F Knobs vs F Buttons on Signal Generators

I'm not familiar with those generators. Do those have many knobs? Or, with some button pressing, a single 'master knob' is assigned for say f,offset or amplitude adjustment?

D from BC British Columbia Canada.

The 3325B has all buttons. I see a knob on the HP8660.

I'm interested in who rules for the 2 classes of generator users.

Test Equipment | +----- +-----+ | | Button Knob Pressers Turners

However, I'll probably buy any cheapo generator. Knobs or not.

D from BC British Columbia Canada.

There are a couple, but it depends on the plug ins

Both have computer interface to use for SATE or ATE applications. The 8660 was a '70s product, full of TTL. You could program it, then use the tuning knob to move in discrete steps.

I used the 3325B to test and align video boards, and to find the integration time of the AGC systems.

There's a quite nice optical encoder on the motor in the original (boxy rectangular) HP deskjet, but it's been supplanted by a strip encoder in the newer models. The part number of the reader is odd, but the pinout is the same as the standard HEDS modules (see US Digital website).

If you get one of the old ones, don't try to take it off the motor, just use the motor as a spindle bearing and mount a knob over the gear somehow. Forget the resolution, but it should be sufficient when run with quadrature decoding for most purposes.

I think one of the issues actually is that for navigating menus you need a coarse encoder with detents, but for tuning frequency (on an HF band for example) you really want a wheel with some mass, fine resolution, and no detents.

Well, there's no law against having more than one encoder. The second type costs a LOT more money, so adding a few cheap ones isn't very significant cost-wise. CNC machine tools have some of the finest encoders I've used.

Best regards, Spehro Pefhany

Which reminds of.... I have digital calipers that go down to 1/1000". I wonder how that works.

D from BC British Columbia Canada.

Yes.

Indeed. Just run a few mA throught the windings and you'll have a simple-to-detect-signal.

I was once working at some outfit where one of their products was very much like a scanning electron microscope (SEM). It had buttons for magnification and focus and stuff, and it was frustrating as hell, because you'd hold the button down and watch the image come into focus, and when you released the button, it would "coast", as if there were a flywheel on a knob. This is ludicrous, of course, because it was digital. Obviously, the programmer was incompetent, as most high- buck programmers are.

But the point is, one day my engineer was sitting at the console of one of these things, dicking around with the focus buttons and so on, and summed it up very concisely:

"I'd rather have a knob."

Cheers! Rich

Something like two scales like a vernier, and read the interference patterns?

Cheers! Rich

That same programmer did my Fuji E510 cam. It's normal electronic "autofocus" is ever so slightly out, (hence the cam is f****** useless) and it's "manual focus" mode involves pushing buttons to try hunt the motorised lens back and forth while peering at a pixely screen. Methinks this prolific offender needs searching out and punishing in some rather cruel and unusual manner. As aside ... was talking to a young guy today who'd just got a degree in Computer Aided Engineering. Seems much of his course time was spent on 'business practice' and 'case law'. Seems like our so called educators deserve to shoulder much of the blame for the crap products out there.