Month: August 2019

Hexem E-I-R Meter: Angry Battery Salad

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I was at Surplus Stuff and they had two of these Hexem E-I-R meters. They’re beautiful multimeters that were introduced by Belleville-Hexem of Los Gatos, California around 1958.

Los Gatos? That’s me! Prrrrrp!

Google it if you wish but you’ll only find tiny blurbs where it was advertised in a few trade magazines from 1958-1960, and it was recommended by Systron-Donner to calibrate an early chopper stabilized instrumentation amplifier.

Hexem also advertised an “incremental” meter that sounds in concept like a differential voltmeter. This one’s interesting in that it can measure some very high resistances.


And now, we take out two screws in the back and go to look for what batteries it needs. I’m guessing maybe a D and a B (45 volt). Okay, the beautifully built steel case comes apart aaaaaaand

What have I done?!

I’m questioning some of my choices in life about now

There are more battery holders hidden under the shield here?!

Ok, so breaking it down… The RM1R is a 1.34 or 1.5v cell, kinda a 1/3 AA or so. I say 1.34 or 1.5 because I’m unsure if it was supposed to be mercury or alkaline.

Mercury batteries were common in measurement applications through the 1960s as they provided good life and very stable voltage over their lifespan. Of course, they create an toxic ecological disaster and have fallen from use. They’re common in early camera light meters, in which case they can be directly substituted for a zinc-air hearing aid battery with no recalibration required (the change in reading is less than 1/3 f/ stop, which is less than the adjustment steps on any film camera I’ve ever seen!)

The two batteries down in the weird saddle holder would have definitely been LARGE 1.34v mercury cells.

Meanwhile the two common ones are the D cell and the 9v at upper right. Yes I checked the cross reference. The tall cylindrical cells are 6v and N are small alkalines.

This is ridiculous and beautiful and I’m not sure if I’m going to bother acquiring several pounds of uncommon batteries to use it. Uhhhhhhh

/!\ DANGER: THIS POST CONTAINS COMIC SANS /!\

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This dumb thing has never once inspired any confidence in me, between the choice of font on its GUI (various old Harris / Leitch products are infected with Comic Sans including whatever this was based on) and the fact that it ROUTINELY makes one of our stations fail to black and has to be bypassed out brutally with a patch cable and whacked in the face with a large trout with great vigor until it reboots. As an added bonus, the setup / diagnostic screens do not work, you instead get a big fat flash of “Not Available” in Comic Sans.

 

this inspires about as much confidence as it should (none at all)

also wordpress literally reverted automatically to the default style and will not allow me to type more than one block of text in Comic Sans and this is probably very much for the better ok

At least the actual keyer card (as unstable as it is) presents a tiny bit of data via a… perplexing, tiny, graphic VFD display on the module edge. Why a VFD here? At least it’s not an OLED that goes unreadable after a year.

ok that’s enough comic sans now i’m gonna go wash my eyes out with tape head cleaner

 

dasHECK

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Original image from @2clouddogs

The Monroe Systems / Digital Alert Systems DASDEC is a special sort of wonderfully awful. I mean, it takes the usually wonderfully awful state of existence that is any part of the flawed-ass Emergency Alert System and adds its own layer of questionable toppings. It’s an overly complex Linux based PC with a web interface that looks like something I would have hacked together on an old junked PC barely chugging along with Linux on it in my parents’ living room in 1999, and it’s theoretically “compatible” with a couple of different flavors of video/audio keyers used in TV airchains for inserting text crawls and audio, but that works about as reliably as asking a shoobcloud with selective hearing something other than “would you like to go on a walk”?

I’ve heard of them working just fine and dandy in radio stations where they’re part of a far simpler setup, ie, not a setup dependent on poorly written and tested software (internal to the DASDEC) communicating on poorly written and tested software (yes, yes, I am indeed referring to Evertz keyer firmware, what ELSE would I be talking about here?).

A day in the life. We had to jump through hoops to ensure the thing would successfully air the national test, and it did, but we had to add distribution amps and other things that we shouldn’t have had to add because we had the Monroe “multi player” and I don’t even want to think about this anymore.

I’ll be over here thinking happy thoughts about cloud dogs.

The best testimonial I’ve ever seen

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From a fellow engineer:

Our guys were so impressed with the Selenio at our sister station that as the NetVX aged into backup status, we bought a Harmonic.

selenio shitpost
sorry, I only have M$ Paint on this workstation and it’s fairly useless for proper shitposting

 

For the uninitiated— what this unit does in its most common configuration in a TV station is it takes in one or more audio/video inputs, encodes them to MPEG-2 program streams for digital television, and finally sends the output out as an ASI stream. An ASI stream is a combined feed of all of the subchannels to be sent over the air plus the metadata (PSIP), and is what is actually modulated and sent out by the transmitter. The PSIP is used as an index by your receiver and populates both the channel definitions and the program/station info that gets displayed in the program guide. That being said, it is the house of cards upon which your entire station is delicately balanced. 😉

In all seriousness, this is one of the strangest, most fragile, and most inherently unsupportable pieces of hardware I’ve ever worked with. The UI from which you have to perform most configuration tasks is based on Microsoft Silverlight, which is a dead-ass format M$ came up with to compete with Flash, which is also a dead-ass format. Double-dead-ass? I dunno. It’s pretty awful and soon I predict that’ll require us to keep some old computer around with an EoL version of Windows and Silverlight installed and no auto updates allowed because M$ will just decide to flush Silverlight away entirely.

There’s also a telnet interface into the thing for which there’s little documentation. Certain configuration tasks (which is to say most of them) require a call in to Imagine Communications support because it’s just… well, at least one person who worked on the software knows how it works, right?

The hardware design is kinda questionable and the firmware hocks up hairballs for no good reason. So far across the three of these I’ve worked with, I’ve experienced phantom frame controller failures, A/V desync, audio loss, video loss, video freeze, video macroblocking, unreported loss of ASI output with invalid picture input, reported loss of ASI output with valid inputs, and one that just plain powered off and restarted during the evening news. Oh, and you see that little display on the front? It CAN display useful status information, but…. doesn’t. Also, Imagine Communications’ idea of a “screen saver” for the little OLED screen is to display “Imagine Communications” on the top line, unmoving, forever… so when you try to view any status/fault info, you’re reading it through a permanent shadow of “Imagine Communications” that’s practically CHISELED into the matrix. Ew.