[sdiy] MC1495 multiplier chip discontinued completely

[Grant Richter]

Raytheon started the RC4200, now second sourced by Japan Radio Corporation
(JRC). Part number NJM4200. People are confused by the low price (last
quoted as $0.68 per 1000). It requires more external support than a AD633,
but the specifications are 10X better.

It is a single quadrant sum of logs multiplier which has to be offset for
bipolar operation.

Linearity is 0.1% and DC drift is 0.005% per deg C due to internal
monolithic construction. Very clean and pure sounding.