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VTTC modulator schematic question

Original poster: Phil Rembold <prembold@xxxxxxxxx>

Sue,

I know you've moved on to bigger and better things, looking in the
archives found a post you made that had a VTTC modulator schematic. No
grid bias resistors or bypass caps. This is sweet !!!

But I do have some questions about the driver and plate transformers :

For good modulation, how many mA of current runs through your 811 tubes ?
How many volts peek should the driver put on the grid of the 811 tubes ?
For the plate transformer, the wire gauge should be enough to handle
the current of the coil your driving. What primary / secondary turns
ratio is ideal ?
Did you "borrow" these transformers from old audio tube Amps ? Would a
70 Volt line transformer from Radio Shack work or do you think a
person could wind their own ?

Thanks for posting this design.

Phil TCBFW


----- Original Message -----
From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Friday, May 30, 2003 8:38 PM
Subject: Re: Successful SSTC Audio Modulation - SWEET!

> Original poster: "S Gaeta by way of Terry Fritz <teslalist@xxxxxxxxx>"
<sgtporky@xxxxxxxxxxx>
>
> Hi,
>
> The tube coil schematic can be found at
> http://community.webshots.com/photo/8426665/48494920pFtYul
> and a simplified modulator schematic can be found at
> http://community.webshots.com/photo/8426665/48496190jiruxv
> The modulator is not my design. I found it in an old (before 1970) ARRL
> Handbook, but now I can't seem to find it again. When I do I will post it
> since there seems to be an interest.
>
> Sue