G07 Blows F901 on Startup

Fudd

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title says it all...just put in a new hot, hooked it up and immediately blew the small fuse....i looked for shorts on the board and couldnt find any...

also i know now the filter cap has a charge...how do you bleed that off? i know i can do it with a screw driver but whats the light bulb method? hold a bulb to one of the 3 solder points for the cap?
 
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Did you put the insulator on the HOT? Are you powering it up with an isolation transformer? Are the legs of the HOT - or the wires attached to it - touching the frame at all?
 
insulator on the hot and checked it.....iso transformer...legs of the hot are clear from the frame and wires are clear and on the end of the hot.

is the hot fried again from that fuse blowing?

also how do i bleed the filter cap with a light bulb?
 
Usually F902 (small fuse) blows for a HOT issue. F901 usually blows due to a power problem, but not always...
 
pics of the hot and vr....i did a continuity check on the outside to make sure the insulators were good..
 

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still blowing f901 small fuse....put in a new hot, new insulator and swapped ic501 from another board, new VR and insulator and it still blows the fuse.
 
still blowing f901 small fuse....put in a new hot, new insulator and swapped ic501 from another board, new VR and insulator and it still blows the fuse.


Have you replaced the flyback yet?
 
yup its a new flyback.....looked for shorts on the soldering as well and found nothing....what else could blow that fuse?
 
shorted diodes?

d905 which is right above the b+ adjustment has no reading so i'm going to replace that...any other suggestions...i'm down to my last small fuse, if it blows again i'll have to wait until i order more from riptor.
 
d905 which is right above the b+ adjustment has no reading so i'm going to replace that...any other suggestions...i'm down to my last small fuse, if it blows again i'll have to wait until i order more from riptor.

Get one of the fuse circuit breakers for issues like this...
 
you got a link at mouser? or radioshack?

replaced that diode, checked the rest of the diodes and she still blew the fuse...i need to get that circuit breaker.
 
have you checked x901.....it feeds the power supply regulator and it it's bad it will blow the fuse.
 
I use a "light bulb fuse" for situations like this. 100W bulb, either soldered to an old fuse with wire leads, or alligator clips with wire leads. If it comes on bright - and stays on bright - when you power it up, there's a short. Leave it on for more than a few seconds though, as the resistance of the bulb cuts down the current a lot. The capacitors will need a minute to charge. Assuming that all is well, the bulb will dim within a few seconds and the monitor will operate - though as a lower voltage (thanks to the bulb).
 
here's a pic of the breaker i got from bob today...its a 3amp..what a great idea.


connected it to each end of the fuse, started it up....breaker didnt trip and smoke started coming out of the flyback....3 amp is too much?
 

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Flybacks bad out of the box is rare, but it happens. I've heard of a bad batch of K7000 flys, but this is the first G07 I've heard of that smoked.
 
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