Btw, it seems that the Intel 4004 was not used in any probes http://en.wikipedia.org/wiki/Intel_4004#Use .
The Voyager probes do not contain microprocessors, I believe its all discrete logic. See http://voyager.jpl.nasa.gov/faq.html

Question: How fast are the Voyager computers?

Answer:Not very fast compared to today’s standards. The master clock runs at 4 MHz but the CPU’s clock runs at only 250 KHz. A typical instruction takes 80 microseconds, that is about 8,000 instructions per second. To put this in perspective, a 2013 top-of-the-line smartphone runs at 1.5 GHz with four or more processors yielding over 14 billion instructions per second.

On the other hand, the data transfer rate was 115.2 kbps at the distance of Jupiter, which is roughly as fast as my EDGE internet connection was in 2005. Boggles the mind that they did achieve such a data rate without microprocessors and in the mid 70s . Also, its internal data storage is a 62.5 MB tape recorder, which is bigger than most consumer hard drives until 1993.

A tape recorder! It is astonishing that they could engineer a mechanical component that could take that kind of strain.

Also no digital, only 'steam-powered' cameras in 1977 😀 :

"... The Voyagers use vidicon cameras. They are modified versions of the slow scan vidicon camera designs that were used in the earlier Mariner flights. The design is a 25-mm diameter magnetic deflection vidicon, built by General Electro-dynamics Co. The vidicon storage surface (target) is selenium sulphur and can store a high resolution (1500 TV lines) picture for over 100 s at room temperature. The active image area on the target is 11.14 x 11.14 mm. Each frame consists of 800 lines with 800 picture elements (pixels) per line, i.e., 1 pixel = 14 microns. One frame requires 48 s for electronic readout.

The readout signal is analog; it is amplified, filtered, and converted to 8-bit digital. Then it is saved on an on-board digital tape recorder. From there, the digital picture is sent back to Earth by radio ..."

It's just amazing the Voyagers are still (partially) alive & kicking, 36 years and 124 AU later.

48 seconds is a tiny delay compared to the time it takes it to arrive back to Earth because of light speed. Hell, most Amiga games took more than 48 seconds to load from the floppy drive.