Happened across this advertisement for Signetics' Write-Only Memory IC, which was published in 1972 - you guess the exact date of publication.

A copy of it resides here: http://www.national.com/rap/files/datasheet.pdf
Be sure to zoom in on the Block Diagram to note the handy features, and the novel Drain concept.

The "Bit capacity vs Temperature" chart on page 2 is quite illuminating, along with the "Pins Remaining vs Number of Socket Insertions" diagram. It's too bad that more vendors don't supply this kind of data.

Anyway, I'd been looking for just such a device for implementation of a non-intelligent microcontroller. Now if I could only find a FISH (First In Still Here) register I'd be all set.

 

Someone was bored that day, I'm guessing it was printed April 1st.

 

The most useful examples of WOMs are printers, card punches, and tape punches. We don't need no steenkin' read after write. Yuuuuh!

 

Now if we can only find the ad for the Electro-Voice speakers with the DC to blue light response..

 

I remember seeing that when it was first printed. Reminds me of the Darkness Emitting Arsenide Diode (DEAD). I understand the yield is very high.

 

Bob Pease wrote an interesting column about electronic hoaxes and April Fool jokes.

 

Those WOMs cost too much! I have recently discovered (4 months, 24 days ago) that I can get WOMs if I tie the /OE pin of a 27(C)xxx EPROM high! I now have a selection of WOMs from 1Kx8 (2708) to 512Kx8 (27C040)!

--Rich

 

Now if we can only find the ad for the Electro-Voice speakers with the DC to blue light response..

Have you seen the Lectrosonics XSDT?
http://www.lectrosonics.com/PressReleases/xsdt/xsdt.htm

Here's another goodie: the WA520 Wireless Antenna
http://www.lectrosonics.com/PressReleases/wa520/wa520.htm