Pwr Supply Spike

Andy W3LI

When I first got my 6400M I would turn the 35 Amp power supply off after turning the Flex off. I noticed that when I turned the power supply ON a spike would light up the front panel light for just a millisecond ???  That bothered me so now I leave the supply ON and just shut the Flex OFF. However, there is a voltage on the control circuits with in the radio. 
I am thinking about putting a contactor in series with the leads and key that separately maybe with a slight time delay.
Any ideas or problems that you folks have would be appreciated.

Robert Lonn

I built a low current 12 volt DC power supply to FLOAT the voltage, Diode Isolated, so no feedback.. Now when I turn off my Main 35 Amp DC power supply the float voltage will keep the radio in Standby mode.. NOTE!!! Flex states that this FLASH you see will NOT harm the radio,, but I occasionally will see the radio fail to boot up correctly when you **** the DC power to the radio... Keep in mind that when you **** your power supply it will Bleed Off for a second or so,, but powering it on is instantaneous 12 volts.. You do get the FLASH as I call it of the front panel lights..

Robert

Andy W3LI

Float voltage is a great idea. The control circuits are hot and ready to work.
Tnx, Andy...W3LI

Andy W3LI

By any chance did you measure the current on the line with the radio off. I have some 12 vdc @ 500ma wall warts. Maybe???? 

Robert Lonn

No I did not,,, I used a 1.5 amp wall wart that was used to power a Netgear WiFi hub.. The standby voltage has to be very low,, but I never measured it???

Andy W3LI

Tnx Robert.

Harry Dudley

Hi Andy, I always turn off my Flex Radio before turning off the power supply.  Never have an issue of any type.  The only other item using the 12V pwr supply is my Palstar HF Auto Tuner.  I always turn off any connected item before turning off the12 V supply. 

Mark Erbaugh

My Flex 6700 has the GPSDO installed. With the radio plugged in to my supply, my inline Powerwerx meter shows a current of 0.17A.

Andy W3LI

Thank you Harry and Mark.

Patrick

Does the indicator light flash in response to inrush current from the primary input. Usually the inrush current is in response to the main filter caps on the DC side doing there initial charge up. This is assuming that you are using an analog PS. If the indicator is an OVP indicator then it could be over voltage spike triggering the OVP circuits.

Andy W3LI

Hi PAT, not sure what indicator light your are referring to. This is a very fast spike that is just enough to flash the panel lights. Yes, the caps have to charge and there is a delay until the regulator clamps,
No OVP indicator. Flex says not to be concerned. May try the idea of a float voltage.
TNX for your comments.

Patrick

I guess I interpreted the panel light flash as being the PS IT’s self. Thanks for your reply.

Andy W3LI

I thank u for being here.

Mike-VA3MW

That is normal and not an issue.  It is not a power spike and isn't a problem that needs to be worried about.  

Have you measured a spike coming from the power supply?

M

Andy W3LI

No longer have a scope fast enough to catch it.