[Milsurplus] mystery diode in the PRC-74

[kgordon2006 at frontier.com]

As I remember it, a 1N34 will withstand around 50 volts at something like 50 mA output  That 
diode looks awfully small in that photo. From what you have said, it is used to simply drive the 
tuning-meter. Is that correct?

What are the ratings/characteristices of the meter and its circuit?

If that is all correct, I would concur with trying a Schottky diode. Those have very low reverse 
resistance and should work well there. They MIGHT show higher output than exists in reality, 
but I think all one needs from that meter is an indication, not an exact figure.

Ken W7EKB

On 15 Sep 2025 at 13:13, Ray Fantini via Milsurplus wrote:

> 
>     Couple questions about what the diode (CR-15) looks like and where its located. 
>     Attached is a picture of the early style PA deck for the PRC-74 and where the diode is 
>     located, somewhat hard to see but its there. You can get an idea of size in comparison 
>     to the other diodes in the amplifier. Also note that on this amplifier there is no circuit 
>     card but everything is point to point. According to the manual this dose not exist but after 
>     all it is a early unit, serial number 8, the rest of the radio is the same as every other 74 I 
>     have seen.
>     At this point am leaning towards installing a 1N34A just have to worry about if it will 
>     stand up to the power. Figure that someone must have run the radio up without a 
>     antenna and maybe that´s why the original diode failed? Or maybe its because its over 
>     sixty years old? Who knows.
>     
>     Ray F/KA3EKH
>