[Amps] LK 550-ZC

[Rob Atkinson]

If you have 3 3-500s to cool and you operate any serious duty cycle at
what the amp is capable of you probably need the high speed and accept
the noise problem.
hams obsess about fan noise far too much if you ask me.


73

Rob
K5UJ

On Sat, Mar 17, 2012 at 12:16 AM, Dick Green WC1M <wc1m73 at gmail.com> wrote:
> Guess I have a real late one: it has the fan speed temperature sensor. The
> stock fan speed is too slow in low-speed mode, so the fan cycles low-high
> constantly. And it's like a freight train at high-speed. I increased the RPM
> at low-speed so it goes to high speed much less often. That didn't raise the
> noise level very much. I also decreased the RPM in high-speed mode, which
> reduced the sound considerably, but didn't appreciably affect the cool-down
> time to low speed. I used a temperature probe to make sure the tube
> temperatures stayed well within spec.
>