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HP5328B TI avg showing half value

MD
Magnus Danielson
Tue, Apr 18, 2023 10:32 AM

Fellow time-nuts,

As I was testing a HP5328B in TI avg mode, it displays about half the
value expected. I pulled out a SR620 to verify the proper time-delay.

I'll pick up my HP5328A with option 040 and check that one.

While I will dig into this, maybe someone remembers seeing this.

I'm not ruling out handling error or hardware error, but for the moment
the signal seems OK at least.

Cheers,
Magnus

Fellow time-nuts, As I was testing a HP5328B in TI avg mode, it displays about half the value expected. I pulled out a SR620 to verify the proper time-delay. I'll pick up my HP5328A with option 040 and check that one. While I will dig into this, maybe someone remembers seeing this. I'm not ruling out handling error or hardware error, but for the moment the signal seems OK at least. Cheers, Magnus
BC
Bob Camp
Tue, Apr 18, 2023 2:36 PM

Hi

How big a delay are you looking at?

Bob

On Apr 18, 2023, at 6:32 AM, Magnus Danielson via time-nuts time-nuts@lists.febo.com wrote:

Fellow time-nuts,

As I was testing a HP5328B in TI avg mode, it displays about half the value expected. I pulled out a SR620 to verify the proper time-delay.

I'll pick up my HP5328A with option 040 and check that one.

While I will dig into this, maybe someone remembers seeing this.

I'm not ruling out handling error or hardware error, but for the moment the signal seems OK at least.

Cheers,
Magnus


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Hi How big a delay are you looking at? Bob > On Apr 18, 2023, at 6:32 AM, Magnus Danielson via time-nuts <time-nuts@lists.febo.com> wrote: > > Fellow time-nuts, > > As I was testing a HP5328B in TI avg mode, it displays about half the value expected. I pulled out a SR620 to verify the proper time-delay. > > I'll pick up my HP5328A with option 040 and check that one. > > While I will dig into this, maybe someone remembers seeing this. > > I'm not ruling out handling error or hardware error, but for the moment the signal seems OK at least. > > Cheers, > Magnus > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe send an email to time-nuts-leave@lists.febo.com
MD
Magnus Danielson
Tue, Apr 18, 2023 3:02 PM

Hi,

So I fiddle around at 100-400 ns and readout turns out linearly at about
half value.

The frequency is 100 kHz of the pulses, which can be tweaked, but for
the moment fits is purpose.

Now, turns out that using manual setting of trigger-offset rather than
auto removes the issue. I've not concluded exactly why, but it does.
Will grabb the other 5328 to see if it does about the same.

Maybe I need to trim up the input side?

For reference, using TTL signal levels for this, terminate with 50 Ohm.

Cheers,
Magnus

On 2023-04-18 16:36, Bob Camp wrote:

Hi

How big a delay are you looking at?

Bob

On Apr 18, 2023, at 6:32 AM, Magnus Danielson via time-nuts time-nuts@lists.febo.com wrote:

Fellow time-nuts,

As I was testing a HP5328B in TI avg mode, it displays about half the value expected. I pulled out a SR620 to verify the proper time-delay.

I'll pick up my HP5328A with option 040 and check that one.

While I will dig into this, maybe someone remembers seeing this.

I'm not ruling out handling error or hardware error, but for the moment the signal seems OK at least.

Cheers,
Magnus


time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe send an email to time-nuts-leave@lists.febo.com

Hi, So I fiddle around at 100-400 ns and readout turns out linearly at about half value. The frequency is 100 kHz of the pulses, which can be tweaked, but for the moment fits is purpose. Now, turns out that using manual setting of trigger-offset rather than auto removes the issue. I've not concluded exactly why, but it does. Will grabb the other 5328 to see if it does about the same. Maybe I need to trim up the input side? For reference, using TTL signal levels for this, terminate with 50 Ohm. Cheers, Magnus On 2023-04-18 16:36, Bob Camp wrote: > Hi > > How big a delay are you looking at? > > Bob > >> On Apr 18, 2023, at 6:32 AM, Magnus Danielson via time-nuts <time-nuts@lists.febo.com> wrote: >> >> Fellow time-nuts, >> >> As I was testing a HP5328B in TI avg mode, it displays about half the value expected. I pulled out a SR620 to verify the proper time-delay. >> >> I'll pick up my HP5328A with option 040 and check that one. >> >> While I will dig into this, maybe someone remembers seeing this. >> >> I'm not ruling out handling error or hardware error, but for the moment the signal seems OK at least. >> >> Cheers, >> Magnus >> _______________________________________________ >> time-nuts mailing list -- time-nuts@lists.febo.com >> To unsubscribe send an email to time-nuts-leave@lists.febo.com
BC
Bob Camp
Tue, Apr 18, 2023 3:36 PM

Hi

Be careful of the combination of DC coupling / 5V and an older HP counter input.
At least on the 5535, that was a really great way to spend big bucks getting the
counter repaired. You fried the input IC and their only fix was to replace the entire
front panel board.

Back on topic … not a lot of direct experience with the 5328 so no idea if this is
an expected result. My guess is there’s something wrong somewhere ( = it’s not
normal). However, that’s only a guess.

Bob

On Apr 18, 2023, at 11:02 AM, Magnus Danielson magnus@rubidium.se wrote:

Hi,

So I fiddle around at 100-400 ns and readout turns out linearly at about half value.

The frequency is 100 kHz of the pulses, which can be tweaked, but for the moment fits is purpose.

Now, turns out that using manual setting of trigger-offset rather than auto removes the issue. I've not concluded exactly why, but it does. Will grabb the other 5328 to see if it does about the same.

Maybe I need to trim up the input side?

For reference, using TTL signal levels for this, terminate with 50 Ohm.

Cheers,
Magnus

On 2023-04-18 16:36, Bob Camp wrote:

Hi

How big a delay are you looking at?

Bob

On Apr 18, 2023, at 6:32 AM, Magnus Danielson via time-nuts time-nuts@lists.febo.com wrote:

Fellow time-nuts,

As I was testing a HP5328B in TI avg mode, it displays about half the value expected. I pulled out a SR620 to verify the proper time-delay.

I'll pick up my HP5328A with option 040 and check that one.

While I will dig into this, maybe someone remembers seeing this.

I'm not ruling out handling error or hardware error, but for the moment the signal seems OK at least.

Cheers,
Magnus


time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe send an email to time-nuts-leave@lists.febo.com

Hi Be careful of the combination of DC coupling / 5V and an older HP counter input. At least on the 5535, that was a really great way to spend big bucks getting the counter repaired. You fried the input IC and their only fix was to replace the entire front panel board. Back on topic … not a lot of direct experience with the 5328 so no idea if this is an expected result. My guess is there’s something wrong somewhere ( = it’s not normal). However, that’s only a guess. Bob > On Apr 18, 2023, at 11:02 AM, Magnus Danielson <magnus@rubidium.se> wrote: > > Hi, > > So I fiddle around at 100-400 ns and readout turns out linearly at about half value. > > The frequency is 100 kHz of the pulses, which can be tweaked, but for the moment fits is purpose. > > Now, turns out that using manual setting of trigger-offset rather than auto removes the issue. I've not concluded exactly why, but it does. Will grabb the other 5328 to see if it does about the same. > > Maybe I need to trim up the input side? > > For reference, using TTL signal levels for this, terminate with 50 Ohm. > > Cheers, > Magnus > > On 2023-04-18 16:36, Bob Camp wrote: >> Hi >> >> How big a delay are you looking at? >> >> Bob >> >>> On Apr 18, 2023, at 6:32 AM, Magnus Danielson via time-nuts <time-nuts@lists.febo.com> wrote: >>> >>> Fellow time-nuts, >>> >>> As I was testing a HP5328B in TI avg mode, it displays about half the value expected. I pulled out a SR620 to verify the proper time-delay. >>> >>> I'll pick up my HP5328A with option 040 and check that one. >>> >>> While I will dig into this, maybe someone remembers seeing this. >>> >>> I'm not ruling out handling error or hardware error, but for the moment the signal seems OK at least. >>> >>> Cheers, >>> Magnus >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts@lists.febo.com >>> To unsubscribe send an email to time-nuts-leave@lists.febo.com