• Get involved.
    We want your input!
    Apply for Membership and join the conversations about everything related to broadcasting.

    After we receive your registration, a moderator will review it. After your registration is approved, you will be permitted to post.
    If you use a disposable or false email address, your registration will be rejected.

    After your membership is approved, please take a minute to tell us a little bit about yourself.
    https://www.radiodiscussions.com/forums/introduce-yourself.1088/

    Thanks in advance and have fun!
    RadioDiscussions Administrators

How to get SMPTE time code from the Domain Controller to the wall clocks..?

S

spinjector

Hi all,

Does anyone know of a cheap & simple SMPTE output device that I can install on our Domain Controller to drive our ESE wall clocks..?

I'm hoping for something dirt-cheap-simple like output through COM1 and some freeware software utility or something.

Thanks.
 
If you have the more recent ESE displays that read ASCII ("U" series), you could write an app to spit out the ASCII string once per second and drive them from your COM1. I don't think your UART will do SMPTE, however...
 
xoanon said:
If you have the more recent ESE displays that read ASCII ("U" series), you could write an app to spit out the ASCII string once per second and drive them from your COM1. I don't think your UART will do SMPTE, however...
Click to expand...

Actually that was one of my first thoughts. I'm pretty good with VB, so it shouldn't be too difficult.

However I was actually hoping for a full SMPTE device, as I'd like to network it to some recording devices, as well.

Also, I was unable to find documentation anywhere on the ASCII-UTC format the clocks use, even in the ESE documentation.
 
Which reminds me - does anyone happen to know what the electrical spec for SMPTE is..?

Is it RS232, RS422, RS485, or something else?

I do know that it's differential, rather than single-ended. And I did see it mentioned somewhere that "it's basically an audio signal", which makes sense, since it's original implementation was to be recorded onto an extra track on reel-to-reel tape machines, whether for audio or video.
 
The units will accept this (format "A"):
9600 Baud, 1 Start, 8 Data, 1 Stop, No Parity

MM-DD-YY <SPACE> <SPACE> DDD:HH:MM:SS <CR>

example: 05-27-10 000:17:59:37<CR>

23 ASCII characters total. The day-of-year (DDD) field can be zeroed, it is not read. Spectracom format 0 or 1 are also accepted.

SMPTE is usually balanced XLR, but in some instances can be unbalanced BNC. Its a slow squarewave audio signal, 25 usec rise/fall, 2 to 4 Vpp usually. Level isn't terribly critical since readers will read the zero crossing.

ESE can build you a converter (ASCII to SMPTE), but it won't be dirt-cheap ;D
 
Status
This thread has been closed due to inactivity. You can create a new thread to discuss this topic.


Back
Top Bottom