[Amps] MFJ products

[Jim Garland]

I believe Manfred is exactly right. Linear power supplies tend to be 
less trouble-prone than switchers, but when they do fail, their failure 
mode can dump a significant overvoltage on their load. Fortunately, an 
inexpensive crowbar overvoltage circuit solves that problem. For me, I 
always prefer to use linear power supplies because they last longer and 
never  cause RFI problems, which switchers are prone to. On the other 
hand, the switchers are lighter and significantly more efficient than 
their linear counterparts, and cheaper too, so ultimately the decision 
which to use comes down to personal preference.

73,

Jim W8ZR


On 12/7/2017 7:08 AM, Randall, Randy wrote:
> The bottom line is that switching power supplies are far less likely to expose a radio to overvoltage, although it's likely that their overall failure rate is higher than that of linear power supplies, owing to their higher complexity. Where there are more parts, there is more that can go wrong.
>
> A high power linear power supply should always be fitted with a crowbar-type overvoltage protection. A switching supply can also be fitted with one, but it's less necessary.