Re: LV2000 demands

On Thu, 19 Nov 1998, Gregg Woodcock wrote:

> These transistors can be made pretty well invincible by simply adding large
> TO-3 heat sinks on them. I have been running a Tempest with this and the
> LV2000 on it for almost 4 years 24/7 and I am running it FULL SCREEN (no
> reduced height/width). BGMicro sells them for a few cents each. 3 of them
> need to be "clipped" because 1 is entirely under the deflection board and 2
> others are partially under it. The alternative to clipping is putting the
> transistors on the OTHER side of the chassis so that the heat sinks are away
> from the PCBs (which is an OK idea since they get better air flow and are
> greatly insulated from the heat-generating boards).
>

        I was thinking about this, and this message might be high
on the "duh" factor, but....

        Doesn't the monitor chassis itself act as a huge heatsink?
Adding a TO-3 heatsink wouldn't seem to increase the heat transfer
from the transistors, by much, because they're adding only a small
amount of surface area, compared to the metal chassis of the
monitor, itself.

        Also, weren't we discussing way back that it might actually
be inductive kick from the yoke that takes these out, rather than
overheating? As I recall, the 2N3716/2N3792 are rated very nicely
current-wise. Or am I thinking of the G-08? Looking back, now, I
would think some nice inductive voltage spikes can and do happen
in either scenario (k61xx or G-08) and neither has those output
transistors diode-protected.

Joe
Received on Mon Nov 23 08:52:47 1998