(Jeffrey Dutky) wrote in
om:

I keep seeing messages about the Tek 24xx faulty horizontal output
chips. Now, I don't actually HAVE a 2445 or 2465 (much less, one
suffering from a faulty U800 chip) but I'm very curious. The
descriptions of the chip and the effects of its failure suggest that
U800 is some kind of high frequency amplifier. Wouldn't it be possible
to rig a replacement for the chip from discrete components? What are
the specifications for the chip?

- Jeff Dutky


TEK no longer knows what the specs are,their IC/hybrid manufacturing unit
was sold to Maxim long ago,who then forced a last-time buy and ceased
production of TEK-made ICs(155 and 234 prefix ICs).That's what terminated
the 2400 product line.I doubt you could get Maxim to release the specs.
TEK will have nothing to do with these scopes.

This H-output amp is a differential output amp with high linearity and very
high freq response(to display a 100PS/div sweep,IIRC),designed to directly
drive a CRT's plate capacitance with a specific deflection sensitivity,and
it also has programmable gains,and IIRC,switches in the readout signal and
external horizontal inputs.It's not a simple IC, but a combo analog/digital
IC.

Bottom line is that there is not enough product base to cost-effectively
support a reverse engineering effort.

BTW,this has been discussed in this NG (or sci.electronic.design) before.


--
Jim Yanik
jyanik-at-kua.net

See the tekscope group at yahoo.com

There have been several threads on this problem and there appears to be no
repair.

Hugh



"Jeffrey Dutky" wrote in message
om...
I keep seeing messages about the Tek 24xx faulty horizontal output
chips. Now, I don't actually HAVE a 2445 or 2465 (much less, one
suffering from a faulty U800 chip) but I'm very curious. The
descriptions of the chip and the effects of its failure suggest that
U800 is some kind of high frequency amplifier. Wouldn't it be possible
to rig a replacement for the chip from discrete components? What are
the specifications for the chip?

- Jeff Dutky