max temp the radio have

James Kennedy-WU5E

What is the max temp the radio can safely operate?  this evening while on JT9 the temp of the radio was 51.9C , The fan ramped up and radio cool down pretty fast after the last QSO.

John n0snx

Hopefully this will answer your question James.... Here is the response to an earlier post...

Eric - KE5DTO, Official Rep

• 283 Posts
• 74 Reply Likes

Official Response

We definitely do a keydown test on all of our radios before we begin shipping.  I don't have the detailed data in front of me for the FLEX-6300, but I can assure you the answer is 100W.  Typical behavior on these tests in our lab is the radio will asymptotically approach an equilibrium where the heatsink's ability to cool equals the heat dissipation of the transistors.  This point is well under 90° C in our lab environment and I know we have done multi-hour tests to prove this on all of the FLEX-6000 series (in at least one case, we ran them overnight).

Obviously the ambient temperature and airflow factor into this equation, so we will do shorter tests where we constrict airflow.  Rest assured that the transistors (and surrounding design) in these radios are very rugged.

Steve-N5AC

The radio will warn you when it is within 5C of the operating cutoff and give you an opportunity to fix any airflow/temp problems.  The radio will self-protect when it gets to its temperature limit by shutting down.  You will have a warning in SmartSDR on the PC when/if this happens.

Peter K1PGV

High fan speed kicks in at 70c. The radio shuts down at 90c... Both temps measured at the heat sink, which is somewhat cooler than the transistor itself, and the transistor is rated for a considerably higher temp. So, at 50c I don't think you have anything to worry about.