Icom: Icom IC-765 Not Turning On

[shortwaver]

I received this nice radio from an older ham. We inspected it at his house, removing it from its box and bag (it had a strong "electrical burned" smell when opening the box) and tested it on receive for about an hour before boxing it back up to take it home.

When getting it home I removed the cover looking for any obvious issues, and found none. I then attached a Par End Fed antenna and some headphones to see how well receive would work on the par end fed. After powering it on, I didn't hear any traffic, and the meter wasn't moving at all while tuning around; all lights were working. After about 10-15 seconds, I realized that the "Transmit/Receive" switch just below the Power button was set to Transmit, and the red transmit led was lit. I quickly switched it to Receive and started hearing traffic. I moved to the 40 meter band and switched to ssb and was listening to traffic. Just then, the radio started making a vibration; I had headphones on and could barely hear it but could feel it in the tuning knob. The radio then shut itself off, and won't turn back on.

I've checked the fuse, and it's fine.

I'm not sure if having it run in Transmit mode for 15 seconds damaged it, though I did have an antenna on it, but I don't know what the swr is presently (probably not great).

Anyone have any ideas on what could be wrong, I really would like to get it working.

73
Marc W1MCX

 

[n9mxq]

Depending on how long it was stored, I'd start looking at capacitors

 

[shortwaver]

I found a very good resource online from VE3HUR called "Icom IC-765 Notes" at this link http://www.ab4oj.com/dl/765_108.pdf

Item 4.1 describes a common issue regarding "Antenna Tuner Hunts or Chatters". This sounds like it may be similar to what I was hearing.

 

[n9mxq]

That may well be, but it most likely doesn't have anything to do with it not turning on.

 

[shortwaver]

That may well be, but it most likely doesn't have anything to do with it not turning on.

I agree, though it may have been the sound I heard. There can't be too many physical noises that it can make.

 

[n9mxq]

Just for kicks, have you tried a CPU reset? (IC-765 - Hold [M-WRITE] button and turn the radio on. )

 

[shortwaver]

Just for kicks, have you tried a CPU reset? (IC-765 - Hold [M-WRITE] button and turn the radio on. )

I have not, but I'll try that when I get home.

Thanks

 

[n9mxq]

Don't think it'll work, but it certainly can't hurt to try...

 

[WA0CBW]

One of the first trouble shooting steps is to check the voltages. This includes any voltage regulators and capacitors in the power supply section.
BB

 

[shortwaver]

Thanks for the helpful pointers. I brought it to a friend that took a look at it and got it working - mostly. The problem was with a relay in the auto antenna tuner section. He suggested to just disable it, as the cost of repairing it would approach the radio's worth. He suggested using an external tuner, or a resonant antenna.

73