know. The service manual will provide a schematic, a parts list, and a pictorial board layout.

Some of the "missing" transistors you show may not be missing. Those pads don't appear to have ever had a device soldered to them. I assume that Icom uses the same printed circuit board for different versions of the radio and different versions may not use all the same components.
 

snoack321

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Thx for replying AK9R. You are exactly right in that solder pads that look perfect probably indicate components that are not needed and a service manual is crucial since each model has very different PCB design.

I ordered a service manual for 706, fixed some grounding tabs that broke off, removed components that were rattling loose in the case (shocked face), took a screw driver and exercised particular pots that are known to be issue and soldered in replacement High speed switching diodes that were missing.

And, it now works!!! I tried both 50w and 100w switch and both work!!
415CBB78-80F5-4549-B163-3E0FAAFCBE70.jpeg
 

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