On Oct 3, 2006, at 1:35 PM, <[EMAIL PROTECTED]> <[EMAIL PROTECTED]> wrote:
---- Tod Glenn <[EMAIL PROTECTED]> wrote:
On Oct 1, 2006, at 10:34 AM, Ron D'Eau Claire wrote:
Tod, look for a short in the +12 circuit to ground. The swollen
batteries
suggests they were feeding lots of current into a dead short for a
long
time.
All checked out OK
I just completed the voltage checks on page 27 of the assembly manual
Here's a comparison of the results when working versus now
U1 pin 1 was 4.94v now 19.5mV
U3 pin 6 was 6.05v now 2.47v
D2 Anode was 14.83v now 2.7v
D2 cathode was 13.75v now 2.5v
Voltage measured at the supply is 12.3v (Astron AS-35)
Tod,
Take a look at the power cable and the power connector, J1. If you
measure 12.3V at the supply, you should measure very close to that
at the anode end of D2 unless there is an open or high resistance
in the power cable or in connector J1 or the PC board traces from
J1 to D2-anode or a short circuit in that area that is "pulling"
the supply voltage down. Try disconnecting the power cable from the
supply and measuring the resistance from the "+" supply lead to D2-
anode to check the path for continuity. If it's not very close to 0
ohms, something is wrong.
There's no continuity between + and the D2 anode
Do the same with the supply "-" lead to a ground (one of the
mounting standoffs should work). That path should also be very
close to 0 ohms. While your measuring, measure from the power cable
"+" to "-" to insure it's not shorted.
If you do find an open or a short in the power path and it's not a
soldering defect, look again for a short circuit on the "V+" signal
line shown on the schematic. Check this by measuring the resistance
from L3 on the bottom of the board to one of the mounting
standoffs. (This would be the first step on page 55 of the assembly
manual). If it measures less than 500 ohms, there is a short circuit.
The resistance between L3 and ground is about 1 K.
----
Tod Glenn
N7WD
NAQCC #1283
SKCC #1444
FISTS #12134
ARCI #12420
[EMAIL PROTECTED]
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