Tektronix DC50x Timer module plug-in

[Jester]

Recently I had to verify the timing of some long period timers (1 hour).  For next time I'm considering picking up one of the Tektronix plugin timer modules (DC501, etc) assuming they can time for long periods.

The Barytech site shows (10 second count), however when I look at the specificaions for the DC503A, it shows 100ns to 10^9
I realize there are various modules and perhaps some can't measure long times.  Can anyone with a DC50x series timer comment as to time duration capabilities?

Also can a "A" series module for example a DC504A be plugged into a non A series chassis for example a TM303?

[alm]

According to the Tektronix 1982 catalog the DC503A can measure single shot periods up to 10⁹ s with 10⁸ steps of resolution. Same with Time A -> B. So sounds to me like it should easily to 1h periods with a resolution of 100 µs. I do not have one myself to check.

The A suffix does not matter for mainframe compatibility. Any DC5xx counter should work in any TM500 mainframe. The only exception is anything in the 5000 range. The DC5009, for example, would need a TM5000-series mainframe. Although some plugins can be modified to work on TM500 series mainframe.

[Jester]

Thanks for that. The specifications for the other timers (DC501 etc) don't specify a maximum time, so it's not clear if they can do long times, it might be that the DC503A is the only one capable, but I'm not sure?

[MarkL]

I have a 503A.

In timing mode it has 8 digits of count that is clocked from 100ns to 10sec in 10x steps.

So, using a clock of 100us, as alm says, it can count up to 9999.9999 seconds.

It also has an overflow indicator, so if you know your value is within a particular range, you could use an even higher clock rate for more precision and let it overflow.

[alm]

The DC501 only does frequency or totalize, so will not measure time without external oscillator. Obviously you could feed it a 1 kHz signal and use totalize, but you would need to use the rear terminal connectors to start / stop it. See the Tektronix Catalog from 1977 for more information.

[MarkL]

If you decide to get a DC503A, try to get one with the ovenized oscillator, aka. "Option 1".  The sellers sometimes don't mention option 1 in the listing even if it has it, but you can see the large oscillator can from the back.  See photo below.

I think I paid $40 for mine.

[Jester]

If you decide to get a DC503A, try to get one with the ovenized oscillator, aka. "Option 1".  The sellers sometimes don't mention option 1 in the listing even if it has it, but you can see the large oscillator can from the back.  See photo below.

I think I paid $40 for mine.

I will keep my eyes open for the ovenized oscillator, seems like a good deal at $40.

The DC504, DC505 and DC505A are also described as a counter/ TIMER, while the non A DC503 is decribed as a Universal Counter with out the / TIMER designation, although the plain 503 does have a Time A-B and Time manual selection, they might? only count to 10 seconds (I'm not sure)

Summary:
DC503 7 digit (9999999) Good
DC503a 8 digit  (9999.9999) GOOD  

DC504  5 digit, so 999.99 seconds (16 min) max   NO good
DC504A is 6 digits, (not specified, might only go to 999.999?)

DC505 7 digit (not specified, might only go to 10 seconds?)
DC505a 7 digit (not specified, might only go to 10 seconds)?

DC509 8 digit Reciprocal  (10980) GOOD   Can't find online manual

[MarkL]

I don't have a DC503, but from what I'm reading in the user/service manual it does have a timer function from A trigger to B trigger (plus manual), as you say.

Differences from the DC503A include only 7 digits instead of 8, and a lesser timer clock rate range from 1us to 1sec.  The DC503A also has a slightly higher input frequency of >=125MHz, but this doesn't matter if you're trying to time on the order of an hour.

I'm not sure what you want to time on your input signal from what to what, but if you were using a DC503 you could split your signal with a T and send it to the A and B inputs and set the triggers appropriately.  You could set them to the same slope to time a whole cycle, or to different slopes if you wanted to measure the time high or low.

You would then select a clock rate of 1ms, which would give a maximum count of 9999.999 seconds.

DC503 user/service manual:

  http://w140.com/tekwiki/wiki/DC503

The manuals for the other counter/timers you mention are here:

  http://w140.com/tekwiki/wiki/TM500_and_TM5000_plug-ins

[Jester]

I picked up a DC503 at a local surplus shop. They had several to choose from, picked the best looking one with the option 1 (better oscillator). It does do long time measurements in Time A-B mode however the time does not update on the display until after the event occurs, that's fine when measuring short pulses, however I want to use this for minutes to hours. So I tweaked the logic a bit and it now updates the display in real time. So I now have a handy dandy mutipurpose timer.

Thanks to those that replied with advice:-)

Worlds most boring action video.... http://www.filedropper.com/timer_7

After a hour......

I just need to figure out how to squeeze in the miniture toggle switch required for this mode onto the limited front panel space

[MarkL]

Nice mod on the display.

If you don't switch between modes frequently and you don't really want to drill out the front panel, you could mount a switch that's accessible from the back.  The DC503A uses a 0.1" pin jumper in the back that selects between the Totalize A and Manual Timer, so it's not unheard of.

[texaspyro]

You could grab a $200 TAPR TICC dual channel time stamping time interval counter.  It has around 60 ps resolution and can measure time intervals from around 100 ps up to 2^32 seconds.  It does require a 10 MHz reference clock.  It is currently limited to around 100 measurements per second but the goal is to reach 1000 / second on each channel.

https://www.tapr.org/kits_ticc.html