a/c adaptor
Posted 29/01/2011 - 17:56
Link
8V might be a bit high. The batteries are going to be a maximum of 6V. Remember having let the smoke out, how hard it is to get it back in.
Posted 29/01/2011 - 18:03
Link
I'm aware of the properties of magic smoke, I've let enough out in my time
The supply socket on my K10 explicitly says 8.3V.
I'm thinking I could actually take a 7808 and keep it *really* simple; duty > 3A shouldn't be *that* high. Heatsinking is not a problem.
Though hold on, isn't this one of your specialist subjects?
Bret
The supply socket on my K10 explicitly says 8.3V.
I'm thinking I could actually take a 7808 and keep it *really* simple; duty > 3A shouldn't be *that* high. Heatsinking is not a problem.
Though hold on, isn't this one of your specialist subjects?
Bret
my pics: link
my kit: K3, K5, K-01, DA 18-55, D-FA50 macro, Siggy 30/1.4, 100-300/f4, 70-200/2.8, Samsung 12-24/f4, Tamron 17-50, and lots of other bits.
my kit: K3, K5, K-01, DA 18-55, D-FA50 macro, Siggy 30/1.4, 100-300/f4, 70-200/2.8, Samsung 12-24/f4, Tamron 17-50, and lots of other bits.
Posted 29/01/2011 - 18:07
Link
more reading indicates an LM1084 would probably be a better solution. I could then sink the TO220 to a 'sink connected to the outside of a metal case and also power it with three 6V SLA batteries if necessary.
Bret
Bret
my pics: link
my kit: K3, K5, K-01, DA 18-55, D-FA50 macro, Siggy 30/1.4, 100-300/f4, 70-200/2.8, Samsung 12-24/f4, Tamron 17-50, and lots of other bits.
my kit: K3, K5, K-01, DA 18-55, D-FA50 macro, Siggy 30/1.4, 100-300/f4, 70-200/2.8, Samsung 12-24/f4, Tamron 17-50, and lots of other bits.
Posted 29/01/2011 - 22:31
Link
Just had a look at the K-x destructions and it doesn't seem to specify voltage for an AC supply. Unlike other Pentax(e)s (Pantaces?) the input is connected directly to the battery terminals. The batteries are going to produce 4.8-6V.
That LM1084 looks a useful bit of kit. We tend to be stuck with 78s or 317s at work. TBH, with the silly price of pre-built units I wouldn't bother building one.
For those who are wondering about the smoke of which we speak, it is smoke that makes electric things work.
Don't believe me? What happens when the smoke leaks out? It stops working.
That LM1084 looks a useful bit of kit. We tend to be stuck with 78s or 317s at work. TBH, with the silly price of pre-built units I wouldn't bother building one.
For those who are wondering about the smoke of which we speak, it is smoke that makes electric things work.
Don't believe me? What happens when the smoke leaks out? It stops working.
Posted 30/01/2011 - 10:11
Link
yep, and the grip for the k5 will take 6 AAs, meaning 7.2V top end.
I'm interested in building one for one reason only: make two and run one off 12V for the car and another off 230 for the home - and since I have two bodies soon, it would be nice to be able to make use of the sync functionality in Remote Assistant. At least that's my thinking...
Bret
I'm interested in building one for one reason only: make two and run one off 12V for the car and another off 230 for the home - and since I have two bodies soon, it would be nice to be able to make use of the sync functionality in Remote Assistant. At least that's my thinking...
Bret
my pics: link
my kit: K3, K5, K-01, DA 18-55, D-FA50 macro, Siggy 30/1.4, 100-300/f4, 70-200/2.8, Samsung 12-24/f4, Tamron 17-50, and lots of other bits.
my kit: K3, K5, K-01, DA 18-55, D-FA50 macro, Siggy 30/1.4, 100-300/f4, 70-200/2.8, Samsung 12-24/f4, Tamron 17-50, and lots of other bits.
Posted 30/01/2011 - 15:02
Link
is there actually a battery grip for the kr?
I will let you guys in on a secret...
the best way to built a power supply for your camera...
start with one of these:
brand not important... but if you need weather proof light and emergency power, why carry more than you need to????
for a video d-slr user, that is just brilliant!
I will let you guys in on a secret...
the best way to built a power supply for your camera...
start with one of these:
brand not important... but if you need weather proof light and emergency power, why carry more than you need to????
for a video d-slr user, that is just brilliant!
Fired many shots. Didn't kill anything.
Posted 30/01/2011 - 16:04
Link
Don wrote:
is there actually a battery grip for the kr?
I will let you guys in on a secret...
the best way to built a power supply for your camera...
start with one of these:
brand not important... but if you need weather proof light and emergency power, why carry more than you need to????
for a video d-slr user, that is just brilliant!
great idea. And comes with integral AF assist light!!!
is there actually a battery grip for the kr?
I will let you guys in on a secret...
the best way to built a power supply for your camera...
start with one of these:
brand not important... but if you need weather proof light and emergency power, why carry more than you need to????
for a video d-slr user, that is just brilliant!
[i]Bodies: 1x K-5IIs, 2x K-5, Sony TX-5, Nokia 808
Lenses: Pentax DA 10-17mm ED(IF) Fish Eye, Pentax DA 14mm f/2.8, Sigma 17-70mm f/2.8, Pentax-A 28mm f/2.8, Sigma 30mm F1.4 EX DC, Pentax-A 50mm f/1.2, Pentax-A 50mm f/1.4, Pentax-FA 50mm f/1.4, Pentax-A 50mm f/1.7, Pentax DA* 50-135mm f/2.8, Sigma 135-400mm APO DG, and more ..
Flash: AF-540FGZ, Vivitar 283
Lenses: Pentax DA 10-17mm ED(IF) Fish Eye, Pentax DA 14mm f/2.8, Sigma 17-70mm f/2.8, Pentax-A 28mm f/2.8, Sigma 30mm F1.4 EX DC, Pentax-A 50mm f/1.2, Pentax-A 50mm f/1.4, Pentax-FA 50mm f/1.4, Pentax-A 50mm f/1.7, Pentax DA* 50-135mm f/2.8, Sigma 135-400mm APO DG, and more ..
Flash: AF-540FGZ, Vivitar 283
Posted 04/02/2011 - 20:03
Link
so, anyone got some circuits to try? I'd like to get my first one sorted before the week after next, which means ordering parts on Monday....
Bret
Bret
my pics: link
my kit: K3, K5, K-01, DA 18-55, D-FA50 macro, Siggy 30/1.4, 100-300/f4, 70-200/2.8, Samsung 12-24/f4, Tamron 17-50, and lots of other bits.
my kit: K3, K5, K-01, DA 18-55, D-FA50 macro, Siggy 30/1.4, 100-300/f4, 70-200/2.8, Samsung 12-24/f4, Tamron 17-50, and lots of other bits.
Posted 04/02/2011 - 20:55
Link
OK, worked it out. It'll be an LM338 using a standard NatSemi application circuit in a Bopla box with a standard Heatsink. Have to see if it gets too hot / need a metal box...but it shouldn't in -10
Parts will be ordered for Tuesday delivery and then I can get on with it and test it on my K10D and then the K5 and then a K-x. Are the connectors the same on all?
Bret
Parts will be ordered for Tuesday delivery and then I can get on with it and test it on my K10D and then the K5 and then a K-x. Are the connectors the same on all?
Bret
my pics: link
my kit: K3, K5, K-01, DA 18-55, D-FA50 macro, Siggy 30/1.4, 100-300/f4, 70-200/2.8, Samsung 12-24/f4, Tamron 17-50, and lots of other bits.
my kit: K3, K5, K-01, DA 18-55, D-FA50 macro, Siggy 30/1.4, 100-300/f4, 70-200/2.8, Samsung 12-24/f4, Tamron 17-50, and lots of other bits.
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1470 posts
17 years
Work: Helsinki; Home: Lahti
There is one other thing you need to be aware of with mains power supplies and electronic equipment. As well as watching for the maximum load, you can get regulated and un-regulated plug top power supplies.
You will need the right sort!
Bret
my kit: K3, K5, K-01, DA 18-55, D-FA50 macro, Siggy 30/1.4, 100-300/f4, 70-200/2.8, Samsung 12-24/f4, Tamron 17-50, and lots of other bits.