[time-nuts] looking for data on time code display

J. Forster jfor at quikus.com
Sun Dec 11 17:25:49 EST 2011

I think I've seen IRIG Time Code SW for the PC that uses a sound card, but
I forget where.  The various IRIG formats are well dovumented.

And yes, Time Code readers were used with high and low speed searches on
IRIG tape recorders. You set Start and Stop points and the tape would
Play, Stop, Reverse, Stop, Play as you demuxed/analyzed the data.

Typically there were 5 or 12 tracks of analog data and two time code
tracks. Sometimes digit was recorded in roughly the same way.



> Fascinating. I also have one of these with slight differences, but it
> does have a Fort Meade tag. Bought it from a guy on the BoatAnchors
> list in Atlanta in the dim past.
> The HTID number is H9823180065821, NSN 664500DISPLAY, User ID STWA104
> The rotary switch adds a 160 KHz position. The two switches are marked
> CODE POLARITY and POWER ON. The rear panel has a 4 pin circular jack
> labeled AUX and a 24 pin rectangular connector marked PARALLEL.
> A partly torn tag taped to the top says Made by TRAK, Model ?? 2234/U,
> SN 517. A plastic envelope contained a DD Form 1348-1A release/receipt
> document from the Defense Reutilization Marketing Office at Meade. It
> released 5 of these units worth $1500 each, dated 1-29-98, ship from
> H98231 (in HTID number above) to SX1213 (marketing office?).
> Somewhere I'd heard that these units were for locating times on tape
> recordings of intercepts. The different filter frequencies are for
> different tape speeds, from high speed search to fine positioning.
> The code might be IRIG but it could just as easily be something the
> NSA invented for the purpose.
> I bought it because I'd visited the NSA museum at Fort Meade and seen
> the code breaking machines. I didn't find them intimidating at all.
> The gift shop would sell me a jacket with NSA logos, but I didn't
> know where I would wear it. There is a certain cachet to having a
> box that was used by top secret agents to decode radio intercepts.
> Bill Hawkins
> P.S. I'd recommend doing some signal tracing from the Input connector.
> We have no idea what signal levels were used, if it wasn't IRIG. I
> never found time to do that.
> -----Original Message-----
> From: ed breya
> Sent: Sunday, December 11, 2011 2:12 PM
> I looked at your first post again and noticed there were apparently
> lots of TTL circuitry, so it could be an IRIG code receiver, and you
> should be able talk to it. If you don't have a source readily
> available, you may be able to fool it into responding a little to
> gibberish applied from a modulated signal generator, just to see if
> it's functional.
> Ed
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