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THE AM BULLETIN BOARD => Military Amateur Radio Section => Topic started by: KA3EKH on June 09, 2025, 09:59:43 AM



Title: WS-19 Modulation
Post by: KA3EKH on June 09, 2025, 09:59:43 AM
Picked up a WS-19 at Hamvention, its 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 a 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 drive the 807 as a plate modulated transmitter? figure maybe I can find a old tube CB that I can take the modulation transformer out of.


Title: Re: WS-19 Modulation
Post by: KA3EKH on June 17, 2025, 01:54:25 PM
OK smart people, I know you are out there so lets hear from you! been working on this project and so far gutted the "B" set and removed it. The B set had a modulation transformer that was feed by a signal 6V6 tube running along at 250 volts on its plate. Figure that was good for maybe a watt or maybe two of audio. I would like to use that old modulation transformer that was in the VHF B set to modulate the 807 in the A set transmitter. The 807 chugs along with around 500 volts on it plate. It was screen modulated but been told the 19 suffers from piss week modulation so was thinking of changing it over to plate modulation. The question is will one 6V6 at 250 volts be enough to drive the 807 PA?
I do not care about power with this set and would be happy with two watts as long as its well modulated.
Any comments?


Title: Re: WS-19 Modulation
Post by: Opcom on June 19, 2025, 01:46:40 PM
I'm sorry I know nothing about that set


Title: Re: WS-19 Modulation
Post by: KA3EKH on June 20, 2025, 02:35:54 PM
British sets are fun, just different enough to make you wonder why they did things so different then US manufactures. Also worked on several German radios from WW2 and that's interesting.
The WS-19 family of radios came out around 1942 or so and the mark 3 version was produced in huge quantities in the US, you often find them in both Cleric and English being built for lend lease.
This set is a original British built Mark 2 and fell into my hands out at Hamvention this year. Allays wanted the more primitive WS-1 radio being that was first produced in 1938 but not many around today.


Title: Re: WS-19 Modulation
Post by: SM6OID on July 11, 2025, 04:13:11 PM
Hi!

I have a SET No 19, mkIII Brittish.
It modulates well with a mic preamp!
AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands