Yaesu FT-901DM Maintenance Service Manual page 175

COUNTER UNIT (PB-2086A-3430/PB-2098)
The local oscillator signal is applied to Large-Scale
Integrated Circuit (LSI) chip for display on the
front panel digital display.
The premix signal as shown in Table 2 from the
LOCAL Unit, is amplified by Q3001 (3SK73), The
amplified signal is further amplified by Q3003(2SC
1674)and delivered to the LSI counter chip, Q3012
(MSM9520RS).
Qso03 is
of the output from
amplified by Qso0s (2SC1815Y) and
fed to gate 2 of Q3oo1 controlling the gain of those
amplifiers.
The output from the LSI is fed to the display. The
output from pins 24 through 30 is delivered to
segment drivers Q3o13—Q3o19 (2SA952L) and
digit drivers Qso06—Qso11 (2SA952L) through a
dynamic drive configuration. Display is performed
by D2901—D2906 (HP5082-7623), seven-segment
light-emitting diodes.
Tenn reenaenes Los B
160m 10.4875 — 10.987 10.486 — 10.986: MHz
[80m '12, 4875—12.9875 7 12.486—12.986
40m —-'15.9875—16, 4875 | 15.986—16. 486
30m | 18.9875—19.4875 18.986 — 19.486
20m | 22,9875 23.4875 2.98623. 486
17m | 26.9875—27.4875 26. 986 — 27.486
15m | 29,9875—30.4875 | 29.986 30.486
12m | 33.4875—33.9875 | 33,486—33.986
| toma | 36.9875—37.4875 36.986 —37. 486
[10m B | 37.4875~37.9875 37.486 37.986
lomC | 37.9875—38.4875 37.986 — 38. 486
38.4875 —38.9875 38.486 —38 986,
u Ss B cw, AM
10.489— 10.989! MHz 10. 4883— 12.9883) MHz
12.489— 12.989 | 12.4883—12.9883
15.989—16.489 if 15.9883 — 16. 4883 |
18.989—19.489 | 18. 9883—19. 4883
22.989 —23. 489 22, 9883 — 23.4883 |
26 .989— 27.489 26.9883 — 27. 4883
29.989—30.489 | 29.9883—30. 4883
33.489—33.989 33.4883 — 33.9883
36.989—37. 489 | 36. 9883-37. 4883 |
37. 489—37.989 | 37.4883 — 37.9883
37.989— 38.489 | 37.9883— 38.4883
38. 489— 38.989 | 38 4883 — 38. 9883
Table 2
PLL unit (PB-1709A)
4/eesu
TCs00:____— S99
*
Counter unit (PB-2086A)
5-8
4