On Sun, 1 Jul 2012 20:59:15 -0600, David DiGiacomo
<daviddigiacomo@...> wrote:
On Sun, Jul 1, 2012 at 5:29 PM, raymonddompfrank <r.domp.frank@...> wrote:
Recently, I acquired a 7B92A that in contrast with the unit that I had, turns out to have no (discrete?) tunnel diodes in the trigger circuits but instead, uses hybrids packaged like the ones in e.g. a 7904A's vertical amp. I have seen references to this newer version of the 7B92A but haven't been able to find any description of the reasons why and any possible consequences. I would guess (and could appreciate) lower cost, higher reliability?
I wonder whether the circuits in these hybrids still contain circuits with tunnel diodes or do they contain more traditional circuits and if so, are there any functional differences? i could imagine that the maximum signal that the unit will trigger on would be lower than the tunnel diode-equipped version.
No, there are no tunnel diodes in the late version. I thought the
trigger circuits were monolithic ICs, but maybe not.
I have found the early version to be faster, but others disagree.
I only have the later 7B92 plug-ins or I would do some tests. Both
versions include the HF Sync mode. I like them because they trigger
more cleanly than the 7B53A which is to be expected.
I thought they used monolithic ICs instead of hybrids also but that
could still be the case. Tektronix may have used that package for an
IC simply because it was the highest frequency IC package available to
them.
It is too bad there are no details on it.
David Hess