Radio Shack PRO-60 Service Manual page 14

Zeromatic Function Test Procedure
Zeromatic function operates when output is "H."
0 < el < e3 e3 < el < e2
e2 < el < Vcc
Output (D305 Cathode)
L
H L
To adjust voltage el, receive the signal in manual mode and:
• In AM/NFM mode, set T301 to obtain 1.0 ±0.1 volt DC at TP301.
• In WFM mode, set T302 to obtain 1.8 ±0.1 volt DC at TP301.
See "NFM/AM Discriminator Coil Alignment" and "WFM Discriminator Coil Alignment" on Page 11 and 12.
If the zeromatic does not function correctly, refer to "Reference Frequency Osc. Alignment" (Page 11), check that
the frequency is 1123.200000 MHz ±200 Hz, and adjust discriminator coil (T301, T302).
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