HELP Astron 70 amp PS
 

HELP Astron 70 amp PS
I have a astron 70 amp power supply and was hooking up a transmitter
to it and I pulled the power supply closer to me and the positive wire
came loose and hit the ground terminal on power supply.
Now when I turn it on you can hear the power supply turn on and the
light on the power swithch comes on, but no volts comes up on the
meter. I checked the terminals on the back and no volt, very little if
at all.
The outside fuse is good.
I took off top cover and I don't see and internal fuse.
Is there a diode I should be looking for?
I'm sure it has to have some kind of protection if the wires are
reversed.
Any help would be great.
Rich

wrote in message
...
HELP Astron 70 amp PS
I have a astron 70 amp power supply and was hooking up a transmitter
to it and I pulled the power supply closer to me and the positive wire
came loose and hit the ground terminal on power supply.
Now when I turn it on you can hear the power supply turn on and the
light on the power swithch comes on, but no volts comes up on the
meter. I checked the terminals on the back and no volt, very little if


Check to see if any or all of the pass transistors are shorted. If so the
crowbar may be kicking in and keeping the output voltage low. Doubt this is
the case as the fuse would probably blow. Otherwise check the 723 voltage
regulator IC and see if it is putting out any voltage. YOu may just have to
change it out as that seems to be a weak point of the supplies.

wrote in message
...
HELP Astron 70 amp PS
I have a astron 70 amp power supply and was hooking up a transmitter
to it and I pulled the power supply closer to me and the positive wire
came loose and hit the ground terminal on power supply.
Now when I turn it on you can hear the power supply turn on and the
light on the power swithch comes on, but no volts comes up on the
meter. I checked the terminals on the back and no volt, very little if


Check to see if any or all of the pass transistors are shorted. If so the
crowbar may be kicking in and keeping the output voltage low. Doubt this is
the case as the fuse would probably blow. Otherwise check the 723 voltage
regulator IC and see if it is putting out any voltage. YOu may just have to
change it out as that seems to be a weak point of the supplies.

wrote in message
...
HELP Astron 70 amp PS
I have a astron 70 amp power supply and was hooking up a transmitter
to it and I pulled the power supply closer to me and the positive wire
came loose and hit the ground terminal on power supply.
Now when I turn it on you can hear the power supply turn on and the
light on the power swithch comes on, but no volts comes up on the
meter. I checked the terminals on the back and no volt, very little if


Check to see if any or all of the pass transistors are shorted. If so the
crowbar may be kicking in and keeping the output voltage low. Doubt this is
the case as the fuse would probably blow. Otherwise check the 723 voltage
regulator IC and see if it is putting out any voltage. YOu may just have to
change it out as that seems to be a weak point of the supplies.

In article . net,
"Ralph Mowery" wrote:

Check to see if any or all of the pass transistors are shorted.

Bzzzt, wrong, would you like to try for what is behind Door #3?

If the Pass Transistors were shorted, you would see the voltage of the
filter capacitors and rectifiers on the output. He stated that he had
"No or little output voltage". This would indicate that the Pass
Transistors are OPEN, blown that way by the High Current when the output
was shorted, or the rectifiers are blown OPEN and not producing any
DC to the filter caps.


Me

In article . net,
"Ralph Mowery" wrote:

Check to see if any or all of the pass transistors are shorted.

Bzzzt, wrong, would you like to try for what is behind Door #3?

If the Pass Transistors were shorted, you would see the voltage of the
filter capacitors and rectifiers on the output. He stated that he had
"No or little output voltage". This would indicate that the Pass
Transistors are OPEN, blown that way by the High Current when the output
was shorted, or the rectifiers are blown OPEN and not producing any
DC to the filter caps.


Me

In article . net,
"Ralph Mowery" wrote:

Check to see if any or all of the pass transistors are shorted.

Bzzzt, wrong, would you like to try for what is behind Door #3?

If the Pass Transistors were shorted, you would see the voltage of the
filter capacitors and rectifiers on the output. He stated that he had
"No or little output voltage". This would indicate that the Pass
Transistors are OPEN, blown that way by the High Current when the output
was shorted, or the rectifiers are blown OPEN and not producing any
DC to the filter caps.


Me

In article ,
Me wrote:

Check to see if any or all of the pass transistors are shorted.

Bzzzt, wrong, would you like to try for what is behind Door #3?

If the Pass Transistors were shorted, you would see the voltage of the
filter capacitors and rectifiers on the output. He stated that he had
"No or little output voltage". This would indicate that the Pass
Transistors are OPEN, blown that way by the High Current when the output
was shorted, or the rectifiers are blown OPEN and not producing any
DC to the filter caps.

It's still darned good advice. If there's a fuse or fusible component
between the DC filter caps and the pass transistor, it might very well
have blown if the pass transistor shorted during an overload.

From what I've heard, bipolar power transistors are as likely to fail
shorted as they are to fail open.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

In article ,
Me wrote:

Check to see if any or all of the pass transistors are shorted.

Bzzzt, wrong, would you like to try for what is behind Door #3?

If the Pass Transistors were shorted, you would see the voltage of the
filter capacitors and rectifiers on the output. He stated that he had
"No or little output voltage". This would indicate that the Pass
Transistors are OPEN, blown that way by the High Current when the output
was shorted, or the rectifiers are blown OPEN and not producing any
DC to the filter caps.

It's still darned good advice. If there's a fuse or fusible component
between the DC filter caps and the pass transistor, it might very well
have blown if the pass transistor shorted during an overload.

From what I've heard, bipolar power transistors are as likely to fail
shorted as they are to fail open.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

In article ,
Me wrote:

Check to see if any or all of the pass transistors are shorted.

Bzzzt, wrong, would you like to try for what is behind Door #3?

If the Pass Transistors were shorted, you would see the voltage of the
filter capacitors and rectifiers on the output. He stated that he had
"No or little output voltage". This would indicate that the Pass
Transistors are OPEN, blown that way by the High Current when the output
was shorted, or the rectifiers are blown OPEN and not producing any
DC to the filter caps.

It's still darned good advice. If there's a fuse or fusible component
between the DC filter caps and the pass transistor, it might very well
have blown if the pass transistor shorted during an overload.

From what I've heard, bipolar power transistors are as likely to fail
shorted as they are to fail open.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!