Wohler Presto 16x1 Router

Wohler usually has some of the most innovative products on display at the NAB Show, and this year was no exception. Their new Presto video router boasts HD/SD/3G routing capabilities along with real-time video monitoring built-in right on the selector buttons.


The Wohler Presto is a 1RU 16x1 SD/HD/3G/SDI router. with 6 control buttons,, each displaying their respective input signal. These OLED displays measure 0.76-inch diagonally, have an aspect ratio of 4:3, and a 64x48 native resolution. They can display 65,000 colors, and have an estimated life of 30,000 hours.

Wohler’s Presto 16x1 router
The viewing angle is specified at 180 degrees and the switch life is estimated at 3,000,000 cycles.

A green LED above each button lights up when the corresponding source is selected. The chassis weighs about 2.5 pounds and the unit is about 7 inches deep. The back side of the Presto sports the 4-pin power connector, 16 BNC input connectors, two BNC output connectors (with re-clocked signals), and a 3-pin Phoenix plug that provides GPI for the "Dim" and "Lock" features. Power is provided by an external 5 Volt supply. The switcher itself draws about 3 Amps.


As I unpacked the Presto, I couldn't help but think it was a nice change to not have to "piece together" dozens of items before I had a functional unit. Aside from the power adaptor cable, the only other item in the box was the operator's manual (on CD). This was a single nine-page PDF file. The manual was most helpful, reminding me to not block the cooling vents on either side of the unit (which is a good place for them) and informing me that if I did somehow manage to break one of the displays, I should be sure to wipe and clean the residue from any affected skin. (I don't think I want to know why.)

The router is lightweight, but has plenty of heft to reinforce its professional roots. I installed it in my station's high-definition rack, and fed in some HD sources, including NBC primary, and a feed from an HD IRD. I ran the output to an Evertz 2430DAC-HD converter connected to a Viewsonic PC monitor. When I powered up the router, I could see the NBC feed on the first router button, and a sports feed on the second. (The remaining 14 input screens displayed a green raster.) This is normal—no video produces a green raster. According to the manual, if the green raster is too bright for the environment (outside broadcast truck or van, or maybe a dimly lit edit or control room) the GPI port can enable dimming of both the video display buttons and the green selection LEDs. This is accomplished by grounding the "Dim" contact on the GPI port. I decided to try this, using the first thing at hand—a paper clip—to short the "Dim" terminal to ground. The displays did indeed dim a significant amount. While I was around back with the paper clip, I decided to test out the "panel lockout" feature by grounding the "Lock" contact on the GPI port. True to its function, when I had the GPI grounded, I couldn't change my selected source.

Switching sources was about what you would expect with any small router. The buttons have a professional feel and the displays are really neat. The Presto doesn't claim to be a synchronous switcher, but the switches I made were not that offensive, judging from the output video. I decided to try another test to see what would happen if there was a power failure. With sources feeding inputs "1" and "2," with number "2" selected, I pulled the power for five seconds. On powering-up, the input LEDs flashed in sequence for about five seconds as the unit "woke up." After power-up, the Presto defaulted to input 1.

Shortly after I installed the Presto for tests, our main 4x1 "bypass" router died. (We use this switcher to bypass our Chyron Channel Box and NBC Namedropper downstream. I didn't have a spare handy and decided to put the Presto into on-air service. I wired it with input 1 as "normal," input 2 as "bypass Channel Box," input 3 with the "clean MC out" feed, and input 4 designated as "patch in." We ran this way for about a month, with the unit performing almost flawlessly. I found that the power supply runs cool, as does the chassis. Only once did something out of the ordinary happen—input button number "2's" display lost vertical lock. I called the service center and they there told me to hold the button down for about 30 seconds to clear the issue. I tried this and the unit returned to normal and performed flawlessly for the rest of the trial period. According to Wohler, there is a software update to fix this slight glitch. (Later, I discovered the reset procedure in the operation's manual).


The Presto is a solid, slick router. Operation of the unit is simple; however, this little box has a pretty powerful feature set. In cramped environments, (especially OB), having confidence monitor displays on the router's control buttons could free up a lot of space. I would hate to see the unit cluttered up, but selectable audio monitoring (de-embedding) would be a sweet add-on.

Joey Gill is chief engineer at WPSD-TV in Paducah, Ky. and has been with the station for 30 years. He can be contacted at respond2jgill@yahoo.com.