[Milsurplus] TCS Question

[brewerj@squared.com]

From: "Ray Fantini" <RAFANTINI@salisbury.edu>
To: <milsurplus@mailman.qth.net>
Subject: [Milsurplus] More TCS

>I am not intending to modify or change the original design of the TCS =
>transmitter, will drop the idea of running the second PA tube, but because =
>I do not have the original AC power supply, I am building a external =
>modern supply and their are legitimate questions on what can safely be =
>supplied as a plate voltage with this radio, if by increasing the plate =
>voltage by a hundred volts or so  you have the benefit of a couple more =
>watts how can that hurt?

I'd be careful about arbitrarily increasing the plate voltage by 25%.
The guys that originally designed this stuff were not stupid. The
answer to this questions lies in the schematic.

> although I do not think I can reach the goal of =
>twenty five watts of AM phone if I did that would be a doubling of power =
>from the twelve watts or so the radio normally produces, that's 3 Db, in =
>retrospect would you decrease by half the power of your transmitters and =
>run them that way? after all its only 3 Db.

If it was a 60 year old radio designed for 12w, absolutely I would. If
you need more power, feed it into a linear, or find a Kenwood something
or other to hotrod.

>One of the aspects of my =
>application of this hobby is to try to get the best efficiency and =
>performance from these designs. but this is all apart from  my point. The =
>real question is if their is any history of failure of the modulation =
>transformer in the TCS and if anyone has any experience in operating them =
>on higher plate voltage and how it will affect its existing components? =
>The idea of additional microphone drive external to the radio to develop =
>higher level of modulation and more peak envelop power sounds good, but =
>brings me back to the same question, what will the modulation transformer =
>take before breakdown?

This seems somewhat akin to asking "What will happen if I try to put a
supercharger on this 1955 Chevy? Will it do 140 MPH, or will it break
down?"

The best answer to your question is: Why would you want to do this?

With all due respect, the result of this experiment will likely be one more
hacked up TCS. You're not likely to get a whole lot of help in this forum
in accomplishing that result.

73 John K5MO