Hei Mooly just noticed your signature ....i begin to like you more and more every day
I get a bit of stick over it when I start playing with Spice files on here
Appreciate all the replies!!
I removed the output transistors and they check OK. I reinstalled them thinking well maybe there was a bad connection between them and the board. Problem still exist. But what I did notice was that when I tap the output board while playing the receiver, there is a crackling noise each time I tap. Bad solder joint somewhere or bad component?
I removed the output transistors and they check OK. I reinstalled them thinking well maybe there was a bad connection between them and the board. Problem still exist. But what I did notice was that when I tap the output board while playing the receiver, there is a crackling noise each time I tap. Bad solder joint somewhere or bad component?
'tis a strange problem for sure. Well I think your next line of attack has to be to see why it crackles when you tap the board. I'm assuming you haven't a scope, which would really be the correct approach as you could see what was going on.
Also as a whacky thought, is the speaker OK. If it were measuring low impedance it could give these symptoms although not of course the physical issue with the pcb. Had to ask
Also as a whacky thought, is the speaker OK. If it were measuring low impedance it could give these symptoms although not of course the physical issue with the pcb. Had to ask
Whilst considering solder joints and components etc. how are the power, ground and output connections to the board? Some old amplifiers used a variety of systems from a thru-hole solder joint like any component, to inserted pins and wire-wrap posts and these can become loose and just as faulty as any loose connection. 'worth a look anyway.
FIXED!!
It turns out that there was a small section by one of the driver transistors that had lifted up slightly from the board and not making good contact. I found it while probing with my test lead. This was causing the crackling sound when tapping the board and the original problem. Thanks to everyone for their input!!!
It turns out that there was a small section by one of the driver transistors that had lifted up slightly from the board and not making good contact. I found it while probing with my test lead. This was causing the crackling sound when tapping the board and the original problem. Thanks to everyone for their input!!!
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