From our owner and head engineer, Chris:

Well, it’s been a while since I’ve introduced a new part and here it is, AND the revision is done.

Our STV-X+ replaces the Sanken STV series of “Silicon Temperature Compensating Diodes”. It is not a Varactor diode. I’ll explain the difference later, and hope a picture is worth a thousand words.

I was working on an SX-1010 the other day and needed the STV-3H. I had two in stock, but I realized I should make some.

My part is four diodes in series with solder pads. Each solder pad you bridge, you are shorting out one junction. You can choose to have 0, 1, 2, 3, or 4 junctions. So three different part numbers can be replaced with my single part. Four, if you need a wire with a mounting hole in it.

I did tests at 6mA like older designs use. TWO of the junctionas are BAV99 signal diodes and TWO are BAT54 Schottky. The result is a +/- 100 mV match to a new STV-4 I have in stock. I carefully matched the physical dimensions best I could, including the U shaped mounting hole.

As for the VARACTOR diode confusion:

The SC-15 and SC-20 SILICON VARACTOR DIODES are voltage variable capacitors mainly used in electronic tuners. The STV-3H and STV-4H SILICON TEMPERTATURE COMPENSATING DIODES are for stabilizing bias in amplifers. In the Sanken Databook they are on the same page. There is at least one photo of a Marantz parts bag perpetuating this error.