16-10-2021, 03:12 PM
I spent a little time on the TV today. I had another look at the choke that was mounted on the speaker. I has initially thought it was wired in parallel with the choke mounted on the underside of the chassis.
But on closer examination of the wiring that is not the case. I guess the fact that it was mounted on the speaker should have been a clue. The TV would have been originally have been fitted with energised speaker and at some point it failed and was replaced with a permanent magnet type. The choke was us ed to take the place of the energising coil.
Some of the wiring around the choke area is not matching the circuit diagram. How it is at present I cant see it being correct so it will need to be changed back.
The diagram I am working from can be found here. I note that at least some of the information there was provided by out own Geordie McBoyne. A big thank you goes to Geordie McBoyne as it is proving most useful.
It would be nice to refit a energised speaker. I had a search and found one potential candidate of the correct size. I have no idea what it is out of as it was given to me but most lightly a radio of some sort. The cone is a little tore but is salvageable. The speaker coil has continuity. As does the energising coil but I may need to rewind it to suit the higher current of the TV HT.
Frank
But on closer examination of the wiring that is not the case. I guess the fact that it was mounted on the speaker should have been a clue. The TV would have been originally have been fitted with energised speaker and at some point it failed and was replaced with a permanent magnet type. The choke was us ed to take the place of the energising coil.
Some of the wiring around the choke area is not matching the circuit diagram. How it is at present I cant see it being correct so it will need to be changed back.
The diagram I am working from can be found here. I note that at least some of the information there was provided by out own Geordie McBoyne. A big thank you goes to Geordie McBoyne as it is proving most useful.
It would be nice to refit a energised speaker. I had a search and found one potential candidate of the correct size. I have no idea what it is out of as it was given to me but most lightly a radio of some sort. The cone is a little tore but is salvageable. The speaker coil has continuity. As does the energising coil but I may need to rewind it to suit the higher current of the TV HT.
Frank
