Hi Kurtis, thank you again for your great tips. I have two other LD players (Panasonic LX-V850 and Denon LA-V200G) and they work well without showing the horizontal lines. I use the same composite video cable (Kansai 5C-FB) and the same detachable AC power cord with the same AC socket for the three LD players, only the Pioneer CLD-2750K shows background horizontal lines. The chassis of CLD-2750K is not grounded. Yes I have tried tweaking the tilt pot before and it produces much cleaner pictures after adjustment, though still having horizontal lines problem. Should I replace the capacitor(s) responsible for smoothing out the rectified ac power on the power supply board?
The reason why I've got so many LD players is due to my curiosity. In 1994 I own my first LD Player (Panasonic LX-K550EN) (39W). The picture is very noisy and especially conspicous when the picture background is white. Last year I own a second-hand Panasonic LX-V180EN (32W) (manufactured in 1995). The picture is much cleaner, though the sound too much emphasizes high frequency part (too bright). Then I purchased a second-hand Panasonic LX-V850 (manufactured in 1996). This time the PQ of LX-V850 (42W) is the cleanest of the three, also the blue and green color is solid instead of showing "cross pattern". The sound quality is nice also. Therefore I use LX-V850 for LD recording to a capture card (Compro C100, SAA7134 chip). At that time I have neither Pioneer nor Sony LD players and out of my curiosity I bought the following second-hand players from users of hifi forums in order to compare their PQ with LX-V850:
1. Denon LA-V200G (bought as junk unit)(manufactured in 1997, similar to CLD-D406 without optical output but with VCD playback) - I found the tray cannot be opened. It's a common U1 error and I clean up the loading belt with q-tip and alcohol. The problem is solved. However, only CD's and 8" LD's can be played. For 12" LD's, either the player has problems of searching tracks or the PQ is terrible. I read your suggestions in a forum that the power supply needs recap. I'll do that, thanks!
2. Sony MDP-V90K (bought from a user, claimed as functioning normally) - I found the picture is quite noisy and "digital". I will tweak the tilt pot first to see if there's any improvement.
3. Pioneer CLD-HF9G (bought from a user, claimed as having U1 error) (manufactured in 1995) - I scrub the loading belt and the pulleys with q-tips and alcohol, but U1 still appears. I then buy a packet of 1" (diameter) rubber bands (maybe 500pcs inside) for about 2 bucks. After replacement the player's tray can be opened and it works for CD's. For LD playback I noticed the spindle motor cannot get to the speed or spin for a few seconds and then slow down and spins in the opposite direction. Of course no video comes out. A few days ago when I played an LD, it spins slowly and suddenly I hear a spark and noticed a flash and the unit is off. The fuse is blown. I've checked the power board but the model number is not PWR-1200A, it's VWR-1249A. After I refer to your suggestion in a forum, the arc suppressor (D6) may be shorted and should have its one end clipped. Unfortunately VWR-1249A does not have a D6.
4. Pioneer CLD-D99 (bought from a user, claimed as failure of reading disks) (manufactured in 1996) - The unit shows U2 error. I agree with you that the user has attempted to repair the unit before because when I removed the video board at the top, it found the flexible cables are messy, which should be neatly bundled. Maybe I should suspect bad contact of flexible / ribbon cables, especially the one connecting the mother board and the display panel.
5. Pioneer CLD-95 (bought as a junk unit) - It cannot play LD's at first. Then I played CD's for testing and to my surprise it works. Then I played LD's again and it did play. Is it due to the spindle motor gets stuck due to being idle for years? Is it the case when playing LD's at first, it does not have enough torque to spin up the "stuck" spindle motor but when playing much lighter CD's, it has the enough torque to spin up? The unit has two incidences of generating repeated loud clicking noises. I suspect that is gear clicking noise coming from the moving carriage assembly. I will try lubricating the metal rod and the tooth of the white plastic track with white grease. Unfortunately the PQ is mediocre, maybe I need to adjust the laser alignment first.
According to the above observations, I do not find any problems with Panasonic LD players. Both the power units and the loading belts work great even after 25 years of service. Maybe the former users have replaced the parts before but I bet not. Do you agree that Panasonic uses more durable caps and loading belts than what Pioneer did for LD players?
I have uploaded an LD Karaoke clip (the LD manufactured in 1990, recorded in MPG format) captured using Panasonic LX-V850 with composite output to Compro C100 for your reference (220MB, 3min). It does have video noise but I think it is minimal.
Video link: https://drive.google.com/file/d/1Vyi...BNURGvgdi/view
(Just download it and play in a quality player. The embedded google media player may be not good for playback)