Hi all
I'am having some probs with this MC3359 NBFM IF System.
If you look at the mc3359 test circuit, you will see that X1, C14,
FL1 and C12 are connected to VCC(6v), while in the circuit that i built
(i found on the net) has X1, C14, FL1 and C12 are connected to gnd, which
one is right ??
In both circuits the AFC and Scan Control are NOT used!
I am using a Marconi 2955b test set, freq set to 10.7Mhz with a 1Khz tone
@1mV output.
The one that i made works, but seems to have little gain, the squelch sort
of works, but when i adjust the squelch pot i get different audio levels, and
sometimes the level seems to drift away (can't hear the 1Khz tone)
Any thoughts on these circuits ??
Regards
Howard
I'am having some probs with this MC3359 NBFM IF System.
If you look at the mc3359 test circuit, you will see that X1, C14,
FL1 and C12 are connected to VCC(6v), while in the circuit that i built
(i found on the net) has X1, C14, FL1 and C12 are connected to gnd, which
one is right ??
In both circuits the AFC and Scan Control are NOT used!
I am using a Marconi 2955b test set, freq set to 10.7Mhz with a 1Khz tone
@1mV output.
The one that i made works, but seems to have little gain, the squelch sort
of works, but when i adjust the squelch pot i get different audio levels, and
sometimes the level seems to drift away (can't hear the 1Khz tone)
Any thoughts on these circuits ??
Regards
Howard
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