Busy Summer 2016

image of two racks We have another extremely busy summer this year with 10 systems under construction in-house, and more in the planning stage for installation later this year.

Here are two out of the 10 racks under assembly by my associate Dan M.
Two additional racks are already complete and undergoing final testing prior to classroom deployment.
Our deadline for all 10 is September 1st.

cleanrack

Dan is also CTS Certified and does extremely tidy and serviceable rack layout according to industry standards.

With the exception of the system controller, all of these systems are now designed around Atlona core products.

stacks of boxes

 

 

 

 

 

More later. Cheers.  -Pete

RF remotes for camera presets

As posted previously, the IR triggers for camera presets were a fail due to false triggering. I wanted to provide manual pushbuttons at the three, main locations to allow the users to manually control presets. The issue which caused us to go down this road was this: no available pathway from stage-right to stage left for any type of low-voltage wiring. I wanted to try RF remotes.

I found a great DIY Build site called adafruit which stocks numerous RF transmitter and receiver modules. I selected a little 4-channel receiver board, and a compatible 2-button (2-channel) transmitter keyfob. This would allow me two wireless pushbuttons.

I needed to add a few external components (relays, driver transistors) to the receiver board, so I found some surplus perfboard and parts and soldered it all together. RF-board

The little receiver board is about half the size of a business card and is seen on-edge in the photo here:

For the transmitters, I disassembled two of the keyfobs. The batteries take up most of one side of the circuit board.

Fob2  Fob4

On the reverse side, under the mechanical dome buttons, are the contacts to which I soldered a pair of wires to extend to a hardware-store doorbell button.

Fob3  doorbell

I mounted the doorbell to one side of a single-gang wall plate with the wires extending through a small hole, then used — gaffer’s tape — to attach the small circuit board to the rear of the plate. I mounted the plates to shallow junction boxes at my two remote locations.

I found a surplus power supply and gutted the case. It was a perfect size to mount the receiver with the rest of our AV gear and the Vaddio camera controller.

Case1  Case2

I wired the receiver to the Vaddio controller and the remotes work perfectly! The whole mess cost less than $25.  -Pete

Cheap IR Triggers, Part-3

Good news: The triggers worked! Bad news: We tried the IR triggers for a couple of quarters and found it too difficult to narrow the window to directly in front of the whiteboard.

The IR triggers were subject to reflections off of the surface of the whiteboard; student movement in the front row would cause a trigger and unwanted camera movement. After many complaints, the IR system was scrapped and replaced with a manual, RF trigger system. And it has been working great. More later.

 

Cheap IR Triggers, Part-2

IR sensor plateAs our summer installations progress, I have had more time to consider where the IR triggers for our Vaddio camera systems will be installed. One is wall mounted, the rest are on the ceiling above the whiteboards. I wanted the ability to vary the coverage angle, but the heat shrink solution, mentioned previously, was too cheesy.

I decided on using the shell of a surplus Switchcraft D3M connector with the sensor mounted recessed into the rear of the shell–a perfect fit.

IMG_3424 (Medium)

 

I hot glued the circuit board onto the rear of the faceplate (and my finger. OWW!).

For now, I am just going to tape the little sensor board onto the rear of the connector shell until I have finalized the coverage angle to mitigate false triggers.

Parts cost is still under $10.

Cheaper IR Solution

We have been installing nice Vaddio HD-19 cameras in our classrooms to enlarge lecturer’s whiteboard scribbles onto the large projected image. Our first outings with these cameras included Vaddio’s HotShot preset controller as well as those heavy rubber trigger mats placed in front of the whiteboards and podium. The mats don’t work well with a chair sitting on top of them (!), so ceiling-mounted IR sensors should work great. Vaddio wants hundreds of dollars EACH for their IR triggers, so I decided to make our own, for under $10. each.

IR sensorMy intent was to find a sensor which could be mounted behind a single-gang wall plate. I found these little sensors ‘with relay’ on eBay for about $6. each, so we bought eight of them. The turn-off delay is adjustable.

In initial testing I found that the relay output is not ‘dry,’ but is +12Vdc. That’s not compatible with the input to the HotShot controller, so I traced out the circuit to see what could be done.

cut-trace

I located a trace which can be cut to remove the Vcc from the relay output, and lifted a little chunk of copper from the board with an x-acto knife.

I just added a short jumper wire to the relay contact and now I have my dry contacts: jumper wire

 

 

The next step is to add a small, 4-contact barrier strip of some kind.

We always have parts drawers full of leftover hardware, and I found a handful of small connectors from some Extron project.

I super-glued the connectors onto the end of the little relay. Super glued

These will make a perfect barrier strip. The next step is to trim and terminate the four wires:

wired

 

 

 

 

 

This first board is my prototype. I drilled out a single-gang faceplate and hot-glued the IR sensor and relay board to the back of the faceplate. faceplate-rear

 

The blue outline is the opening into the Wiremold  2400-series junction box I expect to be using. The whole wretched mess has to fit within that rectangle.

And it does:

IMG_2972 (Large)

 

 

The PIR sensor has a wider angle than desired, so I need to experiment with various tubing, heat-shink, etc. to narrow the vision range.

In this case, black 1/2″ heat shrink works, but it’s unattractive and more difficult to fine-tune. I’ll post additional images as the project continues later this summer.

Heat shrink

I have tested the board and it works great with the controller.

Poor ‘Best Practices’

old room layout

Before

Today I had a chance to dig around inside a large Crestron DM installation which was performed here just a couple of years ago. The department owners/users have had significant problems with the installation ever since the job was completed. Unfortunately, due to politics, my own department and I were never consulted and we were unaware of the project’s scope until after the installers were on site. The installation was performed by a large and well-known design-build firm. The owners/users are generally happy, but there are random failures and at the moment all audio has died, prompting the request for my consult. The owners were never provided as-built drawings. This is a full DM matrix with support for video conferencing and multiple displays.

Panorama

I spy some significant installation errors and poor practices. What do you think? The system is in two parts: a lecturer’s console with rack, and a full-size distribution rack in a nearby closet.

Instructor's view of consoleThe console casework is nice, but the rack is barely large enough to support all of the hardware needed for the front-end of the system. The desk is height-adjustable, electrically; but is not used since stuff stops working whenever the desk is raised (see below).

It wasn’t until after the system was in operation that the users discovered there was not appropriate horizontal real estate for laptop users. DOH!

Console rack frontThe console rack is 15-RU and four of the spaces are taken up by horizontal power strips. There is room in the rear of the rack for vertical strips which could have possibly allowed tidier cable dressing between hardware and a traditional cable dump at the bottom.

C-Rackrear

This is a mess.

There are a number of jumper cables which are too long, so they are coiled up and hung from self-adhesive tabs(!) Several of the tabs have failed (they all do, in time), causing the weight of the cables to put stress on the connectors and cause random disconnects–particularly any wretched HDMI connectors.

Inside console rack

Here is a look up inside of the rack.

Standard plastic cable ties are used on all cables including category and DM.

It is not so obvious in these images, but power cables are often seen cable-tied to signal cables–very poor practice and definitely contrary to the contract specs. Nobody called them on it.

 

Under the desk proper, things could have been dressed better, and cables with generous service loops bundled more securely to allow for the desk height adjustment without stretching cables and connectors like a bow string. I can see how raising the desk will cause failure.  Under-desk wiring

The main distribution rack is located in a very small closet behind the whiteboards:

Distribution rack

The rack has to be on casters to rotate for access in this tiny space. In this image it is turned for access to the rear of the rack.

I seem to recall the wall-mounted air conditioner was added after-the-fact to mitigate overheating.

At first view the in-rack wiring looks quite tidy!

 

Let’s look more closely. Rack rear

 

 

 

It appears that power cables are on the left, and signal cables are on the right. Excellent.

Hmmm. I don’t see any Velcro straps used on the category cables yet. Are those cable ties really as tight as they appear?

IMG_0846 (Large)

Here again, power cables are tied alongside the DM, audio and LAN cables. No Velcro ties.

Connector farm

 

 

 

Shielded, twisted-pair cables are nicely terminated and labeled, but no cable ties were used to secure the cable to the connector.

Cable ties

This is beneath the Ethernet switch. Category cable cinched down with cable ties alongside the power cables.

Along the side of the rack, there are bundles of power and signal cables kinked together:

kinked cables

 

I will have a look around again later. The owners have asked the installers to return and repair the intermittent problems, as well as to provide the as-built drawings the original contract required. The system is “out of warranty” so time-and-materials charges apply. What do you think? Would you ever use these installers?

Busy Summer 2014

This will be fun. It looks like we are going to have a VERY busy summer installation season! This is the pile of equipment being staged for just two large lecture rooms. Now, we need to hire qualified installers.

Boxes and boxes

I Really Want To Like These, but… – Part 1

One of the great parts of my job is to be able to evaluate many brands and products; and if some odd product(s) meet our requirements they may get specified for an installation–even if the manufacturer is not well known. For example, in the last year we have used a number of HDMI extenders and matrix switchers from RTcom with generally good results. More about that another time.

Recently we needed a couple of HDbaseT distribution amplifiers which would specifically pass RS-232 through the receivers to the displays (one-way). This is for an interesting new computer lab in the Library. At the time we were doing the system design, the only model I could find with that claim is from a company called Apantac. I spoke with the folks in sales, who confirmed that their DA does indeed pass RS-232 (This had previously been a failure with the early HDMI extenders we purchased from Atlona). There is also an integrated LAN port, but perhaps it is only used for configuring the RS-232, yes?

DA-rear, wideApantac ReceiverSo, as soon as the two Apantac DA’s and receivers arrived, we put them on the bench. The actual hardware appears to be very well constructed and feels solid with significantly better finish than the RTcom.The exhaust fan is somewhat louder than expected, but no louder than in the Extron matrix we installed last year.

But–wait–where is the manual?

  • FAIL: NO User Manual or other documentation whatsoever. There is none available on the Apantac product website, either. This was a huge oversight on my part, as I usually download all pertinent install manuals for study during the design process. Gah.

OK, the connectors are all well-labeled, so testing shouldn’t be difficult. RS-232 is only two conductors plus a ground, so we have a better-than-50% chance of getting it right the first time. But there was no combination of pins 2 & 3, or baud rate which would pass a signal. I started making phone calls.

  • FAIL: No RS-232 pass-through. The specifications and product literature claim it, and the Regional Sales Manager had confirmed it prior to the order being placed. It took a number of phone calls to Apantac’s tech support before they confirmed with the factory in Taiwan that the RS-232 pass-through does not work, nor can it be made to work. This is blatant false advertising. My associate here was also told by the support technician that the LAN port/webserver does nothing.

Apantac DA insideDuring bench testing, I was curious what was inside the box and also to investigate why is the exhaust fan so loud. There is no ‘Warranty void if…’ sticker on the lid, so I removed a few screws for a look inside. The inside assembly is very tidy, and the large DC fan is just plain loud. There is another small whizzy fan in the center, pointed at a chip with heatsink.

Hmmm. The power supply is missing a ground terminal. Then where does the electrical … ground… go? Uh oh.Apantac power supply fail

  • FAIL: The electrical ground wire is coiled up in a ferrite ring and hanging in space; you can see it in the image above. An air-gap ground? Is this legal to sell? Did it meet UL approval? Do I dare connect it to the power supply?

Apantac Floating ground fail

 

 

 

I have no confidence that the Apantac Tech Support will know what to do with it.

DA-rear

Beneath the electrical mains socket is the mystery dipswitch board (top) and beneath it appears to be a populated webserver card (bottom).

So what do we do? We paid $2,400. each for the two DA’s, plus $215. each for 14 HDBT receivers. The installation is scheduled to begin in a couple of weeks and I just do not have the energy at the moment to send the whole wretched mess back and shop another HDBaseT DA and receivers from some other manufacturer.

On the surface, Apantac appears to have a great product line. But after this sales and support failure we will never touch this brand again. Just my considered opinion.  -Pete