Testing the TK Tar Baby

[picowatt]

It didn't look right when I changed it, now I see why, thanks. I've updated the schematic. Should be ok now.

The battery power measurement changed to -32W (-128W accounting for R_CSR=0.25), and the average current for both the FG and Q2 Source is now 210mA.

.99,

Also, just to be a bit "picky", the FG/ M1 source current is bypassing the CSR due to the FG common being at ground.  Can you connect the FG common to the top of the CSR (or location 4)?

I am not exactly sure of the best location for Losc with this modification.

MODIFIED, removed "...cut the trace...

PW

[TinselKoala]

TK,

I would consider MH's "series cap replacing a battery" as a second (excellent) test of a "rundown" type test independent of the pos/neg mean pwr test bypassing all or one of the batteries.

Have you tried placing some caps across the batteries yet just to see how this affects osc?

PW

No, still charging batteries. 

But I did get my radiator back from the shop--- they had initially welded it back together with the top tank on backwards.... and I installed it and put some kind of fluorescent pink chemical wetting agent in with the water and a little coolant (15 percent mix) and took it out for a half-hour spin at 70-75 mph... and my cooling problem is solved !! It's too bad I didn't actually test a before-and-after with the pink wetting agent, but the overall result is dramatic.  Of course a cleaned out radiator and going to more water in the mix makes a lot of difference and the signal from the wetting agent would be riding on top of that, so to speak....

[picowatt]

No, still charging batteries. 

But I did get my radiator back from the shop--- they had initially welded it back together with the top tank on backwards.... and I installed it and put some kind of fluorescent pink chemical wetting agent in with the water and a little coolant (15 percent mix) and took it out for a half-hour spin at 70-75 mph... and my cooling problem is solved !! It's too bad I didn't actually test a before-and-after with the pink wetting agent, but the overall result is dramatic.  Of course a cleaned out radiator and going to more water in the mix makes a lot of difference and the signal from the wetting agent would be riding on top of that, so to speak....

TK,

Seems a bit lite on the coolant.

How long do you think before batts are topped off? 

Other than the big electolytics, and the 500pF's, no other caps around?  If I could throw that far, I'd heave some .22 polys and a handfull of .1 ceramics your way!  Any old PC supplies, etc. laying about to scrounge from? 

PW

[TinselKoala]

TK,

Seems a bit lite on the coolant.

It's what the expensive bottle of pink stuff recommended for passenger cars. Racing: use pure water plus this stuff. By the time I'm in cold weather again I'll richen the mix with glycol, but now in the Texas early summer.... so far so good.

How long do you think before batts are topped off? 

I dunno. Two done, one almost done, one still flat, and the two "setasides" won't take as long, probably. Then I "usually" like to let them set for some time, check opencircuit voltages and so on.
Don't worry... we'll get there in time for the funeral.

Other than the big electolytics, and the 500pF's, no other caps around?  If I could throw that far, I'd heave some .22 polys and a handfull of .1 ceramics your way!  Any old PC supplies, etc. laying about to scrounge from? 

PW

Oh, I have a few other caps lying around. I've got about a hundred or so  30kV, 400pF doorknobs for example, N4700, but you probably don't want me to use those.

Man, this is a tough crowd tonight. Do you know what this reminds me of? When I was working on the Mylow farce, his proponent here WattsUp who moderated the thread we were on, kept denying that Mylow could have done it the way I said he did, and he kept coming up with more and more tests to perform. Like this one:
http://www.youtube.com/watch?v=ofkXAtAhqO8

Meanwhile.... I found a few other capacitors in my boxes.

The blue ones are RIFA PHE 820 M, 1 microFarad 275 V. The silver cylinders are 10000pF poly 500V and are indeed quite snappy even if low in capacity. I cut one open with a bandsaw once and it STILL was able to give me a shock, just the half-capacitor. And the little cylinders with axial leads are 0.1 uF monolithics, 100 V.

What do you think? (ETA: I also have some tantalums but I don't really want to subject them to the Ainslie component-destroyer. But if necessary..... why not. )

[poynt99]

Is this the sim that has issues with Rgen=50R?  Even with V1 at more like -12V to -15V?

All my sims of this circuit have an issue with the 50R resistance. It's not an issue of bias voltage or current (i.e. the bias voltage makes no difference), the problem is the AC impedance presented by the 50 Ohms. As I said many times, with the sim at least, there has to be a low impedance path to ground for the oscillation, and 50 Ohms is too high. 4 Ohms works perfectly with the sim.

I really like your sim work...

PW

Thanks.