9V Battery as Power Supply...?

[ameerat42]

Preface: DARRT and BLARRSTT!

It has happened again that my camera is losing date and time on battery change.
This is also bad because apart from the inconvenience of having to set it again
each time, a fix means languishing without it while it holidays in Japan for a couple
of months.

MOST IRKSOME TOO, is that Sigma Japan's fix - a new capacitor on mainboard -
only lasted about 18 months. The only "good" thing about it was the reasonable
cost of $120.

Workaround:
So hooking it up to a power supply before removing the battery will retain the
date/time/other info. But the thing is the PS is overpriced at $161 (https://sigmaphoto.com.au/products/eya022/sigma-sac-4-ac-adapter#in-the-box) here in Oz.
(It's even cheaper in NZ :p)

The specs say (https://www.bhphotovideo.com/c/product/1023875-REG/sigma_eya024_sac_4_ac_adapter_for.html/specs) it puts out 9V DC at 3 A.

Additional Info:
I cannot charge the battery in-camera. It must be placed in an external dock.

The Question:
What if I hooked up a simple 9V battery to the appropriate plug and used that to
hook into the DC-IN of the camera during battery change-over? It takes ~ 5 sec
to change the battery.

Are there any technicalities I should be aware of?

[nardes]

As with any external power supply project, I would make sure that I have the correct voltage and polarity to minimise the risk of blowing anything up.

Various items of astronomy equipment I have use 3, 5, 9, 12 and 24V DC, with some inputs Centre +ve and a couple Centre -ve, so I have labelled all the cables to minimise the risk of over voltage damage when plugging stuff in, especially in the dark.

Cheers

Dennis

[ameerat42]

I might have to put the battery to one side, as I just found this (https://www.jaycar.com.au/9v-dc-3a-power-supply-7dc-plugs/p/MP3496) - made to order :eek:

--And better than a 1000 chickens (going "cheep").

[Boo53]

I might have to put the battery to one side, as I just found this (https://www.jaycar.com.au/9v-dc-3a-power-supply-7dc-plugs/p/MP3496) - made to order :eek:

--And better than a 1000 chickens (going "cheep").

If you are checking out Jaycar it might be worth trying to see if they still make a unit like that which is also voltage switchable. I've got one (in a draw, somewhere) had it awhile so may not make them anymore

[ameerat42]

John.
This one?
https://www.jaycar.com.au/3-12v-dc-12w-power-supply-7dc-plugs-and-usb-outlet/p/MP3312

[Boo53]

John.
This one?
https://www.jaycar.com.au/3-12v-dc-12w-power-supply-7dc-plugs-and-usb-outlet/p/MP3312

Pretty much. Mines older and has a slider to set the voltage rather than that dial. I'd say the dial would be a much more secure way of setting it.

With the way it connects the heads its possible to change the polarity of the connections

[Hawthy]

Take additional care with this. I bought a very similar thing to power a digital radio after the original lead gave up the ghost. You attach the different plugs to the main lead by way of two pins that plug into the lead. Be very careful that you have them the right way around because I accidentally reversed them and it stuffed my battery, which cost about $60 from memory.
EDIT: Just read John's post and clearly I reversed the polarity.

[ameerat42]

Ta, Hawthy. Yes, I am aware of the changeable polarity on the pins, as I
also had one years ago. It will be only for the purpose of powering my
camera, and I will hot-glue the correct plug on permanently :nod: