"Steven Swift" wrote in message
...

I managed to get a NIB BC-454-B for pretty cheap. I decided to keep
it 100% original, so I put a Dynamotor on it and cobbled up a 28VDC
supply. Works great as a WWV monitor.

I've never run a dynamotor this long before. The question is: What is
the proper running temperature for these small dynamotors? Seems quite
hot. (Yes, I repacked the bearings).

I have another dynamotor, not for the BC-454, that says "50C continuous
operation" Is that how hot it gets or is that its expected ambient.

Steve.

I believe that 50C continuous operation means that is the maximum
temperature for continuous operation. Ambient air temperature (and even
altitude in airborn stuff) as well as circulating air make a world of
difference. Smoking the shellac is not good, and can be smelled easily if
you remove the end dust caps, and leave them off. In the golden days, I
thought something was wrong with dynamotors on surplus so-called Command
Sets if I couldn't leave the palm of my hand on the dynamotor for 10
seconds. Ouch, ouch, ouch........
Old Chief Lynn