Yet, another job related to the 3562A, same machine that also had the ROM board defect. This unit also has a weak display, and I have been asked to check replacement-repair options.
After a brief search, there aren’t any spare CRTs around, for the 1345A display used in the 3562A. The last good ones might have been purchased-stockpiled some years ago, by corporation that need to keep equipment going.
Well, fair enough. Luckily, failed CRTs and their limitations are a common feature of dated test equipment. So other have already invested time and effort to provide a solution: the LCD retrofit.
Why not just replace the whole instrument, with something new, up-tp-date, and more manageable? Several reasons:
(1) Many clients have proprietary-custom software running certain automated tests, using certain types and specs of test equipment. The final product specs have often been agreed upon with the OEM, in contracts that are a big hazzle to change. Some of these products, in fact, most, have long service life, so the test rig needs to be kept alive, more or less, at any cost.
(2) Cost – well, new test gear of the proper kind is outrageously expensive. Not taking about plain stuff here, but powerful equipment, network analyzers, spectrum analyzers.
(3) Servicabilty: talking about smaller businesses, not big corporation, often it is quite handy to stick with somewhat dated analyzers etc, because they are perfectly up for the task, the operators are trained, both in using and serviceing them, and often, spare units-parts units are around and can be procured at a fraction of the cost of repair of new equipment.
(4) Quality. Arguably, and except for new digital signal-fast scope stuff, the instruments build in the late 80s and early 90s might be the best ever build. Most of them have specs and typical performance far above what most regular quality can provide nowadays. The reason is simple, in the 80s, these rigs were build for the military and related agencies as the key target market. Nowadays, for consumer electronics, consumer communications… One exemple: the HP 8566B spectrum analyzer. Not sure about the price of such equipment nowadays, if build new – certainly 6 digits. On xbay, they go for about few cents per USD list 1985 list price… and be assured, no big deal to get them working in-spec.
The LCD replacement kits have come down in price considerably – earlier on, still USD 1000+, now, check this out:
USD 400. Not bad. This includes display. LVDS driver. And certainly, the controller board, to adapt the display to the 3562A.
Here, from the inside:
The display: it’s a rather dated SHARP LCD DISPLAY, LQ057V3DG02, TFT 5.7″, 640×480. But rather then stockpiling CRTs, I now have a few of these in stock now – found them for about 15 EUR each surplus – this will allow service of the LCD-retrofit units, for years to come, without any need for modification to fit another type of LCD display…
I can tell you, such retrofit is worth every dollar. If you have any of the CRT analyzer with the screen gettin dimmer. Don’t hurt your eyes.
A quick glance at it – it’s great to work with it – color display, rather than dim green display.
The color settings work fine for the most part – there are some little bugs in the NewScope-5, related to the text color, in some menues (first character has different color). However, this has really no impact on the great advantage of such LCD retrofit.