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MM3NRX
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If you have one of these radios, probably in time it will suffer from PLL unlock state, the usual dots on the display and the CW letters U & L, ..-.-..

A friend of mine had this problem, so reading the service manual and a quick look at the diagram, I concluded that the VCO2 was in unlock status, as all the band refused to fire up. On the other hand if your radio only tx on certain bands you will have to also check the VCO volts per VCO for the banbd coverage. All details are in the service manual on this site. Back to the "all band no TX/RX" state, it was found that the VCO was at only 3.37 volts, with no frequency display, I adjusted TC1 in VCO2 Circuit (X58-3390-03)so the voltage was back to 5.00 vdc and the display fired up. I noticed the VCO voltage at around 4 volts was enough to lock this radio up, but prob not to 40 Mhz.

To gain access to VCO2, remove top lid, remove the speaker mount screws and unplug speaker, remove screws on the Carrier unit and pull upwards out of the way, the lid of the PLL tank should be removed now and inside you will see VCO2 Circuit in a small metal square box. TP3 is the ref point for voltage reading and TC1 is under the small hole on the bottom right, be careful as this device is to be turned slowly and in small incremements, as this device is very narrow in voltage spread, but it will be achieved.

2 days later and the radio is still working...quick and easy cure...

As I said before if you can not use just say, 7-10 Mhz then adjust the voltage on the relevent VCO.

MM3NRX - Jason - Dundee - Scotland - IO86LL