Fan noise.... seems excessive on RX

K1UO Larry

The side fans on my 6700 are quite loud...louder than my I7 computer with 4 fans running and that is a foot closer to me in the shack. The 6700 is slightly over 3 ft away but the fans are quite loud for a unit just RXing. I can feel air on the palm of my hand from the rear vent holes while in RX. I just tried to see if the fans come on a higher speed by letting it transmit for about 12 minutes into my dummy load at full power (well..80 watts is all I get) and I detected no change..should I be able to tell if the speed ramps up? All I could tell is the air flow got hotter at the rear but the fans didnt change speed that I can tell. Does anyone else see a lower fan speed and less noise on RX and then hear them speed up on a prolonged TX? regards, Larry K1UO

Ken - NM9P

I have had my fan on my 6500 kick into high speed only once in the four or five weeks I have owned it. But then I don't use lots of high duty cycle modes yet.

ai6re

I don't hear any fan noise from 12" away from my 6500. I can feel the air on the side and back but it is dead quiet all the time. Don, AI6RE

K1UO Larry

Hi Ken...apparently then it is quite obvious when the fans kick in to higher speed? Maybe these are on high speed all the time.

K1UO Larry

Hi Don, thanks for the info... definately not dead quiet here....In fact the right side fan has a little bearing noise. I would expect in RX mode that I shouldnt be able to hear this amount of fan noise.

Greg

I have loud fan noise too but not constantly. There doesn't seem to be anything specific that triggers them going to high as it does it on receive, transmit when running only 5W and sometimes when running 100W. I can understand with extended keydown running them higher but I don't know why they come one in receive or running QRP. When on high they are VERY loud....loudest thing in the shack. 73 Greg

K1UO Larry

Thanks guys for the replies...Ive opened up a ticket and will sent it back for complete checkout.

Norbert

I have loud fans too constantly from the Flex 6700, independently from the receiving or transmitting Situation. And the fans are much more loud than my PCs. 73 Norbert www.dj7jc.de

Ed, K0KC

I have been operating a lot of JT65 and JT9 lately where the radio is in transmit mode for about 50 seconds and then receive mode for about 80 seconds or more depending upon whether I am in a QSO, calling CQ, or just monitoring. I do not recall hearing the high-speed (and loud) fan come on when I operate on say 15 meters, but when I switch to 80 meters, it kicks-in frequently. This is just the opposite to what I would have expected. I would assume that the transmitter would be more efficient (or at least have the same efficiency) at the lower frequency and thus radiate less heat. The VSWR is similar on both bands. Apparently there is something else in play here.

EMIL-DL8JJ

I feel the fans also to loud, or i have to sensitive airs..Hi, but definitely the Flex is the loudest RIG in my shack. Also on normal funspeed. On high speed (2 times happend to me on CW long chats) i got frightened. You can feel it clearly in quiet environment, after you switch the RIG off. cu, Eil, de DL8JJ

Tim - W4TME

The fans have two speeds; low and high. The fans operate on Low all the time to cool the PA (heat generated by the idle current) and the multiple processors in the radio. There is a temperature sensor on the PA. If the temperature exceeds 70C the fans will turn on high.