Batboard

What I need to program a gp-300 radio? . I have RIB and GP-300 RSS, But do not know what is the suitable cable? . Batlabs show a schematec for gp300 / p110 programming cable pinout. Is this cable used for programming with or without RIB ? Thanks for your help.

Thanks nand. I test it and it is working fine. Thank you again.

Add a wire from the 7.5 volt point on the programming adaptor to pin 12 on the RIB connector and that will also power your RIB from the same source as the radio gets it's 7.5 volts.
Maybe someone could up-date the nice schematic.

"Add a wire from the 7.5 volt point on the programming adaptor
to pin 12 on the RIB connector and that will also power your
RIB from the same source as the radio gets it's 7.5 volts. ..."

Will it work in reverse? (i.e. Power from the RIB to the radio via pin 12).

NO ! there is a diode in the RIB.
My bench supply, 3A max, set to 7.2 V powers the radio for testing and pgmg. I did make up a old GP300 chassis to slide the battery on to power the radio in the field. The orig M programming adapter had a slide on adapter on the back to take a battery, but costs WAY TOO MUCH!!

My programming adapters are made from a battery, cells removed, and a gold plunger contact for the programming pin. One also has a 7.2 volt regulator and reverse polarity protection so the radio and RIB can be powered from a 12 volt source. This one is used in the field.

from http://www.batlabs.com/gp300.html it mention that
"Sometime in 1994 Motorola changed the 2 channel radios such that if you were to hack the radio into an 8 channel
model, you still get 2 channels. The change was the microprocessor to a new unit that only recognizes the common and 1 line of
the channel selector. The channel switch is the same regardless of which radio you have. Only by changing the CPU can you
then change the number of channels to more than 2. To tell if you can convert your radio, pop the knob off and turn the
selector. If the 2 channels programmed in the radio come up in the order 1,2,2,2,2,2... it will work. If they come up
1,2,1,2,1,2,1,2... forget it, you'd probably have to change the microprocessor to get it to work. "

Q1. and my gp300 is come up with 1,2,1,2,1,2, channel,and i has try to program my gp300 with the hex edit way.and i fail to expand my 2 channel to 16 channel.any idea how to solve this problem,other than change the CPU.if not,than whice CPU i need to change.

Q2. the 1 set gp300 i have is i bought from second hand shop,and it is without charger.i can't afford to buy a new charger.i'm looking for the gp300 charger schematic or other similar charger that is good to charging 7.5volt Ni-Cd battery.
although i bought this walkie-talkie personally,but the use of this walkie-talkie is on my st.john ambulance association activiti/duty,so i hope some one can kindly give/donate a old but use-able gp300 charger for me.thank you.
our division is form up less than one year,still looking for company that can donate us walkie-talkie,our division need more walkie-talkie because our number of member increase and duty is getting more,we need a better communication and control.

Q3. any idea how to build a power supply adaptor for gp300,so i can use it as base station in indoor without using battery.like other mobile radio.our wall-plug power supply is 240volt.

hopefully i can get all the help i need here.
i'm from MALAYSIA.
thanks in advance.

"Q3. any idea how to build a power supply adaptor for gp300,so i can use it as base station in indoor without using battery.like other mobile radio.our wall-plug power supply is 240volt."""

Check the previous post, using an old battery with the cells removed and a 7.5 volt regulator. This can be feed then from a 12 volt power source, like a car battery.

" has a 7.2 volt regulator and reverse polarity protection so the radio can be powered from a 12 volt source. This one is used in the field."
There are also commercial "battery eliminators" available.

i can't find it,can you tell me what keyword should i search.