One of our agency's Spectras was taken out of service today. It suddenly just quit receiving (in the middle of a transmission, no less), and was taken to the shop. The tech said that "the oscillator wasn't hitting the second injector". Can anyone provde a more detailed explanation? That's the first thing to go wrong with the radio in years...it was just recently reinstalled into a new cruiser.
Thanks!
Gordon
Spectra repair question
Moderator: Queue Moderator
You didn't say what band the radio operated in. On the 800 Mhz radios, there is a ceramic substate front end section. The filtering and injection is all done on the ceramic substate.
The injection signal is part of the receiver. It is generated by the micro computer on a local oscillator frequency determined by what frequency your receiving at. Double it, subtract the IF frequency and this is what they mix against the incoming RF frequency from the antenna.
The injection signal comes via a cable from another board. It is possible that the cable fell out. It is very small and has a push on kind of connection. I have never seen one of these come loose.
Have seen the front end substate be damaged by a heavy shock to the radio. Like throwing a jack on top of the radio. The radio being dropped on the pavement.
Not a very detailed explanation of your question. Hope it gets your question answered.
Jim
The injection signal is part of the receiver. It is generated by the micro computer on a local oscillator frequency determined by what frequency your receiving at. Double it, subtract the IF frequency and this is what they mix against the incoming RF frequency from the antenna.
The injection signal comes via a cable from another board. It is possible that the cable fell out. It is very small and has a push on kind of connection. I have never seen one of these come loose.
Have seen the front end substate be damaged by a heavy shock to the radio. Like throwing a jack on top of the radio. The radio being dropped on the pavement.
Not a very detailed explanation of your question. Hope it gets your question answered.
Jim