TS-430S PLL Unlock at High Temperatures (Revision)

Author: Trio-Kenwood Communication, inc.

 This service bulletin supercedes bulletin 891, which concerned low input level to IC-16 as the radio warmed up. This bulletin incorporates information contained in Bulletin 891 plus additional information.

PROCEDURE:

On the Control Unit (X53-1290-XX)


Check transistor Q8. If it is not a 2SC1815Y change it to this type (Serial numbers 408XXXX-509XXXX).

For serial numbers before 408XXXX change R29 to 820 ohms and C41 to 100 pF.



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In addition to the changes listed above check for the following signals:
(You must check these at a dial frequency of exactly 14.000.000 MHz)

TP-1 6.0v (L18 adjusts)
TP-2 70 MHz
TP-3 45.3 MHz
TP-4 6.35v (L10 adjusts)

Time required for this modification is 1 hour or less.
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(Click to enlarge)



GW1NGL NA7KR Kevin Roberts Ham Radio

Page last updated on 09/10/2012 by Kevin Roberts NA7KR a colection of Ham Radio and Electronic Information