Hi all!
Fist of all I would like to say that this will be my first post and that this is a superb site! Good job!
The problem with the Lincoln is no power on FM/AM whatsoever. On SSB the is a very slight noticeable signal on an external reciever. This all seemed to have happened during a mild thunderstorm where a QSO wasn't possible all of a sudden presumably caused by static electricity.
The rest is working as far as the receiver and MPU go...
I received the Lincoln in this state without the final where as the owner thought the culprit might be the final and unsoldered it. Before replacing any transistor I checked if there was any bias but none whatsoever... Maybe the bias diode gave way so I unsoldered the diode and it indeed was defective so it needed to be replaced. After this I tried to get a 50 mA reading between TP4 and TP3 but nothing yet. So I decided to place a brand new MRF477 there were the original was missing and do the test again. At that point I got stuck in finding the reason for this problem... At first my power supply went in a safe mode due to short-circuit :shock: . So I got the Volt meter on the two TP's and measured 13,89V between TP4 and TP3...? Is this normal? I don't have to guess what happens when the test pcb is placed back in this condition... :?
I have to say that I'm confident in making myself sure about the soldering job and checked all solder connections over and over again... I'm not a expert on this particular radio but I can do a lot to get a radio working again like many defective radio's before this Lincoln came along. But in order to avoid making matters worse I really hope that someone could give me a hint where to look for... If I made a stupid mistake or assumption... tell me :|
I just want to get this radio working again and I know I'm a step away... hopefully....
Any help would be very much appreciated!
Cheers!
John
Fist of all I would like to say that this will be my first post and that this is a superb site! Good job!
The problem with the Lincoln is no power on FM/AM whatsoever. On SSB the is a very slight noticeable signal on an external reciever. This all seemed to have happened during a mild thunderstorm where a QSO wasn't possible all of a sudden presumably caused by static electricity.
The rest is working as far as the receiver and MPU go...
I received the Lincoln in this state without the final where as the owner thought the culprit might be the final and unsoldered it. Before replacing any transistor I checked if there was any bias but none whatsoever... Maybe the bias diode gave way so I unsoldered the diode and it indeed was defective so it needed to be replaced. After this I tried to get a 50 mA reading between TP4 and TP3 but nothing yet. So I decided to place a brand new MRF477 there were the original was missing and do the test again. At that point I got stuck in finding the reason for this problem... At first my power supply went in a safe mode due to short-circuit :shock: . So I got the Volt meter on the two TP's and measured 13,89V between TP4 and TP3...? Is this normal? I don't have to guess what happens when the test pcb is placed back in this condition... :?
I have to say that I'm confident in making myself sure about the soldering job and checked all solder connections over and over again... I'm not a expert on this particular radio but I can do a lot to get a radio working again like many defective radio's before this Lincoln came along. But in order to avoid making matters worse I really hope that someone could give me a hint where to look for... If I made a stupid mistake or assumption... tell me :|
I just want to get this radio working again and I know I'm a step away... hopefully....
Any help would be very much appreciated!
Cheers!
John
...runna pile-up on 6m SSB