开云体育

Among my menagerie is a recently acquired 2215A which I had to perform minor
repair work on, but otherwise seems to be in fine condition. I would like to
do some adjustment on channel 1, whose trace jumps up two divisions when
switching from 5 mV/div to 2 mV/div, but the service manual seems to indicate
that I should first do the performance check before doing the adjustments. The
problem, of course, is that I don't have most of the equipment specified for
the performance check. Specifically I don't have a calibration generator,
leveled sine wave generator, or a time mark generator. Looking online it
appears that acquiring any of those items will set me back hundreds, if not
thousands, of dollars.

I have a cheap 3 MHz function generator (analog, uncalibrated), a Leo Bodnar
fast pulse generator, a DM501, a DC503, a couple of fairly nice handheld
multi-meters (an Extech 22-816 and a Tek DMM916), a nice bench power supply
with current and voltage limits, and a passel of assorted components,
including crystal oscillators of various frequencies up to at least 50 MHz. Is
there some way that I can rig up something that would get me through the
performance test with some reasonable level of confidence?

I'm willing to splash out for one of the relatively inexpensive Chinese
digital signal gens (e.g. the KKmoon/Koolertron/whatever FY6900), but that's
about the limit of my budget. I've also seen shockingly cheap RF signal
generators that go way higher than anything I would need, and wondered if that
might be useful for testing my oscilloscopes (if not for actual calibration).

So far I have been relying on comparative measurements between all my
instruments of unknown accuracy. My feeling is that they all seem to be in
good shape, since their readings all agree to within a few percent. My feeling
is that I should be able to use a combination of multi-meters, counter timers,
and known voltage sources (e.g. the bench power supply/voltage regulators,
fresh batteries, etc.) to establish the accuracy of one or more instruments,
and then work outward from that stable spot, but I'm not entirely confident in
my own reasoning.

-- Jeff Dutky

chuck also for the tds700 series the same rule applies?
if I start the calibration and I don't choose "run full sequence" but I select "select sequence" but still respect all the steps from 1 to 11 is the calibration valid?
thanks
simon

I haven't got either a DMM with the socket and Hfe setting, nor do I have a curve tracer. I'm trying to limit my acquisition of new boat anchors, as I've already filled my work area with 400-series and 2200-series scopes (I started out with a 475 and a 2213 that belonged to my father, then I bought several parts 475s, one of which is a 475A, in order to ensure that I could keep my father's scope running. Then I saw that the 2215 had a neat feature that the 475 lacked, and was pretty cheap. Finally, after losing an auction for a 475A+DMM44 I saw that there was a 2200-series scope, the 2236, with a DMM/Counter-timer built in, and now I am up to my ears in scopes).

I'm a little surprised that I haven't seen an external curve tracer that could be attached to a scope operating in X-Y mode. I know that you can do some kinds of component checks using a scope in X-Y mode, but I haven't gotten around to learning exactly how to do that.

I've been wanting to get a reliable ESR meter, and some of them appear to have component test sockets as well, but the range of choices has been beyond my analysis-paralysis threshold. If someone had a solid recommendation for a reliable, but not too expensive meter with these features, I would be grateful for the suggestion.

-- Jeff Dutky