CONNEX 4800 NO RECIVE OR TRANSMIT

[simpleman]

i have a 4800 connex that i left on for a couple of days and when i went to talk on it i no longer have recive or transmit the finals and driver all ck good as well as the am voltage regulator i have no recive on usb or lsb or fm any ideas on what could be wrong with this radio? thanks in advance for your help

[Rick]

I do not have the schematic diagram for the radio, but if it is the same as the 4400 check Q37 this transistor is bolted to the right hand side of the radio near the front, the Collector should be at 8.40 volts Emitter 13.8 volts and the Base 13.00 in SSB mode it is the most likely fault causing on RX / TX. Let us know how you get on.


Rick.

[simpleman]

well have checked the voltage as you sugested and all ck ok any other ideas. i should also add that i do have talk back and about a 1/4 watt transmit on the meter.

[Rick]

Check transistors Q30, 31 and 33 also what voltage have got at the Emitter of Q45 and the collector also let me know what volts you have at pin 7 of IC7 in RX and TX.

Rick