home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Ham Radio
/
Ham Radio CD-ROM (Emerald Software) (1995).ISO
/
kenwood
/
ken_mods
/
ts430s.4
< prev
next >
Wrap
Text File
|
1990-08-26
|
2KB
|
53 lines
TS430S.4
FROM: N0HME
SUBJECT: TS430 AGC MOD
--QRX!--
--LOADING (3)--
THE AGC MOD ON THE TS430 KENWOOD TO RUN
AMTOR REQUIRES THREE COMPONENT CHANGES.
ON THE IF BOARD--FIND AND REPLACE
CAPACITOR C-60, A 10 MFD, WITH A 4.7
MFD. CLIP ONE OF THE CONNECTIONSNON
DIODE D-50. REPLACE CAPACITOR C-164, A
0.22 MFD, WITH A 0.1 MFD CERAMIC. BOTH
D-50 AND C-60 ARE ON THE UPPER LEFT
CORNER OF THE IF BOARD AND ARE ALSO
MARKED ON THE PC BOARD. HOWEVER...C-164
IS NOT MARKED CLEARLY. IT IS A 0.22 MFD
CAN ELECTROYLTIC NEAR THE CENTER OF THE
IF BOARD. IT IS JUST BELOW AND TO THE
RIGHT OF C-149 AND IS DIRECTLY RIGHT OF
IC-5. LOOKING AT THE BACK OF THE BOARD,
ONE LEAD OF C-164 IS CONNECTED TO THE
JUNCTION OF A 47K OHM RESISTOR (R-129)
AND A GLASS DIODE (D-77). THESE TWO
COMPONENTS ARE ALSO NOT MARKED ON THE
PC, BUT ARE SOLDERED TO THE BACK OF THE
BOARD.
ONE OTHER NICE TOUCH WAS TO PUT IN-LINE
WITH DIODE D-50, A SHORT PIECE OF COAX
TO A MINIATURE TOGGLE SWITCH. THIS
DISABLES THE MOD, SO THAT THE SMOOTH
CHANGE OVER FROM TRANSMIT TO RECEIVE
THAT THE 430 NORMALY HAS, CAN BE
RESTORED WHEN ULTRAFAST RECOVERY IS NOT
SO IMPORTANT. IN CW, WITH D-50 CLIPPED,
THE RECEIVER KICKS BACK TO LIFE WITH A
SHARP CRACK AND GETS ANNOYING WHEN THE
GAIN IS REALLY HIGH, CHASING AFTER A
WEAK DX STATION --FOR INSTANCE. SO THE
EWITCH REMOVES DIODEHD-50 FOR AMTOR AND
RETURNS IT TO THE CIRCUIT FOR ANYTHING
ELSE.
BEWARE! EVERYTHING IS VERY TINY,
VERY CROWDED, AND VERY EXPENSIVE.
73S DE KA0SUN RELAYED BY...N0KGX...GENE