[Amps] SB-220

R.Measures r at somis.org
Mon Dec 27 09:48:08 EST 2004


On Dec 27, 2004, at 2:33 AM, Larry Stowell wrote:

> I have a SB-220 and am wondering if it is better to turn it off when 
> its not going to be used for a couple of hours? I turn my radio's on 
> early morning and leave them on most of the day.

The good thing about leaving a SB-220 on is that it has a reasonable of 
filament-V, so not much emissive life will be wasted by wasting the 
electricity.  The bad thing about starting a SB-220 is that the inrush 
current caused by the C-filter exceeds the peak-I rating of the ON-OFF 
switch, which will eventually cause the switch to fail.  For longest 
life, install a step-start such as the one at Figure 1 on my Web site 
and oil the fan bearings every two years.
- cheers, Larry
>
> Larry K1ZW
> Durham, NC

Richard L. Measures, AG6K, 805.386.3734.  www.somis.org



More information about the Amps mailing list