I have one of the subject radios that seems to have developed some sensitivity issues especially in the lower frequency ranges: 450mHz. on down. However, the problem is not consitent throughout the bands. For example, I am now listening to local Bristol, VA police on 155.590 but I cannot listen to 155.490 which is also a local SW Virginia police dept. Also, when keying on 146.52 on a radio right next to the RX, the squelch will not open on the RX even though it is tuned to that freq. Actually, sometimes the squelch will open but what comes out is uninteligible but sometimes a portion of the repeater squelch tail can be heard.
I have also noticed as the day has worn on that the squelch control is becoming more and more less effective. I have had to apply more and more gain for it to become effective.
I have called AOR and they no longer support this radio because of parts availability (or lack thereof). Taka at AOR told me that the problem is probably with NEC chip MC5800 which is 6 pin low band amplifier.
I guess what I am trying to ask here is does anyone know anyone thqat can repair this RX or perhaps a source or cross reference for the chip?
EDIT: I forgot to request a schematic and parts list with circuit board layout...anybody?
EDIT: I found a service manual and schematic. Also have a better discription of the required IC: It is a hybrid, wideband amplifier IC.
Any help would be greatly appreciated.
I have also noticed as the day has worn on that the squelch control is becoming more and more less effective. I have had to apply more and more gain for it to become effective.
I have called AOR and they no longer support this radio because of parts availability (or lack thereof). Taka at AOR told me that the problem is probably with NEC chip MC5800 which is 6 pin low band amplifier.
I guess what I am trying to ask here is does anyone know anyone thqat can repair this RX or perhaps a source or cross reference for the chip?
EDIT: I forgot to request a schematic and parts list with circuit board layout...anybody?
EDIT: I found a service manual and schematic. Also have a better discription of the required IC: It is a hybrid, wideband amplifier IC.
Any help would be greatly appreciated.
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