[Kenwood] TS-940S Cooling Fan Problem

[Walt Breining]

Bill:
I believe that your fan is OK.

I cannot find a schematic on the 940s except in a manual that will take me 3
hours to download on my 33.6 system from mods DK.  I may try to download it
somewhere else next week.

I would guess that  the fan is switched on with some sort of solid state
switching or run by a 12 V regulator and the switching or regulating
transistor is bad. This is causing a condition where there is series
resistance in series with the fan voltage.  With no fan, you show good
voltage, but as soon as a load is put on it, the drop across the resistance
is almost the entire supply voltage.

When I get a diagram, I can be more specific, but I am betting that the fan
is OK.


Vy 73, Walt N9WB

> I was using a DC supply (no wart)....it runs & starts fine if the voltage
> gets above the 1.5vdc or so area...Bill

> > What happens if you hook it to a good 12v DC supply, not a wall wart?
> > Walt N9WB

> >> Walt, its a 12 vdc motor...Bill
> >> > How many volts is the fan made for? I am wondering if it is driven by
a
> >> > transistor that is bad
Walt N9WB