Sam's
Well i see this listed ..
TRC-421 (21-1536)..................273
Wonder how different the 421 and 421A are
Anyone's got the 421 then ?
ps got the full lc7131 Sanyo data sheet. I checked it's operation earlier on , the chip seems to react correctly , i see the keying , switch for channels are ok i see it go hi lo changing channel switch setting pins 1 to 5 .. but at the VCO out pin 17 i got 6.3 some volt stable and no change when i change channels .. the VCO seems simply dead . i hear my generator set to 455khz modulated through the speaker . rf section is ok so are all the if's
so my big guess is that the VCO somehow is dead .would explain why tx and rx are dead .. injecting a signal to the tx chain gives an output on the rf jack .. ill keep checking in that area pulling silicon as needed. Anyways .. back to the lab in the morning.
Well i see this listed ..
TRC-421 (21-1536)..................273
Wonder how different the 421 and 421A are
Anyone's got the 421 then ?
ps got the full lc7131 Sanyo data sheet. I checked it's operation earlier on , the chip seems to react correctly , i see the keying , switch for channels are ok i see it go hi lo changing channel switch setting pins 1 to 5 .. but at the VCO out pin 17 i got 6.3 some volt stable and no change when i change channels .. the VCO seems simply dead . i hear my generator set to 455khz modulated through the speaker . rf section is ok so are all the if's
so my big guess is that the VCO somehow is dead .would explain why tx and rx are dead .. injecting a signal to the tx chain gives an output on the rf jack .. ill keep checking in that area pulling silicon as needed. Anyways .. back to the lab in the morning.