Have this almost-new but out of warranty D-460Z camera. Everything
works perfectly, except the flash won't charge up.

I took off the cover and I see a flash capacitor, a little transformer,
a few surface-mount capacitors, a 3-mm sized transistor, a 1-mm
transistor (I think), and that's about it.

The bigger transistor has approx 5.2 volts on all its leads.

Anybody have any repair hints?
Anybody have a schematic for this circuit?


Thanks,

George

wrote in message
oups.com...
| Have this almost-new but out of warranty D-460Z camera. Everything
| works perfectly, except the flash won't charge up.
|
| I took off the cover and I see a flash capacitor, a little transformer,
| a few surface-mount capacitors, a 3-mm sized transistor, a 1-mm
| transistor (I think), and that's about it.
|
| The bigger transistor has approx 5.2 volts on all its leads.

While it's charging? Have you 'scoped it?

N

Have this almost-new but out of warranty D-460Z camera. Everything
works perfectly, except the flash won't charge up.

I took off the cover and I see a flash capacitor, a little transformer,
a few surface-mount capacitors, a 3-mm sized transistor, a 1-mm
transistor (I think), and that's about it.

The bigger transistor has approx 5.2 volts on all its leads.

Anybody have any repair hints?
Anybody have a schematic for this circuit?


Thanks,

George



My only hint is that the (main) capacitor in a strobe light is quite capable of
killing you. It can also irreversably remove a finger or two. It is also
capable of exploding like a blasting cap or 1/4 stick of dynamite and spraying
molten aluminum and boiling caustic liquids around the room. Give the thing a
LOT of respect...and if you're not sure what you're doing...don't do anything.

webpa

"NSM" writes:

wrote in message
oups.com...
| Have this almost-new but out of warranty D-460Z camera. Everything
| works perfectly, except the flash won't charge up.
|
| I took off the cover and I see a flash capacitor, a little transformer,
| a few surface-mount capacitors, a 3-mm sized transistor, a 1-mm
| transistor (I think), and that's about it.
|
| The bigger transistor has approx 5.2 volts on all its leads.

While it's charging? Have you 'scoped it?

The bigger transistor is probably the chopper. Since there's voltage on it,
probably good but check it.

Does the flash cap charge at all (should go to 300 V or os)?

Much more info and typical schematics in the Strobe FAQ at the site below.

--- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/
Repair | Main Table of Contents: http://repairfaq.ece.drexel.edu/REPAIR/
+Lasers | Sam's Laser FAQ: http://repairfaq.ece.drexel.edu/sam/lasersam.htm
| Mirror Sites: http://repairfaq.ece.drexel.edu/REPAIR/F_mirror.html

Note: These links are hopefully temporary until we can sort out the excessive
traffic on Repairfaq.org.

Important: Anything sent to the email address in the message header is ignored.
To contact me, please use the Feedback Form in the FAQs.

WEBPA wrote:


My only hint is that the (main) capacitor in a strobe light is quite
capable of
killing you.

Thanks, but may years ago I got a shock from a 400uf capacitor charged
to 450 volts. From hand to hand. It made me tremble for MANY
minutes. I've been really careful since then.


It can also irreversably remove a finger or two.

How? There's not that much charge in a 100uf 300V capacitor.


It is also capable of exploding like a blasting cap or 1/4 stick of
dynamite and spraying
molten aluminum and boiling caustic liquids around the room.

Now come on! Every electrolytic made since 1938 has some overpressure
release vent in the rubber end plug or score marks on the aluminum
case. I've blown a few electrolytics in my time and they all just made
a mild hiss and a bad smell. Nowhere near the pyrotechnics you
suggest!

( except if you insert the cap leads into the AC line plug, then you do
get a bit more fun ). But we're not doing that.

Regards,

grg


I think I'll just closr up the case and be glad I didnt fry anything
else. C amera works fine when in normal light.

WEBPA wrote:


My only hint is that the (main) capacitor in a strobe light is quite
capable of
killing you.

Thanks, but may years ago I got a shock from a 400uf capacitor charged
to 450 volts. From hand to hand. It made me tremble for MANY
minutes. I've been really careful since then.


It can also irreversably remove a finger or two.

How? There's not that much charge in a 100uf 300V capacitor.


Probably not in your specific case...but in a previous life, I was a military
corpsman on an Air Force base (among other places). There I learned that one of
the interesting things radar repaimen sometimes do is stick their fingers
between the leads of rather large capacitors. To make a long story short: In
six months, we had two folks arrive at the emergency room with 10 fingers
attached, 9 working. The 10th was usually removed fairly quickly to prevent
gangrene. Seems even a fairly low energy capacitor, given enough sweat on the
skin, can destroy most of the blood vessels in a finger.

It is also capable of exploding like a blasting cap or 1/4 stick of
dynamite and spraying
molten aluminum and boiling caustic liquids around the room.

Now come on! Every electrolytic made since 1938 has some overpressure
release vent in the rubber end plug or score marks on the aluminum
case. I've blown a few electrolytics in my time and they all just made
a mild hiss and a bad smell. Nowhere near the pyrotechnics you
suggest!

Again, didn't know the size of your capacitor, but I've still got a couple of
old Honeywell strobes in my attic that have much bigger caps. And one I saved
for parts after it exploded on my workbench and started a fire across the room
where the molten aluminum hit a pile of plastic boxes. Granted, there are
pressure relief devices built in, and they usually work...but every few million
(what...a week's global production?) or so it ain't going to work.


( except if you insert the cap leads into the AC line plug, then you do
get a bit more fun ). But we're not doing that.


Glad to hear you're not doing that on purpose.

Regards,

grg


I think I'll just closr up the case and be glad I didnt fry anything
else. C amera works fine when in normal light.



If the camera has an external flash connection (some do...most don't), you may
still be able to work in the dark.
webpa

I had some underwater strobes that weren't charging. The voltage accross the
cap is usually around 300 to 350 volts. If you aren't hearing the oscillator
squealing and not getting the high voltage on the cap, I would suspect the
transistor, but of course don't rule out simple things like the diodes,
connections, etc. In my case, one unit had a broken solder joint, one a bad
transistor, etc. And yes be very careful when poking around if the caps are
charged. Mine has three 1100 microfarad caps in parallel, and one slip burnt
the end of a 6mm screw driver away. I got replacement caps from Rubycon in
Chicago, Ill. Be sure to use photo grade replacements as normal electrolytics
aren't designed for repeated, very quick discharge-charge cycles.