I have a 16 channel GP300 when I try to program it, channels 1-4 are correct but duplicate on channels 5-8 and channels 9-12 are correct but they duplicate on channels 13-16. Aside from this, the radio functions properly. I do not believe this is a problem with the radio as it also happens on another GP300.
I am using RSS version 80.02.00 on an OLD Toshiba laptop with a RIB I built myself using a board from Sandy Ganz. I did not buy a kit, I ordered all of the parts through Mouser and made my own interface cable...I do not believe the problem is with either of those unless maybe I have a bad resistor or diode or even a bad transistor.
Thanks!!
GP300 programming problem
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It certainly sounds like the channel selector switch has gone bad. What you describe makes perfect sense if one of the binary inputs from the switch to the processor was broken. For example:
0000 = ch 1_____________0010 = ch 5
1000 = ch 2_____________1010 = ch 6
0100 = ch 3_____________0110 = ch 7
1100 = ch 4_____________1110 = ch 8
As you can see from the above table, the only difference between channels 1-4 and 5-8 is the 3rd digit. If it's stuck at zero, then channels 5-8 will be the same as 1-4.
0001 = ch 9____________0011 = ch 13
1001 = ch 10___________1011 = ch 14
0101 = ch 11___________0111 = ch 15
1101 = ch 12___________1111 = ch 16
Again, as you can see, the 3rd digit is the only binary difference between channels 9-12 and 13-16.
You either have a bad switch, or there is a broken connection between one of the channel selector pins, and it's corresponding microprocessor pin.
Todd
0000 = ch 1_____________0010 = ch 5
1000 = ch 2_____________1010 = ch 6
0100 = ch 3_____________0110 = ch 7
1100 = ch 4_____________1110 = ch 8
As you can see from the above table, the only difference between channels 1-4 and 5-8 is the 3rd digit. If it's stuck at zero, then channels 5-8 will be the same as 1-4.
0001 = ch 9____________0011 = ch 13
1001 = ch 10___________1011 = ch 14
0101 = ch 11___________0111 = ch 15
1101 = ch 12___________1111 = ch 16
Again, as you can see, the 3rd digit is the only binary difference between channels 9-12 and 13-16.
You either have a bad switch, or there is a broken connection between one of the channel selector pins, and it's corresponding microprocessor pin.
Todd
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One other possibility that I've run across occasionally: There is a chip capacitor to ground on each of the bit lines between the selector switch and the uP inputs, and I've found a shorted cap on one of the bit lines(don't remember which one). Does the possibility of a bad lot of chip caps(I think they are .01 uF) sound like a better bet to you than defective switches? On the last one that I serviced I pulled the switch before I realized that the cap described above had shorted.
gondzur wrote:The model number is P93YPC20C2AA, the date code is 95/5/18. What are the odds of having this same problem on 2 radios though? Both are the same model number and same date code. Thanks.
Ryan
The odds of having two bad switches (or even broken chip capacitors) in 10-year old radios is far greater than the RSS being the source of your problems. I have never seen RSS be the culprit in a case like this.
Todd
No trees were harmed in the posting of this message...however an extraordinarily large number of electrons were horribly inconvenienced.
Welcome to the /\/\achine.
Welcome to the /\/\achine.