Moto 4008B RIB DC Input Power

Terry_Glover · Post by **Terry_Glover** » Wed Dec 27, 2006 7:21 am

Would someone tell me what the DC output voltage is supposed to be for a Moto 4008B wall wart?

Einstein · Post by **Einstein** » Wed Dec 27, 2006 8:54 am

9 VDC 100mA

Terry_Glover · Post by **Terry_Glover** » Wed Dec 27, 2006 11:13 am

Thanks. I was about to put 12 volts to it. Glad I stopped and asked.

On the other hand, I wonder if the 12 volt power supply would have actually killed anything in the RIB?

kcbooboo · Post by **kcbooboo** » Wed Dec 27, 2006 12:00 pm

If you have sufficient funds available to buy another RIB and the radio you're programming, try 12V. Worst that can happen is you fry it and/or the radio it's attached to.

On the other hand, if you look at the schematic, perhaps it will give you an idea if 12V can be tolerated.

Bob M.

kb0nly · Post by **kb0nly** » Wed Dec 27, 2006 12:04 pm

On the Sandy Ganz rib i have it can take anything from 7-15v without trouble. It just depends on the rating of the onboard voltage regulator the original rib uses.

jackhackett · Post by **jackhackett** » Wed Dec 27, 2006 12:59 pm

This has been covered a few times already, this thread has a link to a wall wart that fits the bill perfectly:

http://batboard.batlabs.com/viewtopic.p ... t=rib+wart

Also, the original RIB regulator is a 78L05, which is the little TO-92 cased one. It'll take 12 volts, as the RIB is designed to operate off of SWB+ from the radio on some model radios.

Lake Effect · Post by **Lake Effect** » Wed Dec 27, 2006 1:47 pm

Got a 12 volt wall wart here about an arms length away that has powered our rib for the past 14 years that I know of. No problem yet.

Terry_Glover · Post by **Terry_Glover** » Wed Dec 27, 2006 1:58 pm

kcbooboo wrote: On the other hand, if you look at the schematic, perhaps it will give you an idea if 12V can be tolerated.

Bob M.

Do you see the input voltage on this schematic Bob M.? 4008B Schematic

DJP126 · Post by **DJP126** » Wed Dec 27, 2006 5:08 pm

Terry_Glover wrote:
kcbooboo wrote: On the other hand, if you look at the schematic, perhaps it will give you an idea if 12V can be tolerated.

Bob M.
Do you see the input voltage on this schematic Bob M.? 4008B Schematic

BT1 = 9 VDC
P2 pin 12 = approx 13.8 VDC

The input voltage is regulated down to +5 VDC. That is then sent to an inverter for the -5 VDC used by the two 2N3906 transistors. An input of 12 VDC at J1 should be OK.

Terry_Glover · Post by **Terry_Glover** » Thu Dec 28, 2006 6:34 am

The 12V wall wart worked fine. No issues and no "fried" RIB or MTS2000's.

Thanks for the straight answers.

Terry

RFguy · Post by **RFguy** » Thu Dec 28, 2006 6:46 am

Note: A 9 volt wall wart will be around 12 volts and a 12 volt wall wart will be 15 to 16 volts (they are non regulated and have a simple diode rectifier and cap inside).

The 12 volt wall wart will run fine, but it does increase the voltage drop across the 78L05 voltage regulator, therfore will increase the heat a bit (probably not enough to worry about).

If you had both and had to choose between them, a 9-volt wall wart would be a fine choice.

RFguy · Post by **RFguy** » Thu Dec 28, 2006 8:20 am

On a side note. We replace the diode in series with the battery (CR10) with a Schottky type. Standard 1N4007 is about 0.6 or 0.7 volts drop, where a Schottky is about 0.2 volt drop. It makes that battery useable to a lower voltage.
Diode part number is SR104DICT-ND from DigiKey.

http://en.wikipedia.org/wiki/Schottky_diode