hi
yes it can be done HOWEVER ..
40 channel am plla02a switches come in two flavors either N224>N286 (ch1>ch40 dont worry about the inverted codes in this example ) or N330>N286 (ch1>ch40) depending on chassis it came from...
now heres the bite
ssb pll02a radios use N255>N211(ch1>ch40) so as you can see the Ncode or binary weighting presented to the pll would put the radio on a different frequency to what you intend
Ah OK, I thought there might be a catch.
5 ways around this
either replace the mixer crystal in the radio(after replacing with a pll02a am switch to correct the frequency of the radio in other words shift it back to the correct fcc band (expensive in this day and age)
or
put a binary adder in between the new channel switch and the pll to correct the binary weighting (4008) (20 bucks with a board and some resistors)
or use a pic ic programmed to correct the binary weighting ..both of those options will allow more bands to be added (about 20 bucks)
or old school way a eeprom with code to correct binary weighting
by correct binry weighting i mean convert say 330>286from switch in to 255>211 that the pll needs to be on correct ch1>ch40
as you can see its not "simple"
switches from other radios with differnt plls will be the same issue
i have done may hybrids swaps to radios that you cant get 40 channel switches for converting from 18/23 channel to 40 but always you need to use one of the above methods to correct either the frequency or the code presented to the pll to get back on the band required
Thanks for all that info, Mike! That's a lot of food for thought, and educational as well.
of course the "simple" way is just throw a digimax in it but i guess your intention is stock 40 channels which i am sure you are well aware of ..ray at razor radio can do the install and hes playing with a pllo2a to mc145106 conversion at moment if you really want more channels
This is interesting, I hadn't heard of this guy, thanks. I was thinking about a Digimax, but looking at the install in a GE B model, that is on You Tube () kind of puts me off, all that mess of wires and the drilling and cutting.
end of day just buy a wrecked ssb chassis (plloa2) from usa where 40 channel switches are common
I have been looking, not many around, only the odd AMer, hence my question. I would also be worried that the switch is worn to death.[/QUOTE]