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Technical Topics => The RF Workbench => Topic started by: Matt285 on July 05, 2019, 1257 UTC

Title: Icom 718 problems
Post by: Matt285 on July 05, 2019, 1257 UTC

Yesterday I noticed my radio seemed to be dead on receive. Especially being that it was July 4th and a lot of people were off work. It also seemed to have Shortwave splatter across all of 40 meters as well as other bands. My attenuator is working in reverse. I have to turn it 'on' to hear anything. I keep having birdies popping up all over also. I did make a contact on 20m USB last night. I'm worried it may have taken in some voltage some how. Any thoughts?

Title: Re: Icom 718 problems
Post by: Josh on July 05, 2019, 1636 UTC

Sounds to me like you may have diode rectification of a strong local signal going on in your antennae system. Or perhaps the noise blanker is set a bit too high?

Title: Re: Icom 718 problems
Post by: Matt285 on July 05, 2019, 1646 UTC

I've never had an issue with local transmitters. I will double check the noise blanker setting. I'm hoping its something simple. It's been a good rig so far

Title: Re: Icom 718 problems
Post by: Josh on July 05, 2019, 1648 UTC

Also check preamp, set it to off.

Title: Re: Icom 718 problems
Post by: Matt285 on March 09, 2020, 1507 UTC

Finally sent the Icom off for repair a week ago. The following repairs were made by the tech.

RF Pre-amps blown , replaced
RF ATTN Diodes Blown , Replaced
RF/IF resistors , there were 3 of them cracked.
Labor 1.8 hours plus parts

Title: Re: Icom 718 problems
Post by: redhat on March 09, 2020, 1653 UTC

Sounds like either a lightning hit, or the transmit/receive switching failed to operate correctly.

+-RH

Title: Re: Icom 718 problems
Post by: Josh on March 09, 2020, 2055 UTC

Have a gas discharge arrestor inline?

Title: Re: Icom 718 problems
Post by: nickcarr3151 on March 09, 2020, 2143 UTC

Quote from: redhat on March 09, 2020, 1653 UTC

Sounds like either a lightning hit, or the transmit/receive switching failed to operate correctly.

...or tx'ing w/o an antenna would do the trick!