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Jeff, the foot is packaged up in a USPS Small Flat Rate box. Hopefully I will remember to mail it tomorrow and you will likely have it Monday. You should have received an email from the USPS with the tracking number; if not yet then you should when they have the package. Just remember to save my shipping label for the return address.

Now to find a source for 2445 and 2430A feet....

I have a few hundred microfiche, Grundig and NordMende service manuals,
some Ducati parts manuals, plus a few Ford ones. I have had various full
size flatbed scanners complete with transparency adaptors, but so far
attempts at scanning fiche have been unsuccessful. I have considered
setting up a digital camera to take photos of the screen of my fiche
reader, but not done so.

A few years ago I came across a large office size fiche scanner with
built in photocopier. I could not get service info (not surprising
really), but with a pal, we attempted repairs. We found and fixed a
number of faults, but in the end had to give up in view of no technical
info or circuits, so it went back to scrap. I think I saved lenses etc.,
but never found a use for them.

If anybody does successfully scan with a high end vanilla scanner,
please let me know. I often felt that the Canon scanners would be
suitable candidates, but their high end models had no linux drivers
available, so no chance with those.

Les.


On 29/03/18 12:37, cnc_joker wrote:

The quality of images in most microfiche that I have used is quite
poor. Perhaps using
a high resolution bed scanner would be sufficient. I have an Epson
V700 scanner
that has real optical 4800 DPI resolution and 9600 DPI if you use
sub-sampling. There
may be even higher resolution scanners that don't cost a lot of
money. There are up to
14 page images across the 4 inches width of a microfiche. My
scanner would get about
150 DPI (300 DPI sub-sampled) on a single page which should be good
enough to get a
usable image.

This would get all the images on the microfiche in one scan. There
would be some
work in breaking out each page and assembling them into the proper
order. That
work could be farmed out to all of us that are interested. The
Museum could just
post the full scan of the microfiche and we would do the rest.


I may try scanning a microfiche if I can find one around here. I
cleared a lot of old manuals
out of my lab when PDF's became more convenient. My old microfiche
may have gone out as
well.

Pete.

The common mode input range of the P6046 is only 5 volts which becomes
50 volts when the x10 attenuator head is used. This is typical of
other high bandwidth low voltage active probes.

High voltage differential probes typically allow 240 volt AC line side
measurements so they support a common mode input voltage of at least
400 volts and usually several times that.

On Thu, 29 Mar 2018 09:44:37 -0400, you wrote:

Thanks David. This is very educational. What range do you classify as low
voltage?

On Thu, Mar 29, 2018 at 9:38 AM, David Hess <davidwhess@...> wrote:

The P6046 is a low voltage differential probe and not intended for or
really suitable orapplications where isolation is required.
Essentially it is a high voltage differential probe with the matched
high voltage input attenuators absent.

Shorting one side and using it as a single ended probe completely
defeats what isolation that it does provide; it just becomes a low
voltage active probe when used like this. The schematic from Bob
Pease that I linked shows how to make one of these. 100 MHz for an
active probe may not seem fast but these are used where input
inpedance must be as large as possible.

Where the P6046 is useful is making low voltage measurements where the
oscilloscope and DUT (device under test) share a ground but the
measurement itself either needs to remove ground noise or is a
differential signal.

Thanks David. This is very educational. What range do you classify as low
voltage?

On Thu, Mar 29, 2018 at 9:38 AM, David Hess <davidwhess@...> wrote:

The P6046 is a low voltage differential probe and not intended for or
really suitable orapplications where isolation is required.
Essentially it is a high voltage differential probe with the matched
high voltage input attenuators absent.

Shorting one side and using it as a single ended probe completely
defeats what isolation that it does provide; it just becomes a low
voltage active probe when used like this. The schematic from Bob
Pease that I linked shows how to make one of these. 100 MHz for an
active probe may not seem fast but these are used where input
inpedance must be as large as possible.

Where the P6046 is useful is making low voltage measurements where the
oscilloscope and DUT (device under test) share a ground but the
measurement itself either needs to remove ground noise or is a
differential signal.

On 29 Mar 2018, at 13:56, Chuck Harris <cfharris@...> wrote:

Once upon a time, I scanned a $20 bill on my scanner in
full subscanned resolution, and I got a humongous file, I think
it was 10 or 20 Mb. The resolution was astonishing! I could
see the individual ink dots, and the cell structure of the
paper used to make the bill.

I think it is very possible that you could scan the individual
sheets of microfische on a good scanner. You might need to do
something to make the lighting consistent.

I have a couple of boxes of fische... I think I will give it a
whirl.

-Chuck Harris

cnc_joker wrote:

The quality of images in most microfiche that I have used is quite poor. Perhaps using
a high resolution bed scanner would be sufficient. I have an Epson V700 scanner
that has real optical 4800 DPI resolution and 9600 DPI if you use sub-sampling. There
may be even higher resolution scanners that don't cost a lot of money. There are up to
14 page images across the 4 inches width of a microfiche. My scanner would get about
150 DPI (300 DPI sub-sampled) on a single page which should be good enough to get a
usable image.

Pete.

The P6046 is a low voltage differential probe and not intended for or
really suitable orapplications where isolation is required.
Essentially it is a high voltage differential probe with the matched
high voltage input attenuators absent.

Shorting one side and using it as a single ended probe completely
defeats what isolation that it does provide; it just becomes a low
voltage active probe when used like this. The schematic from Bob
Pease that I linked shows how to make one of these. 100 MHz for an
active probe may not seem fast but these are used where input
inpedance must be as large as possible.

Where the P6046 is useful is making low voltage measurements where the
oscilloscope and DUT (device under test) share a ground but the
measurement itself either needs to remove ground noise or is a
differential signal.

On Tue, 27 Mar 2018 16:26:37 -0700, you wrote:

Thank you everybody for the feedback so far. Sorry I have not responded

sooner. Just to be clear, my primary interest is in the isolation
characteristic of the differential probe as a safety precaution. I already
do a lot of things for lab safety... I have an isolation transformer and a
current limiter that I typically plug into. But, I also watched how Dave
on the EEV blog has recommended differential probes at the end of his video
() on how not to blow up your oscilloscope.
I'm not desperate for one. Between my current lab set up and my best
practices, I think I've got things pretty well covered. But, I occasionally
see the entire P6046 kit come up for sale and was wondering if it's
worthwhile for its isolation capabilities and if it's easily adapted into a
regular (CRO?) probe.

Thank you everybody for the feedback so far. Sorry I have not responded sooner. Just to be clear, my primary interest is in the isolation characteristic of the differential probe as a safety precaution. I already do a lot of things for lab safety... I have an isolation transformer and a current limiter that I typically plug into. But, I also watched how Dave on the EEV blog has recommended differential probes at the end of his video () on how not to blow up your oscilloscope. I'm not desperate for one. Between my current lab set up and my best practices, I think I've got things pretty well covered. But, I occasionally see the entire P6046 kit come up for sale and was wondering if it's worthwhile for its isolation capabilities and if it's easily adapted into a regular (CRO?) probe.