What's wrong with this picture? Galaxy 979

[loosecannon]

I'm going to post a frequency modification that is on cbtricks for the Galaxy 979 series.

I believe there is a major piece of information missing from this page, and i wonder if anyone else will catch it.
of course there is always the very real chance that i am the one missing something LOL.


if no one seems interested in a few hours then i will post what i think i see missing.
LC

 

[sonoma]

I have never seen one of these radios but always curious about the bottom trace cut with the 4.7k resister across the one trace. figured it may have a jumper to pin 16. not ever seeing one of these radios made me wonder about that portion of the cut trace. plus do not see a lead going to any of the switches for the lower resister.
not having a radio to look at made me wonder what was missing.. take it you have a radio there to look at.

 

[nomadradio]

What's missing is a reminder of the need for center-off switches. Only way to obtain your normal 40 channels with this setup, both switches in center position.

And no, you can't get "all" the RC channels with a simple SPST switch. Requires a center-off switch to do that, as well. One side of the switch to ground for going down one channel. Only works on channels with an odd-numbered binary to the chip. The other side of the switch goes to pin 9, to force pin 16 high, so you can go up one channel from the even-numbered binary channel codes.

Just can't get all the RC's with a single switch throw on this chip. Have to have a way to force the chip up one channel, and down one channel both.

73

 

[loosecannon]

ding ding ding!

nomad wins it!
as if anyone is surprised LOL.

yes, the switch that is used for pin 11 needs to be a SPDT center off three position switch.
otherwise you can't get the normal 40 channels.

luckily i deciphered the need for it before i attempted the mod.

the pin 10 switch can just be SPDT two position since it is high all the time in the normal 40.
LC