This is in effect a double-post, however I hope that the webmaster will afford me the indulgence of spreading the net a little wider this time.

If anyone has a circuit diagram or service manual for an OEM transflective touch monitor which appears as several brands bearing the generic model CTF840-SC, any clues would be appreciated.

Web search only brings up vendors and operating manual. Screen goes white which was an intermittent problem on one of the other monitors which spontaneously came good after all joints checked and cleaned. Sadly the magic doesn't work on this one.

I should be able to find the OEM but a service manual for what is a use and throwaway product for tour-coach seatback DVD screens, POS/Cash registers, car computers may only be in Chinese if at all.

A luck would have it, an older monitor of the same type which had been becoming cranky finally laid down. A newer monitor ready for the occasion would not power up at all. I have ratted the gizzards out of an even older monitor of the same series to get two going but would like to troubleshoot the newest one.

Collectively, all three work but component substitution introduces a bad screen-mapping problem on any two, a real conundrum.

Why three? The SI2K fullbodied camera can daisychain several on board for camera op, focus puller and I also used the non-modified monitor on the EX1.

I can go and get a POS/cash-register monitor easily enough but would like to try to fix this first.

I managed to sort the erratic touch monitor. In one older version, there are two conductive areas on a flexible PCB which achieve contact with the metal panel via two fine mesh pads which are intended to maintain reliable contact via very many points of contact.

Contact was being broken by normal touch inputs or flex of the casework on the Noga arm when being re-positioned. A small block of lens-case black foam between this PCB and the rear case half seems to have fixed it for now.

The second monitor ended up having a ribbon cable damaged by being trapped between the screw pillars of two case halves and a screw going through it. The ribbon cannot be repaired. Even hard folds will make them malfunction. Fortunately, the touch panels with their ribbon can still be had from the vendor in Germany. They are now obsolete and apparently out of stock with the OEM in Taiwan. The little controller board remains available.

Some later model replacement panels may need an updated driver to be installed. This is a strange two-stage process with the P+S Recorder unit but otherwise trouble-free.

Pulling these monitors apart is a "real mission" as Kiwi filmie Chris Soucy says. If anyone needs to mine inside one, feel free to ask how. There are a few traps.

There is a newer model in this monitor series, the CTF846. The LCD screen is apparently backlit by LEDs versus the mini tubes top and bottom in the older series. This requires the touch driver to be updated. I have not yet investigated whether the P+S split box on the back can be changed over by simple unplug and swap. The fixtures in the casework seem the same.

Most operators using the SI2K as a tethered camera will likely be using touch monitors other than the P+S modified CTR840-SH or using the controller on their laptop or other portable device.

For those using the P+S Technik full camera-recorder system and their touch monitor has done a die, there has been a successor for the CTR840-SH, the CTR846.

It is very similar in appearance, function and layout and is vended by CarTFT in Germany. I believe there may be an OEM version available in Asia but thus far I have not been able to track it down. The mounting points on the rear of the case are identical to the CTR840-SH.

I have tested one with the SI2K. It requires the updated driver to be installed. It otherwise behaves identically.

The kit comes with a fitted breakout lead for in-vehicle installation. I have not yet checked to see if the internal connectors are the same. If so, it may be entirely possible to conveniently exchange from the CTR840-SC, the entire rear case panel plus P+S breakout box with cable attached as a complete assembly.

However, to get the rear cover off, the P+S Technik breakout box has to be dismantled to be removed to gain access to a rear cover screw which is concealed beneath a central mounting plate.

The new screen is back illuminated by LED compared to the mini discharge tubes of the older monitor.

The display is crisper and colours seem brighter and more faithful. The very fine text in the status field along the upper edge of the DVR interface appear to merge and require a little more effort to read.

Like the original monitor, the screen is transflective. Viewing outdoors in direct sun remains a challenge requiring a deep hood over the screen.