Channel guard and NB problem

[sp5it]

I bought second hand CHG module. Problem is that when it is installed as Lou described: "Remove C57. (IN = L10, OUT = L11/C58.)" is working, but Noise Blanker action is very weak. Especially on SSB, radio is getting all the pulse noise around.
Lou wrote: "This is a common problem in all the Uniden and Uniden-clone SSB IF circuits, unless you follow our specific hookup locations" Can someone help me where is this location in my radio?
There is schematic: http://obrazki.elektroda.net/79_1282754357.png
Thank you very much, Mike sp5it

 

[jazzsinger]

if you remove c57,the input leg of filter goes to L10 side of c57 and the output leg of filter goes to L11 side of c57.gnd wire goes to circuit ground and +12v goes to either the 12v rail or the cold side of the on/of switch.

 

[sp5it]

I did that. NB is working much weaker because of CHG. That's the reason I asked.
The same filter mounted in Uniden PC122 have no influence with NB because of a little diffrent signal path.
Mike

 

[bob85]

sp5it,
lou always said place the filter before or after the nb loop to avoid nb problems, if you have it where c57 was then it is before the sample point for the nb, putting it in the same place in the pc122 puts the filter where lou says not to place it,
the nearest to mimicing your pc122 install without moving where the nb samples along the IF strip looks to be be in place of c58,
its hard to imagine that lou would talk about the nb issues when placing the chg within the nb loop then go on to instruct you to put the chg in the wrong place, double check your install, good luck.

 

[sp5it]

C57 if you will take a look to schematic is before NB loop. Than is L11 where NB is sampling and L12 signal from NB is coming back.
Now I have CHG in C57 place - before NB and L11.
Mike

 

[jazzsinger]

i would check the c57 you removed is the correct c57,by double checking it goes to L10 and L11,many uniden boarded radios had wrong markings on circuit boards.i ain't had a chance to look inside a president jack but believe its the same pc893 board as the stalker 9.i may be wrong.