[amsat-bb] 1)Kansas City Tracker / Tuner (hardware/software) , 2) Source PSKModem .

[USSatCom@xxxxxxx]

RE: -KANSAS CITY TUNER / TRACKER (HARDWARE/SOFTWARE CONCERNS ) 
       -SOURCE PSK MODEM COMPATABLE WITH MFJ-1270CQ , TNC/2 CLONE ,
               (RS-232 and TTL interfaces and DIN connector )  .

You may have a fixed omnidirectional antenna system with no nulls that works 
fine
for SK type orbital transponders ( DIGITAL 9600 baud , Mode J , FSK )  . And 
you
have a crossband  FM ( F2E , F3E ) , 2 M. UPLINK , 435 CM. DOWNLINK , 
tranciever . Its not a 2500 dollar all mode satalite transciever , it only 
has the 
AFO (1200 baud jack ) and the 9600 baud ( discriminator modulator ) stereo 
jack on
on the back for packet work , and up/down ptt pins on the mic connector for 
any sort of automatic doppler correction (ADC) .  Your nominal 9600 baud 
modulation voltage p-p wold be about 2 volts . The 11 kHZ max doppler 
deviation on the 435 cm downlink may effect your packet signal operation . 
You would like to enable automatic doppler correction but the 250 dollar 
Kansas City Tracker hardware card resideing in your computers ISA slot has no 
rotor I/O load on the serial port . Your software emulation gives you error 
messages : tracker driver not loaded , and you  can't use it to just enable 
the Tuner portion of the product package . Your  serious  about  packet 
satalite work , but on a reasonalbe budget and not a rediculous one . You 
have invested no larger somes of money for directional antennas that are 
computer tracked , nor even in sideband operational modes .  You ask LL Grace 
what can be done . They say other highly experinced amateurs have designed 
their own circuits to enable just the ADC . They say many have been based on 
Easy Com software designs and they monitor the intial discriminator voltage 
for deviation or change due to doppler effects , then convert this deviation 
to up / down ptt mic commands . Doppler on 2 meters may be 4 KHZ , no big 
deal , thats less than one ptt click on your tranceiver at its smallest up 
/down step setting . At 436 MHZ it may be 11KHZ and thats plus or minus two 
clicks . You may loose something here at this point . At the higer 
frequencies it may be plus or minus a dozen cliks or more durring a pass . 
Now a big deal (and deviation) . If anyone knows of any design or schematic , 
or even the designer, him (her) -self  , or any source of I/O cuircits / 
software, like these that may enable just ADC "Tunning" ,  independent of 
rotor control , please contact me at :

                           ANTHONY W. WOISLAW , KB1EJZ .
                           1063 SHED HILL ROAD 
                           STODDARD , N.H. 
                           03464+4444   (USA) 
                           PHONE/ MAIL / FAX : 603-446-4307
                           USSatCom@AOL.COM .
   
I am also looking for any PSK MODEM BOARD COMAPATABLE WITH THE MFJ-1270CQ , 
9600 baud FSK , TNC/2 CLONE . I was told PacCom used to make one that might 
interface with the with the MFJ board but may no longer do so  ( I did write 
to them ) . Maybe there are some used  ones still out there but I did write 
to  them .
  
73-
THANK YOU !!!!  KBIEJZ .    

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