On the amateur radio subreddit, some guy posted a link to his ePay store where he’s selling fancy crystal radios. Since there’s a rule that you can’t post ads, his post was quickly removed, but not before I clicked on a link and got a look at his work. Honestly, some of it looked pretty interesting, but there was one thing he was selling that I questioned.
One of his products is a little board with four germanium diodes in parallel (see below). I’m going to guess that these are 1N34A diodes. When I asked him what the purpose was for connecting four diodes in parallel like that, he replied, “To decrease the Diode Resistance so it improves the Diode performance in a Crystal Radio (his caps, not mine).”
Now, it’s true that connecting resistors in parallel will decrease the total resistance, but let’s look at a typical crystal radio circuit:
This circuit uses high-impedance headphones or a high-impedance earphone because there is no powered amplifier. The only power comes from the received radio wave itself. This means that very little current will be flowing in the circuit, so there’s really not much to gain by decreasing the “Diode Resistance.”
So, to answer my own question, no, I don’t think that paralleling diodes in a crystal radio circuit would make it work noticeably better.
