HP signal generator with linear dial (from the '70s)...anyone remember?

[Wimberleytech]

Back in the '80s, I recall opening an HP signal generator that had a linear frequency dial.
Inside were two logarithmic spiral pulleys linked with a string and spring to keep them taut.

Because the spiral were logarithmic and oriented appropriately, they were able to achieve linear tic marks on the dial.

That is what I remember.  Was I dreaming?  Should I start looking for a senior care facility?

If anyone can help me validate my memory, I would appreciate it.

[Neomys Sapiens]

Back in the '80s, I recall opening an HP signal generator that had a linear frequency dial.
Inside were two logarithmic spiral pulleys linked with a string and spring to keep them taut.

Because the spiral were logarithmic and oriented appropriately, they were able to achieve linear tic marks on the dial.

That is what I remember.  Was I dreaming?  Should I start looking for a senior care facility?

If anyone can help me validate my memory, I would appreciate it.

You wouldn't be the first and only one. I once dreamt a complete meeting on a complex technical topic, in detail, with the agenda, the course of the discussion and the layout of the notes that I had been taking.
Which I could not find, mysteriously. It took my boss some time to convince me by pointing out that the meeting on the previous day, of which I thought that it preceeded the meeting in question, was the last one happening. I was really, really confused. It was simply too vivid and detailed.
That project did eat my mind and soul, taking large bites.

[KE5FX]

8640A? 

[Wimberleytech]

8640A?

No.  There was no digital display.

[KE5FX]

8640A?

No.  There was no digital display.

Right -- the 8640A is the 8640B with a slide-rule dial. 

It fell short of the 8640B in the sex-appeal department, so they don't seem to have sold many.  I think I've seen one, maybe two of them in my life...

[TimNJ]

3310A, 3312A? But pulleys..im not too sure about that.

[CatalinaWOW]

8614A has the logarithmic cams you describe, and a "digital" display in the form of a mechanical counter which is tied to the gear train driving the cams.

[Wimberleytech]

8614A has the logarithmic cams you describe, and a "digital" display in the form of a mechanical counter which is tied to the gear train driving the cams.

BAM!