Tait T800 SL2 25W - Page 81

M8SL2-00-002-812 T855 Fault Finding B5.15
© Copyright Tait Electronics Limited August 2004. All rights reserved.
Y
N
Y
Y
Y
Y
N
Y
Y
Y
C
Noisy synth; poor
selectivity &/or
poor residual FM.
Correct DC V
present on Q1 VCO?
Change trimmer;
still noisy?
Change Q1;
still noisy?
Change TCXO;
still noisy?
Change varactors;
still noisy?
Replace VCO
assembly.
Synthesiser OK.
N
N
N
N
Check inductors,
biasing resistors
& Q1.
Replace if faulty.
Go to B.
Loop filter &
components around
op. amp. (IC750) OK?
N
VCO phase locked?
3-16V present on
control line?