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Hello,

Yesterday night I was operating FT8 and I probably heard some noise in the radio and then it was completely calm and realized fan stopped working and as temperature was rising above 40 and I switched off the radio and after 30 minutes when I switched on and connected with thetis, Seen that noise floor was much below and S meter reading was around S2/s3 usually its around S8/9 on 20 and above S9+10 or so on 40/80.

Frustrated, I switched off and went to sleep. Today morning radio was behaving normally and noise floor was up and fan wasn't working. when temperature reached around 45 I switched off and after some time i was at the operating table to find radio deaf again. This time when temperature was around 42 noise floor dropped and S meter was again S3.

Why fan Failed and why sensitivity is failing? Is it some relay issue? What to look for? What are the safe temperature levels to operate? I believe around 60.
Please help?

73
Bhanu
VU2MB

If those temperatures are in Celsius the radio is probably getting too hot and one of the internal PTC devices (temperature sensitive, self-resetting fuses) is opening.

Either the fan is broken, the fan wiring or connector, or the fan driver IC.

Thanks Scot,

Will open the case, check and update you.

73

Bhanu
VU2MB

Dear Scot WU2O

Found that this fan muffler was sucked in to the fan blades. Removed it now and Thank God fan still working.

Thank you.
73

Bhanu
VU2MB