Category: project

HP 6644A refurbishment – front panel, back protector (#P14F)

Time to finish the HP 6644A revamp!

tl;dr for the last post: Here’s where I stopped refurbishment after cleaning and replacing caps and fan:

First off, those leads stick out quite a bit at the back as well. I can’t really say which diameter I used, judging from the yellow cable lugs these were 4mm² for the power lines and 1.5mm² (red lugs) for the sense lines. Apart from not fitting the old protector, that one already has seen some damage. Probably because it is so tiny…

So: Redesign. Twice, as the first version that closely resembled the original design had really flimsy legs that suffered the very same fate. […]


Failed Philips 46PFL8008S/12 display repair (#P15)

And now for the thing that didn’t make it #100 ;)

A while back, I was donated my second “defective” TV, a 46″ Philips 46PFL8008S/12 with the large ambilight (left/2x top/right with 9 LEDs each). Unlike my first donor which pretty much suffered a direct lightning strike (as described in rant #R2), this one turned on just fine. What’s wrong with it, why would you give away a former 1500€+ device?

(bonus brownie points if you can name the show currently displayed here!)

Well, story is this poor fella cracked a glass table. […]


Post #100 HP 6644A refurbishment (#P14)

Not that anybody cares, but this is actually post number 100 already. I prepared something else that failed (to be reported!), so this one has to do instead ;)

My “lab” power supply situation is ageing and often no longer up to the task, think of LEDs north of 35V or anything that takes more than one amp at voltages that cannot be provided with common computer supplies (3.3V, 5V, 12V, 19/20V) easily. So this is part one of the refresh.

I bought a HP 6644A power supply around six weeks ago off eBay, at 245€ including shipping and rack mounts via best offer. […]


DIY USB and SATA panel mount connectors (#P13)

Next batch of connectors incoming! (yes, I’m onto something)

I bet most of you are familiar with USB panel mount connectors, which (I guess) are a by-product of the slot mounted USB ports of PC mainboards in the late 1990s, early 2000s. Back then, boards had none or few USB ports on their back I/O panel, but often one or two available via pin header. So people obviously needed some slot adapter for them, something like this:

If you slap on a different connector on the other end and omit the metal bracket, this is basically what you get these days when buying USB panel mount connectors. […]


DIY Phoenix VS-PSC style connector (#P12)

Okay okay, “project” is a big word for this. It’s a teeny tiny DIY thing, sparked from MOQ/packaging size worries of a rather unique connector.

In preparation of other things, I wanted access to the data lines of an USB port that is panel mounted. Just tinkerer stuff, you know, seeing if there’s any communication effort happening at all, being able to set current (allowance) sense resistors, you name it. I could have looped all wires to a second/third USB port and made an adapter for it, but that would be a lame one. Instead, I googled for IDC connectors, ideally female to allow easy resistor insertion, which can be panel mounted. […]


Fujitsu P20-2 finalized CCFL to LED conversion (#P9F1)

Canned content, for when I’m busy with stuff that’s not definite yet.

A while back, I tried the CCFL to LED conversion on one of my Fujitsu 20″ monitors. I only had warm white LED strips available at the time, mostly because I no longer require cold white DO STUDY NOW atmosphere at home ;) However piss-yellow doesn’t really shine behind an LCD, so I ordered some cold whites. AliExpress -“2018 New 1m 1200LEDS 2835 SMD LED Strip 24V 1900lm 240LED/M Gold Line LED Ribbon LED Tape Light Cool White Warm White Natura”. 6000K color, 12V, “14-18W”. […]


APC Back-UPS capacity upgrade (#P11F1)

Was that foreseeable? Not sure, but the design called for it…

Now that my modified APC UPS is running smoothly again (#P11), I still had two pairs of these nice XT60 connectors laying around. And as old, to-be-recycled lead acid batteries from UPSes pile up at work, I took one or two of them with me for testing at my electronic load. Like previous batteries, quite a lot of them are really toast, but some of them are in decent condition. Not as in “like new, ready for another year of service in a commercial fire alarm system”, but still holding a significant fraction of their original capacity and delivering a suitable amount of current. […]


APC Back-UPS external battery mod (#P11)

Good thing I’m a doofus. While tidying up cables after some keystone module action, I also moved the bulky power supply of my monitor. And then I noticed that the only thing that absolutely has to be on the battery backup outlets of my UPS unit was in fact…assigned to the surge-protected ones that fail when mains power is gone. D’oh. After some cable identification in that tight space, I moved the UPS around a bit and I discovered a drop of liquid. A very dubious drop at a place where liquid would have to seep through 4 centimeters of a wooden table, or somehow permeate 1.5mm of solid steel against gravity’s pull. […]


Revox Evolution front panel repair (#P10F1)

Soo…the Revox thing from #P10 wasn’t done at the time, and when the missing cable arrived from China (“DB9 Male to Female Gold-plated Extension Cable Pure Copper Line RS232 9 Pin Serial Connector Wire COM Core with Double Shield” for a whopping 4.53€), it didn’t really work as expected.

I wondered: Did they do fancy things with the shielding, in order to squeeze out one more connection from this otherwise 9 pin cable? The cable might have different characteristics compared to the metal-to-metal contact of the serial connectors directly sitting on top of each other. […]


Revox Evolution 19″ panel mount (#P10)

Christmas, the fabulous time of the year where you got plenty of free time, but you aren’t supposed to make hell of a noise :suspect:

Happy 2019, y’all!

Having ordered a second 19″ keystone plate recently, I decided to finally make the user panel of my Revox Evolution stereo system into a front-mount panel that fits the outside of the rack. Without, it got even more hidden inside because of the top-mounting system that is used. Here’s an original marketing wankery image from Revox:

So if that unit is sitting inside of a 19″ rack, imagine the user experience (wank, wank) of operating the display if the top part is blocked by other stuff. […]