[GreenKeys] Crystals for autostart operation

[Russmill47 at aol.com]

One thing to add in addition to George's comment about FT-243  crystals.  
 
If you want to buy crystals for FSK and 170 shift, remember that you lower  
the frequency of the transmitted signal when you go to space. While the Net  
frequency is almost always the Mark frequency, you need to be aware that you  
want to lower the crystal frequency with your Frequency Shift Keyer when  you go 
to space.
 
Therefore, you should purchase your crystals with the space, and not the  
mark frequency, in mind.  
 
A recommendation is to order your crystals for 170 shift as mark  frequency 
minus 100 Hz.  
 
For example. If you want to hit 14080.000 using 170 shift and your  
transmitter doubles up from 40M:
 
14080.000  - 0.100 = 14079.900 
 
14079.900 / 2 = 7039.950
 
This will keep both the mark and space frequency close to the designed load  
limit of the crystal.
 
Also, here is a link to the International Crystal website:  
_http://www.icmfg.com/_ (http://www.icmfg.com/) 
 
For additional details, see Crystal Controlled RTTY, RTTY  Journal, December 
1967, Page 4.
 
73,
 
Russ 
WA3FRP