R8600 Strange Issue Noted

[MStep]

My 8600 is about 8 months old. Had been working fine, but while monitoring heard what almost sounded like a rippling sound out of the external speaker. This was while monitoring in NFM mode with the 15 KHz. Same thing coming out of the internal speaker with the external unplugged. The sound is just "not right" any longer on my 8600. Prior to this sudden incident, when switching to the 50 KHz filter on a NFM signal, the sound would be nosier but had fidelity. Now the sound is very hollow and tinny in 50 khz mode.

So something definitely happened to this radio. This occurred suddenly during normal operation. Tried powering off and on, partial rest, full reset, reinstall firmware--- all to no available. NB and NR modes are normal.

Anyone else have an experience similar to this ? Thank you in advance for your input.

 

[AOR-262]

@MStep

A video showing us exactly what you're experiencing would be great.

 

[MStep]

@MStep

A video showing us exactly what you're experiencing would be great.

If I could do an A/B comparison that might be helpful. But the radio is permanently in "B" (as in Bad) mode--- just seeing if anyone else here has experienced anything similar. In the meantime, if I can get it together with a friend's 8600, I'll try to do a video.

 

[prcguy]

Does it sound like an audio amp is damaged and distorted or like its receiving in the wrong BW or mode or ??

 

[MStep]

Does it sound like an audio amp is damaged and distorted or like its receiving in the wrong BW or mode or ??

Yes, that would be one way to describe it. With the "normal" bandwidths I employ, the radio is operational and intelligible. Yet after making that "rippling" sound, something with the audio and/or filtering is just "not right". I'm gong to have to do a comparison with a friend's 8600 when I can.

 

[mrkelso]

Resetting; Dpartial Reset; Dall Reset - Icom IC-R8600 Instruction Manual [Page 79]

Have you tried a reset?

 

[MStep]

Resetting; Dpartial Reset; Dall Reset - Icom IC-R8600 Instruction Manual [Page 79]

Have you tried a reset?

Yes, as I mentioned in my original post, I did a partial reset, then a full reset and also reinstalled the firmware. No luck with any of that. The very first symptom was the rippling noise I heard from the external speaker (same one I have been using for the part 8 months). Almost sounded like the speaker had gone bad--- like it was ripped and vibrating. But the poor audio continued with the internal speaker as well.

This is somewhat difficult to describe, although a few posts ago, prcguy pretty much hit it when he asked, "Does it sound like an audio amp is damaged and distorted or like its receiving in the wrong BW or mode or ?? "

I think the only way to understand it would be if I find someone here who had a similar experience. Once I get my hands on a second 8600 and can do the right kind of A/B comparisons and post that here, the issue might be clearer. Having used the radio for the past 8 months, something suddenly does not sound right.

I do appreciate your input, as well as others who have made suggestions here.

 

[MStep]

Does it sound like an audio amp is damaged and distorted or like its receiving in the wrong BW or mode or ??

Some clarification: Yes, def like an audio amp may have gotten screwed up. Not like wrong BW or mode. Thanks again for your input.

 

[swman]

You may wish to give firmware version 1.32 a try (a step back from the latest 1.33). I have noticed that 1.33 has some audio distortion issues in AM mode (MW/SW listening). Going back to 1.32 cleared that up.

 

[MStep]

You may wish to give firmware version 1.32 a try (a step back from the latest 1.33). I have noticed that 1.33 has some audio distortion issues in AM mode (MW/SW listening). Going back to 1.32 cleared that up.

Thanks for the advice--- def worth a try, although this was a "sudden onset" event---- 1.33 had been working fine.

 

[swman]

As it always goes with firmware the latest is not always the best. I know I had to revert back to v1805A with the AOR AR-DV1 as with the latest v1812 it was doing weird things intermittently in the VFO mode (receiver drop outs with A-B switching and strange sensitivity). AOR has been advised.

 

[w4amp]

Did you try it with a different power supply?

 

[majoco]

Try taking a signal from the AF out jack (not the speaker jack) on the rear panel and feeding that through an external amplifier and speaker to see what that sounds like. If it's good, then you audio amp/speaker in the 8600 is supspect - if it still sounds bad..... Why are you using a bandwidth that is not appropriate for the signal you are receiving? What does it sound like on a VHF FM broadcast sation with the WFM bandwidth set?

There was a design fault with the Icom R7000 on FM that only seemed to occur in very dry locations or climates - mine did it. What happened was an audio amplifier IC had no DC return to ground on it's positive input - the input sources current but it has nowhere to go - the voltage rises forcing the output voltage higher and higher until it meets the maximum voltage out with lots of distortion. A high value resistor to ground from the positive input solved the problem.