Tech Advice Needed

[Jay Bass]

Hi
I am looking for a replacement 9v DC Adaptor for a Nady pem EO3 iem transmitter
it states DC+ 9v 200 mA.
what does the 200 mA mean ?
i pressume milli amps is it ok to get a adaptor that is above or below this rating ?
also do i need to make sure the polarity is + .

i notice my zoom adaptor is 9v but - polarity and 300mA ?

any help appreciated
Regards
Jay

[ecca]

It must be the same as,or greater than 200ma and + usually means tip positive, this usually being displayed somewhere on the power supply itself as a little picture of the connector,

[Didier]

Hi
I am looking for a replacement 9v DC Adaptor for a Nady pem EO3 iem transmitter
it states DC+ 9v 200 mA.
what does the 200 mA mean ?
i pressume milli amps is it ok to get a adaptor that is above or below this rating ?
also do i need to make sure the polarity is + .

i notice my zoom adaptor is 9v but - polarity and 300mA ?

any help appreciated
Regards
Jay

You may use an adaptator with a higher mA rating, but not lower, so a 300 mA adapator for a 200 mA device should be OK, of course with DC you have to check polarity (center plug positive or negative), and you have also to check the size of the plug.
Generally the center plug is +.



if it's not indicated on the device itself, it should be indicated on documentation. Universal replacement DC adaptors are generally supplied with various removable plugs of different sizes, and the possibility to invert polarity.


Didier

[RogerCook]

Hi Jay

You're right mA= milliamps. 9v is the voltage.

So you need a power supply that will deliver a minimum of 200mA at 9v. I had a quick look at the Nady website - http://www.nady.com/eo3.html - . It seems the adaptor is a regulated power supply. This means that it will supply exactly (well within acceptable tolerance at least) 9 volts at 200mA. An unregulated supply rated at say 300mA 9v might deliver more than 9v at lower current demands (eg200mA), so to be safe you really need a regulated supply with the right voltage and current ratings. A higher current rating should be OK with a regulated supply as the device it is powering will only draw whatever current it needs but if the supply is not capable of supplying the required current (eg if you attempt to draw 200mA from a 100mA supply) the voltage is likely to drop to below the stated value. The polarity is important. You need to ensure the inner contact and outer sleeve iof the plug are connected the right way round. The diagram on P5 of the manual shows the centre pin of the power socket on the transmitter marked + (positive) so the inner of the plug must be positive too. It won't work if it's connected the other way round, though I'd expect the transmitter to have protection against incorrect polarity to prevent damage. There is also a variety of connector sizes so you need to make sure a replacement supply has the correct size to match the transmitter (I can't find the size in the manual).

It might be worth having a word with these guys who I've used in the past and were very helpful

http://www.effectpowersupplies.com/

Hope this helps

Roger

[Jay Bass]

Thanks for all the help guys
i have more idea what to look for now.

regards
Jay