Hi
I have been having a lot of trouble with this radio but have now finally got it working with a replacement ferrite rod and coils from a similar KB KR023 radio.
When the radio arrived the ferrite rod had jumped out of its mounts and was loose in the case. The coils appeared OK, and the rod looked OK as well, but later I found that MW was very quiet and rather intermittent when I was adjusting the MW coil for the low frequency alignment.
I checked and there was a small amount of flexing in the rod.
The rod is covered in what looks like a heat shrunk plastic sleeve and the clean break in the ferrite was also under several layers of original looking tape.
I removed the tape and made a ring cut around the plastic sleeve about an inch from the now visible break. It was was then possible to pull the 2 halves of the rod apart and add a couple of drops of superglue to the joint and realign it in the tube. This should have worked fairly well, but this was when I found that there were also hairline damage to the Litz wire on the MW coil.
The coil is supposed to measure about 2 ohms but my damaged one was measuring about 11 ohms, so although it had continuity some of the 5 separate strands of the litz wire were damaged. MW was working but it was quiet and difficult to align the radio.
This leaves me with the task of repairing the ferrite rod to put back in the KB KR023, or finding a replacement one with MW coil. (I have put a request in the wanted section)
Its early days yet, but if nothing turns up I will have rewind the MW coil myself.
Finally I come to my question, what difference will it make if I rewind the coil with ordinary enamelled copper wire of the same overall diameter as the litz wire, 0.7mm?
Thanks
Mike
I have been having a lot of trouble with this radio but have now finally got it working with a replacement ferrite rod and coils from a similar KB KR023 radio.
When the radio arrived the ferrite rod had jumped out of its mounts and was loose in the case. The coils appeared OK, and the rod looked OK as well, but later I found that MW was very quiet and rather intermittent when I was adjusting the MW coil for the low frequency alignment.
I checked and there was a small amount of flexing in the rod.
The rod is covered in what looks like a heat shrunk plastic sleeve and the clean break in the ferrite was also under several layers of original looking tape.
I removed the tape and made a ring cut around the plastic sleeve about an inch from the now visible break. It was was then possible to pull the 2 halves of the rod apart and add a couple of drops of superglue to the joint and realign it in the tube. This should have worked fairly well, but this was when I found that there were also hairline damage to the Litz wire on the MW coil.
The coil is supposed to measure about 2 ohms but my damaged one was measuring about 11 ohms, so although it had continuity some of the 5 separate strands of the litz wire were damaged. MW was working but it was quiet and difficult to align the radio.
This leaves me with the task of repairing the ferrite rod to put back in the KB KR023, or finding a replacement one with MW coil. (I have put a request in the wanted section)
Its early days yet, but if nothing turns up I will have rewind the MW coil myself.
Finally I come to my question, what difference will it make if I rewind the coil with ordinary enamelled copper wire of the same overall diameter as the litz wire, 0.7mm?
Thanks
Mike
