Figure 16. Tuning unit 1 rf oscillator, mixer, and oscillator, simplified schematic diagram.

Figure 16. Tuning unit 1 rf oscillator, mixer, and oscillator, simplified schematic diagram.

must be used to assure that a 1,600-kc incoming rf

t h e rf section (and therefore the if. amplifier) at

signal does not saturate the 1,600-kc if. amplifier

the undesired incoming frequency of 1,600 kc. The

a n d thereby produce erroneous meter indications.

t u n e d circuit introduces a degenerative rf voltage

Tuned circuit L1 and C59 operate as an absorption

i n the cathode circuit of V1 at the 1,600-kc fre-

w a v e t r a p , drastically decreasing the response o f

quency.