Fluke PM6666 counter freezing after 3 seconds from turning on.

[shakalnokturn]

I don’t have the 6669 any more- waiting on an Hp 5385a with which I replaced it.

But the next person who runs into a freezing PM6666 that has both GPIB and MTCXO could give it a try.

[FransW]

I don’t have the 6669 any more- waiting on an Hp 5385a with which I replaced it.

But the next person who runs into a freezing PM6666 that has both GPIB and MTCXO could give it a try.

I am wondering whether this a TE step forward.

However, it gives me the time to pdf the service manual and upload to KO4BB.

Frans

[0xdeadbeef]

If I pull the MTCXO board, the counter won't start anymore.
I didn't get why you guys would suspect the MTCXO board anyway. It's working fine and from the previous discussion, it seems clear that the fault is clearly related to the GPIB board.

[pizzigri]

May I also add that, differently from 0xdeadbeef, my PM6666 never showed (and still doesnt show) any freezing or problems of any kind as long as the GPIB card is removed from it. So it is the card undoubtedly, in my case, causing the lockup. And, the card works perfectly in the PM6669, and viceversa, the card from the 69 freezes the 66! Bah

BTW, I have been doing some tests and been surprised with the stability of the MTCXO, I thought it would have been some sort of gimmick instead it actually works, at least as well as a decent TCXO. Definitely better than the TCXO from the HP5385, that's for sure...

I havent given up, but the meter is reassembled and working as a standalone counter for now. And again, I want to thank everyone for your time spent trying to help me!

[pizzigri]

I don’t have the 6669 any more- waiting on an Hp 5385a with which I replaced it.

But the next person who runs into a freezing PM6666 that has both GPIB and MTCXO could give it a try.

I still have the PM6666, I sold the PM6669, which btw worked perfectly.

[0xdeadbeef]

May I also add that, differently from 0xdeadbeef, my PM6666 never showed (and still doesnt show) any freezing or problems of any kind as long as the GPIB card is removed from it.

Why would you say this? I never removed the GPIB card. At the moment my counter starts most of the time anyway, so removing the GPIB card would just be my last option if it should freeze all the time at some point.

[pizzigri]

May I also add that, differently from 0xdeadbeef, my PM6666 never showed (and still doesnt show) any freezing or problems of any kind as long as the GPIB card is removed from it.

Why would you say this? I never removed the GPIB card. At the moment my counter starts most of the time anyway, so removing the GPIB card would just be my last option if it should freeze all the time at some point.

Because my Pm6666 never starts up if I leave the GPIB card installed inside - it just does not work. Yours at least still works most of the time, so there is no need to remove the GPIB card. You see, differently from you, removing the card WAS MY last option....
I admit the phrase was not clear.

[Xgentec Jason]

Well now you lot have gone and done it.
I get caught up in reading every thread in this subject and now I have gone and bought the Fluke Pm6666 with Pm9604 for testing.   

The Fluke meter just arrived. Tested frequency calibration and it is spot on but further function testing tonight.

[Engineer1]

Hi,

Apologies for the archaelogy. I just read this thread with interest. I have the same PM6666. It had very similar behaviour, but after a few power cycles it would always come good. I haven't used it for probably about a year. Sadly now it fails at about the 3s point every time. This makes me feel it's an age related problem.

Thank you OP for the GPIB board discovery. I disconnected mine and now the unit is fine. I don't use GPIB anyway, so it's no great hardship. But, probably like the rest of you, it doesn't feel nice knowing the unit is compromised! Did you ever get the bottom of the problem?

Maybe one day I will have a poke about inside it myself to see if I can discover anything useful. Although the diagnostics carried out by you and others through this thread were pretty comprehensive.

Thanks again.