Galaxy DX66v3 Mod limiter location

[Rc123]

Does anyone know where the modulation limiter is inside a Galaxy dx66v3? Wanting to do the Npc mod to it.

 

[sp5it]

R249

 

[Rc123]

Thank you very much. I assume I just put a diode there with the resistor if I’m correct?

 

[NZ8N]

Removing or cutting R249 merely disables the AMC. The diode goes somewhere else. I do not condone disabling the AMC or ALC circuits, because this is what causes 99% of the hash, trash, splash and bleedover in other people's receivers. The AMC responds to Negative going voltage swings. A properly set up NPC-RC on an Oscilloscope will allow you to reduce your carrier, and have higher positive peaks, up to the positive rail, before it flat-tops. The Negative going voltage swings will (should) never hit Zero volts, where the RF is cut off in between syllables. Some even go to the extent of "Box Cars" where the RF comes out in square wave pulses, which cause a lot of audio harmonics. By leaving R249 intact, this gives you some amount of automatic feedback adjustment to keep it from being overmodulated.

 

[Shadetree Mechanic]

The limiter attack speed can be lowered so it doesn't clamp as hard when it kicks in. Should be very similar to the 86v.

Galaxy DX86V mods

Careful is showing off your work @Shadetree Mechanic - you'll find yourself with a lot of buyers wanting a piece of you...

www.worldwidedx.com

 

[Rc123]

R249

Would you happen to know the Npc mod for it to make sure I do it right?

 

[sp5it]

Do you have schematic for that version? Is it much different than v1?

 

[Rc123]

Do you have schematic for that version? Is it much different than v1?

I can’t find one. Should be the same as a connex 33hpc1 it’s kinda like a 86v also somewhat without ssb

 

[Rc123]

Do you have schematic for that version? Is it much different than v1?

It’s a whole different board eptdx2912z also the same as a galaxy dx55f. If I can remember right

 

[Rc123]

Do you have schematic for that version? Is it much different than v1?

Wanted to give a update. Followed the instructions you posted awhile back on the galaxy 86v and they worked. Thank you my friend.