[Boatanchors] 1930's era cw transmitter

[Glen Zook]

For the 807, my RCA Transmitting Tube Manual, Technical Manual TT-5, copyright 1962, lists the CCS plate input rating for r.f. power amplifier amplifier Class C telegraphy and FM telephony as 60-watts.  The ICAS rating for the same is 75-watts.

The rating for Class C telephony is 40-watts for CCS and 60-watts for ICAS.

Typical power output for CCS Class C telephony is 28-watts and for ICAS 44-watts.  For Class C telegraphy output power is 40-watts CCS and 54-watts for telegraphy.  
 
Glen, K9STH


Website:  http://k9sth.com


________________________________
 From: Brian Clarke <brianclarke01 at optusnet.com.au>
To: boatanchors at mailman.qth.net; Roger Ruszkowski <flowertime01 at wmconnect.com> 
Sent: Saturday, June 1, 2013 7:20 PM
Subject: Re: [Boatanchors] 1930's era cw transmitter
 

Hello folks,

Push-pull RF PA for AM at HF is most unusual. Most designs, including Dr Drake's ARC-5 and its clones, Collins, General Dynamics and Harris put RF tubes in the PA in parallel.

Why? In push pull, each tube is working half the time - so you won't get 100 W input, let alone output. In parallel, both tubes are working all the time. And the killer? Neutralising push-pull is a bear - so much easier in parallel designs.

The RCA Transmitting tube manual lists 60 W maximum input for CW as ICAS operation for the 807 - less for CCS and for telephony. But if you are in the land of plenty and you can afford the time to keep neutralising the tubes you melt, go right ahead.