Sunday, 29 April 2012

Black Matrix tubes all the way

Today I upgraded my modified Blaupunkt IS 70-33 VTN with a Black Matrix Philips tube. Everything went according to plan (swapped yoke, aligned image, adjusted Focus and Screen controls, etc.) and the end result is very nice indeed!

This TV only has two niggles. There is a very slight "shimmering" in the bottom left corner. Most Grundig TVs I've tried exhibit this problem. Also, the corners aren't as sharp focus as some of the Loewes and Sonys I've seen. If those two issues weren't present, I'd end this ongoing SCART hunt right now. It looks that good!

Analogue chassis, black matrix tube, native resolution & refresh rate. Lovely!

In other news, I ditched a car load of parts today. Now that I figured out how to upgrade my analogue Grundig boards to the Black Matrix tubes, a whole bunch of stuff that I've hung onto "just in case" really didn't seem necessary any more.

Totally spent after lifting a pile of 26 inch tubes down the stairs, into the car and then into the ditch at the rubbish dump. Phew! Almost time to sit back an enjoy playing some games, I reckon...

Tubes, degauss coils, sawn up cases... ugh!


  1. Good to get rid of all the spare gear after getting closer to finding the best solution. Sounds like youve settled on the type of picture tube needed. Is it now a matter of finding the right analogue chassis to suit?

  2. Yep! So, the check list so far:

    * Newer Black Matrix tube
    * Older analogue chassis
    * Analogue controls including: V-size, V-position, H-size, H-position, Pincushion, Trapezium
    * Ability to sync to any frequency between 50 and 60 Hz
    * Ability to display at least 256 vertical lines

    So, that narrows things down quite a bit! From here, it's all about other performance aspects such as focus, convergence and image stability. My current setup is great for everything except focus and image stability. I'm guessing focus could be improved with a brand new flyback and fresh capacitors. Certainly not the tube causing lack of focus in the corners (tested with a Loewe chassis). Not so sure about image stability. Perhaps capacitors in the line filtering? We'll see...

    I need to explore my Sony AE-1 chassis. That has all of the above and more. The only downsides I see are the Trinitron tube (looks less "classic" to me) and possibly the convergence (although it's a standard setup with convergence rings rather than the moulded yoke type that the Philips uses.)

  3. Nice blog read. The 'slight "shimmering"' (shaky raster frame) you mention will be the capacitors (as you've stated) on the LOPT.

    Perhaps make a note of the larger values and go hunting for replacements at that local waste dump - save a couple of bucks ;-)

    Be sure to discharge them prior to removing. ((@_@))

  4. Thanks for the advice! I'm gonna try to look into this at some stage. Cheers!