HP8568B和HP8566的模糊格线问题

嗨，我有HP8568B和HP8566A / B，它们都受到模糊格线问题的影响。
即，主要的痕迹是美观，明亮和锐利，但在亮度按钮上的格子“早期出现”，当我的主要痕迹很好，清晰和聚焦时，刻度已经失去焦点。
我知道这是一个常见的问题，许多人说它只是CRT进入老年时期，因为它不能保持长短矢量等的焦点。但有趣的是，格子在较低的强度下看起来很可爱和锐利。
所以我想知道是否有办法改变固件或硬件中的刻度强度。
我可以关闭前面板上的刻度，主迹线保持清晰锐利。
那么有人知道是否有电阻器或微调器设置刻度强度水平？
如果在固件中设置，则可以更改固件以将其关闭一点。
另一件事是，可能有某个组件在某个地方老化并导致格线和主要轨迹之间的这种不平衡。
在此先感谢任何回复:)问候杰里米



     以下为原文

  Hi

I have an HP8568B and a HP8566A/B and they both suffer slightly from the fuzzy graticule problem.
i.e. the main trace is nice and bright and sharp but the graticule 'comes on early' on the brightness button and by the time I have the main trace nice and clear and focussed, the graticule has gone out of focus.

I know this is a common issue and many say it is just the CRT entering old age as it can't maintain focus for long and short vectors etc. But the interesting thing is that the graticule looks lovely and sharp at a lower intensity.

So I'm left wondering if there is a way to alter the graticule intensity in the firmware or the hardware. I can turn OFF the graticule on the front panel and the  
main trace stays clear and sharp.

So does anyone know if there is a resistor or a trimmer that sets the graticule intensity level? If it is set in the firmware then maybe the firmware can be altered to turn it down a bit. The other thing is that maybe there is a component somewhere that ages and causes this imbalance between the graticule and the main trace.

Thanks in advance for any replies :)

Regards
Jeremy