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Chuck Harris · September 28th 06, 06:16 AM posted to rec.radio.amateur.boatanchors

Steven Swift wrote:
(Steven Swift) writes:

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.

TIA.

I have gotten a couple of emails asking: "have you checked all the
loads, capacitors, etc.?" Yes. The loads are perfect. I am thinking
these beasts must just be hot runners.

They are. Most that are intended to drive a transmitter have an intermittent
duty rating. They are turned on when you key the transmitter, and turned
off when you release.

The units for receivers usually run on the warm side of cozy.

-Chuck Harris