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[email protected] jurb6006@gmail.com is offline
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Default HP Unobtainium IC revisited (1725a)

The HP is backburnered for now. Actually my associate says he might find a third, if so and it doesn't need the same thing, fine.

I modified it by adding 680 ohms to tha 1 Ks. I saw those 680s and said "sElf, those are perfect". Problem is that when I fired it up then it owuldn't trigger. I DID give the thing a nice bath in LPS2 and it did seem to improvr things. I was going to say OK, I'll just set the gain and be done with it for now, but the gain onb the preamp wouldn't go high enough. I wasn't too crazy about doing it thart wqay anyway.

I had a bunch of pivcutre sI thought but the card got corrpupted somehow. I had a fairly decent 1Mhz square wavw on it, one I wiggled and juggled enough to get all the old comnections connectioning.

The other "good" HP ike this might need some help. ZSeems like I get better response on this one than on that one. Next time I am going to hok it up with clip leads, screw the probes. I have to look see about that Wavetek 111 I got, how it reacts to a 50 ohm load, and align it with that. Maybe put the whole damn front end from this is there, because as much as I tried, the thing just didn't seem to come out right. ringing and all this,. even in the 1Khz square wave.

I got an old 422 on a lend/lease type of deal, a Hameg and a B&K. They all work. And now we might be getting a 7633. Not sure about that though.

Anyway, got ta get a few things out of here myself. the profit potential in the HP is not great really. I know it is among the fastest analogs out there, but so what. I don't need to carefully exmine the eye pattern on a CD player or whatever, hell even scoping the Ysus in a plasma is no problem for the old 422, or even the B&K which no matter how ****ty it is, still works.. When it didn't it was some bad connections in the vertical output. Didn't need a single component.

More later. I am not co,mpletely throwing it out, butit is getting on my nerves. Why the hell would it stop triggering ?