Fluke 6070A

[s***@gofree.indigo.ie]

I recently purchased a Fluke 6070A RF Signal Generator on eBay.
While I was playing with it I noticed that the Spin Knob has 18
magnetic detents per full revolution resulting in 18 counts per
compleat revolution instead of the 25 counts per revolution that both
the user manual and datasheet say it should have.
Also the Instruments default setting when turned from the cold is:-
Freq. = 300 MHz and Amplitude = -10 dBm. (This instrument does not
have the Non-Volatile Memory option fitted i.e. -570 ) where as the
standard power-on setup listed on page 5E-2 of the Operator Manual
states that the Frequency ddisplayed should be 250 MHz and Amplitude
-60dBm. I also have my suspicion with regard to the FM deviation
limits but that's a bit more complicated to check as there is an
interaction with the Modulating frequency and Output frequency.
The guy I bought it from says he has a number of these all the same.
So what have I actually got ? I can find no reference to it on the
internet
Were there a couple of different versions or did they do custum
versions for some customers. ?
Apart from this the instrument works as expected.

[jstearns]

There are probably several versions of the front panel knob.

When we started shipping the product, the knob's mechanical design was tricky and needed careful adjustment.

Oh, but when that knob was aligned, it was magical. It felt like a million bucks in your hand. It spun like a top and magically coasted to a stop like something from the control panel of a spaceship. But it needed tight tolerance for the magnets to have the right feel.

During the years that we manufactured the generator, we kept trying different designs and manufacturing techniques for the knob in hopes of making the mechanical design simpler, cheaper, and easier. I left the team by that time, but I know from talking with them that they were still trying to reduce manufacturing cost and the need for alignment. It does seem likely that some later versions of the product had knob internals that differed from the original design