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staticmind · 17th Sep 2020, 5:56 pm

Hi German Dalek,

Thank you for the advice. I succeeded with connecting the AW53-88 up to the other chassis. The same bright raster is shown, and the voltages are identical and still much too high. About 120V on the cathode!
I will perform more measurements, but that will be with the other non-working AW43-88 connected instead.

Using a Müter BMR7, both CRTs measure about the same in emission (low/poor), but the brightness of the two CRTs (when the AW43-88 worked) is about the same. This leads me to conclude that the voltages have been off all the time, especially G1 and G2. G2 is for example around 500V!

The AW53-88 based Capri has much less use and the PCBs basically look like new, also behind the sockets. As the cabinet is in pretty poor condition, my plan is to replace the electrolytics and film caps and move it to the 17" Capri cabinet.

I'll need a new (old) working AW43-88. Luckily, they are not so rare a find at least in the Netherlands and Germany, but in Denmark, I'm probably 40 years too late. I found an untested Telefunken AW43-88 in Germany, but with missing scan coils. It seems from the data sheets that the Philips AW43-88 scan coils can be used without any issue as the curvatures seem to be very close.
In order to fit a new CRT I'll have to remove the support band that goes around the edge of the CRT, and I'm actually a bit terrified thinking of doing that, as I understand it the CRT has no built in implosion protection. Is the purpose of this band to add any protection to the CRT at all or is it just to add holes and standoffs for fixing the CRT to the cabinet? Back in the days, did service technicians need to re-use the band as the CRT was delivered without one?

17th Sep 2020, 5:56 pm	#78
staticmind Tetrode Join Date: Sep 2019 Location: Aalborg, Denmark Posts: 97	Re: B&O Capri 606 TV (17") restoration Hi German Dalek, Thank you for the advice. I succeeded with connecting the AW53-88 up to the other chassis. The same bright raster is shown, and the voltages are identical and still much too high. About 120V on the cathode! I will perform more measurements, but that will be with the other non-working AW43-88 connected instead. Using a Müter BMR7, both CRTs measure about the same in emission (low/poor), but the brightness of the two CRTs (when the AW43-88 worked) is about the same. This leads me to conclude that the voltages have been off all the time, especially G1 and G2. G2 is for example around 500V! The AW53-88 based Capri has much less use and the PCBs basically look like new, also behind the sockets. As the cabinet is in pretty poor condition, my plan is to replace the electrolytics and film caps and move it to the 17" Capri cabinet. I'll need a new (old) working AW43-88. Luckily, they are not so rare a find at least in the Netherlands and Germany, but in Denmark, I'm probably 40 years too late. I found an untested Telefunken AW43-88 in Germany, but with missing scan coils. It seems from the data sheets that the Philips AW43-88 scan coils can be used without any issue as the curvatures seem to be very close. In order to fit a new CRT I'll have to remove the support band that goes around the edge of the CRT, and I'm actually a bit terrified thinking of doing that, as I understand it the CRT has no built in implosion protection. Is the purpose of this band to add any protection to the CRT at all or is it just to add holes and standoffs for fixing the CRT to the cabinet? Back in the days, did service technicians need to re-use the band as the CRT was delivered without one?