958DC Source or Replacement

[petticoatjunction1]

Hello,

I plan on aquiring a geiger counter pulse calibrator. I found one for a very reasonable price but there is one downside. It has a broken IC. Any source for a replacement?

Any substiutions?
958DC
Binary Up Counter

Circuits Per Package=1
f(oper) Max. (Hz)=2.0M
Vsup Nom.(V) Supply Voltage=3.6
Package=TO-116
Pins=14
Military=N
Technology=RTL

 

[mneary]

My data book only shows the 8 pin TO-99 package.

For what it's worth, 14 pin RTL power and ground are on the normal corners. This part is a decade counter with reset, count, and 4 outputs.

 

[on1aag]

Hi Petticoatjunction1,

There's no replacement, the only thing you can do is
try to find a datasheet and rebuild it from scratch
with 74HC or CD4000 smd chips.
I can tell you that you're going to run into trouble
with the logic levels. The inputs of these circuits
accept voltages up to the supply voltage which is
3,6 volt. But the outputs . . .
A logic one is only 1 volt. If you reconstruct that
counter with cmos chips a logic one of a rtl circuit
will not be recognised by the cmos logic that operates
at the 3,6 volt supply voltage of the rtl circuits.
If you use 74HC logic you can lower the supply voltage
to 2 volt but a logic one from a RTL circuit will still
not be recognised.
Therefore you'll need to add level shifters at the
inputs of the reconstructed circuit.
And . . . the reconstructed circuit will become too big.
And you're gonna get frustrated and do something you
will regret.
That's not much help is it.
I also found the same specsheet as you did but I also
found that it was a decade counter.

on1aag.

 

[petticoatjunction1]

Hi Petticoatjunction1,

There's no replacement, the only thing you can do is
try to find a datasheet and rebuild it from scratch
with 74HC or CD4000 smd chips.
I can tell you that you're going to run into trouble
with the logic levels. The inputs of these circuits
accept voltages up to the supply voltage which is
3,6 volt. But the outputs . . .
A logic one is only 1 volt. If you reconstruct that
counter with cmos chips a logic one of a rtl circuit
will not be recognised by the cmos logic that operates
at the 3,6 volt supply voltage of the rtl circuits.
If you use 74HC logic you can lower the supply voltage
to 2 volt but a logic one from a RTL circuit will still
not be recognised.
Therefore you'll need to add level shifters at the
inputs of the reconstructed circuit.
And . . . the reconstructed circuit will become too big.
And you're gonna get frustrated and do something you
will regret.
That's not much help is it.
I also found the same specsheet as you did but I also
found that it was a decade counter.

on1aag.

Yes, I was leaning towards your idea. I guess I'll have to get to work. I hate SMD though

I did find a source though. 15 for $4.