[BC] AM Transmitter For Conversion

[Peter]

On May 8, 2008, at 4:46 PM, rameuser at tmo.blackberry.net wrote:

> That would probably been when there only AM transmitters and the  
> extra letter was unnecessary.
>
> > What is a BT1 ? I never heard of that model
>
> Broadcast Transmitter, before RCA changed the prefix to BTA-

BT pre-FM, pre-TV designation for "Broadcast Transmitter", in which  
case, "AM" was assumed as ALL broadcast was AM, and which it was ...  
originally ... called the "Standard Broadcast Band".

I believe the BT prefix was retained until the present FM and TV  
bands were codified, post-WW-II, after which event, BTA (AM  
Broadcast), BTF (FM Broadcast) and BTL (Low-band [ VHF ] Television  
Broadcast) and BTH (High-band [ VHF ] Television Broadcast) came  
about. Later, BTU (UHF Television Broadcast) was added.

With RCA, the BT? is "interesting", but the "Devil is in the  
details", and that's where one gets down to the "MI" (Master Index)  
number.

In cinema sound, we always talked about the MI-10001 microphone,  
which would ... informally ...  be called the KU-<something>.