Hello Ed, after replacing the capacitor and the resistor I now have a lock and I can tune it to 10 volts. When I measure near the VCO unit my counter shows a solid 386.7875MHz signal.
This time I programmed 2 eproms, one BIN and one HEX. Only the BIN worked. An now, after I realized why I received no signal from my RF-generator (I replaced the Dummy-Load cable with the one from the generator, hi) I can make the receiver tuning. Thank you very much Ed, you are a professional ! 73 Bernd --- In [email protected], wa6rqd <[EMAIL PROTECTED]> wrote: > > Bernd Maestling wrote: > > ok, so far so good. > > The RX-module won't work. The PLL don't lock, L1 voltage is low > > (0,16V) and on TP12 I have about 433MHz (also near the VCO). > > The TCXO is working ok. > > > > 73 > > Bernd > > DM5BM > > To receive at 431 the VCO will need to be at 431MHz-45MHz(1st IF) or > 386MHz. It was built to go from 395MHz to 440MHz. This may be below what > the VCO will tune without adding some capacitance. First try adjusting > the trimmer capacitor to the lowest frequency you can. If this is above > 386MHz, you will need the extra capacitance to get the VCO into the > correct range. Look in your manual near the back at the parts list for > the VCO for the differences between range C and range D. There are a few > capacitors and one resistor that are slightly larger on the D range. You > can either parallel some small chip caps or replace the current ones > with the new values. The coaxial resonator is also longer, but as you > are only going down to 431 the current one may be long enough. > > Try adding 1.5 pF across C7 on the RX VCO. > > > Once the VCO is going, you may find the helicals need to be lengthened also. > > > Ed Yoho > WA6RQD > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
