#995 Jul 15, 2000
Ok, I did some tests today with the 600 GOTO and here is what I
The Kendrick Dew Heater (12" version), when added to the circuit
that the mount is on, draws between 0 and a little over 2 amps, in
pulses. I speculate (but did not test) that when the dew heater loads
up, the voltage on the circuit drops to below 12 (I have measured this
before and reported it here). This can cause the AP600 Keypad to
What I did was to put a regulated 12V power supply and a 120V AC
inverter on the circuit, to insure exactly 12V regardless of the load
from the dew heater. I tested the current on the dc-ac side of the
curcuit and the dc-dc side of the circuit. Together the dew heater and
mount draw between .5 A and 3.5 A on the dc-dc side, and between
1 A and 7 A on the dc-ac side.
The good news is that the arrangement works perfectly and delivers
exactly the voltage I need regardless of the load. The bad news is that
it appears to be only 50% efficient.