[TMC] SBE-3 data

[roy.morgan at nist.gov]

Quoting telegrapher at att.net:

> ...The SBE -2 uses a 17 Kc and 287 KC.
> 
> The SBE-3 utilizes only a 250 Kc osc. section which explains why my xtal 
> for 3870 ended up on 3890. 

Larry,

Why TMC made this change we can speculate upon, or just put the topic onto the
"Odd Items and Esoterica" list.


> So there needs to be either a new crystal... OR use a VOX 

 No TMC home should be without a VOX!

 
> Thanks to JP and RM for furnishing the SBE schematics.  

The Thanks should go to John Poulton, who apparently scanned and posted the
SBE-3 mNUAL.

> According to the Manual i see, this unit was used with the GPT-10K and 
> has the wide sidebands of 250 cycles through 7.5kc.  Not gonna be good 
> for the hambands.

Just limit the audio bandwidth you feed to the thing.  Do I remmber right that
the SBS's do not have a line input?  Seems odd, and I may well be  mistaken. 
But a line input would let you run all sorts of audio preamplification, mixing,
limiting, bandwidth control and all that. (I plan a bit of all that for the
future.)

Roy


Roy Morgan
7130 Panorama Dr.
Derwood MD 20855