[NLRS] Question on OCXO Integration

[W0ZQ at aol.com]

GM Mike.   I have not done this mod, but I did review my manual  & schmatic 
and can offer the following suggestions:

1.  Did you  try to measure any output power ?   If you have output power 
then  there is something going on in the receive side.   If you have no  output 
power and no transverter noise on receive, then its most likely something  to 
do with the LO work your doing.
 
1a)  Any possibility that the injection freq (from your external LO)  is that 
much different in freq from the original Xtal that the LO multipler  chain 
needs to be retuned ??   (F1, F2, F3, F4, F5).   If  so, the tune up is easy per 
the manual.

2.  Closely inspect the area  where you removed the onboard Xtal .... no 
solder bridges.   Use a low  power magnifying glass to closely inspect both sides 
of the  board.

3.  Check closely where you inject the external LO signal  onto the PCB.   On 
my documentation (far bottom right side picture on  Figure 4) that is also 
the spot where the PTC goes if your using the internal  XTAL .... the PTO uses 
+Vcc and ground so how can that spot be used as a  floating pin for connecting 
any external LO ??   It may be OK in that  you have to wire it with +12vdc 
when using a PTC, but if you WERE using a PTC  there, check it out as its most 
likely not floating but is connected to GND or  Vcc. 

4.  Check out the new 100pf coupling cap that you added ....  solder looks OK 
?   I've had those crack on me.   In  desperation, replace it with a new one. 
  
 
5.  In desperation, haywire your LO signal directly to the junction of  220R 
& Z10 (like the picture shows) and see if it works.   Use a  100pf cap in 
series with your haywire injection (like the schematic  shows).  


Hope this helps.   Its gotta be something obvious as it  was working and the 
mod is pretty benign.

73, W0ZQ