8662 & 8663 Sig Gens

[flew-da-coup]

I hate when the power supply dies on a 8662! The 8662 & 8663 power supplies suck. Don't you hate when you think you are going to have a good day and you plan on calibrating two 8662's and get them out the door. And then it happens. You turn them both on only to get nothing. It seems like one out of 10 will have a dead power supply. Does anyone else have this problem or is my luck bad?

[flamy78]

I guess that's why we are having issues with one or both. Do we have two 63s? Right well one was stuck or wouldn't go to standby. It was fixed after another problem developed. That one is due cal now and the other is apparently AWP. So Jorge says.

[flew-da-coup]

They are great when they turn on.

[mdbuike]

We've found that replacing all the electrolytic caps on the A7A3 card helps, especially the pre 90's models.  Those caps age quite fast and break down with heat.

We support over 30 of these things, and between power supplies and phase noise, we've gotten quite good.

[mdbuike]

Just came up with a new problem last week..I had FM loop problems with a couple of red lights and status flashing..after wacking the head multiple times onto the bench, came to find out the 20 V power supply had INCREASED to 22.6 volts..the regulator had gone TU, even though the little green lite was lit..

It's always back to basics..check the power supplies FIRST, and use a scope for ripple

Mike

[mdbuike]

Just came up with a few reminders last week..

1.  On the new phase noise system, modify your FFT tables to give you shorter scanwidths, there by lowerering you resolution bandwidth..many times close spurs, even though in tolerance, can give an indication of excessive noise floor (i.e. a hump)

2.  Align your FM loop occasionally..this will reduce the noise and spurs from 1K to 10 K

Just some thoughts

Mike