To increase the level of modulation the control unit #10 was designed. It goes between the set and the first regular control box. It uses the intercom amplifier to increase microphone levels. Although the #10 is  not very common other people have modded regular boxes as a substitute. The No. 10 Control box is easy to replicate, just a switch and a few resistors. All it does is switch the output of the amp circuit into the mic circuit. It requires no mods to the set itself.

Bruce  M0SOE

On 09/06/2025 15:02, Ray Fantini via Milsurplus wrote:

Picked up a WS-19 at Hamvention, it’s a basket case so have no problems doing some modifications to it. Started by removing the VHF set and am now in the process of replacing tons of capacitors and lots of the old brittle wiring.

The goal is to end up with a another low power AM transceiver that I can run at events.

In addition to the VHF junk that's been removed they also had an intercom audio amplifier in the set and have been thinking of using that to drive a speaker or better yet as a modulator for the 807 in the PA. The existing circuit uses a grid modulation system but wondering if anyone ever used the 6V6 in the intercom amplifier to modulate the 807 as a plate modulated transmitter? figure maybe I can find an old tube CB that I can take the modulation transformer out of.

 

Ray F/KA3EKH