Testing the TK Tar Baby

[TinselKoala]

I don't recall if you can enter a constant in the Tek scope to multiply against any channel, but I believe you can.

TK, if you want, try placing your DMM meter across V1-V2 and see if you get a sensible stable voltage reading. If you do, enter this value as a constant multiplier with the VCSR and you'll have an accurate PBat computation. You can try this with and without the capacitor filtering across the batteries. Pending little RF interference in the meter, this should give you a relatively solid and accurate VBat reading.

Yes, you can. The Tek that Tar Baby plays with has only one math channel too, but it can be programmed for two numerical constants to be used with whatever nested set of arithmetic and integrating operations you like on live or stored or combinations of live and stored traces. At least that's what it looked like on-screen; I haven't RTFM yet.
I could also have the scope compute a simple average of the battery trace and use that in the power computation, the equivalent of heavy filtering.

[picowatt]

Well, I thought we wanted to stay away from electrolytics. But sure, I have caps in that range and I don't even have to take anything apart to get to them.
There just might be something in this box I could use. The ones at top left are Mallorys and Spragues, mostly.

TK,

I saw more oil than electros in that bin!

You don't need to get carried away.  100-470uF electrolytic for bulk uF and then parallel a couple of the smaller caps to improve the HF characteristics of the electro.  Very common practice.  MH with his digital experience I am sure will attest to this.

In any event, I am sure you fully grasp what I am saying.  It's probably just another low ball.

I wish you good luck, safe driving, and no more vehicle issues regarding tomorrow's journey! 

PW

[TinselKoala]

There are a few oil filled motor caps of low capacity in there, but most of them are indeed higher value electrolytics. The short grey cylinders are 4700 uF 50 VDC and there are about 20 of them in there, and there are also several more power supply filter electrolytics buried under there, some multiple section filter caps, and even a couple of high-voltage caps in there. The white cylinders are just a few of the 400pF30kV doorknobs that I have lying about. (These can be seen in action on my "dirod" video and similar ones are used in my "bonetti" videos.)

I don't have a lot of mica caps, though, and I wish I did.

[picowatt]

There are a few oil filled motor caps of low capacity in there, but most of them are indeed higher value electrolytics. The short grey cylinders are 4700 uF 50 VDC and there are about 20 of them in there, and there are also several more power supply filter electrolytics buried under there, some multiple section filter caps, and even a couple of high-voltage caps in there. The white cylinders are just a few of the 400pF30kV doorknobs that I have lying about. (These can be seen in action on my "dirod" video and similar ones are used in my "bonetti" videos.)

I don't have a lot of mica caps, though, and I wish I did.

TK,

Always gotta' argue...

PW

[picowatt]

TK,

You could always gather up all the window glass from your house and a few rolls of foil... make some..

PW