[ARC5] BC-230 first run

[Mike Morrow]

> ... what I'm interested in here is how the change to VT-25-A affects
> the schematic, since my set is the AO and accordingly should have used
> the VT-25-A.
>
> Now, am I wrong to rely on that schematic? What discrepancies should I
> be aware of? Does this have any bearing on the coil tap that I pointed out
> elsewhere?

The only change to the schematic of the BC-AO-230 through BC-AS-230 is an "-A" after the "VT-25" tube labels.  The tube operating data tables in the manuals for these five transmitters did not change with introduction of the VT-25-A.

The VT-25-A appears to be electrically identical to the VT-25, but it has some internal mechanical differences.  Apparently these were construction improvements made without notably altering electrical characteristics.  Anyone with some real insight into VT-25 vs. VT-25-A might want to join in.  Do NOT put much faith in anything from the audio-idiot websites where "tubes with thoriated filaments sound better than tubes with oxide-coat filaments."

So...the schematic is fine.  The info on the original tube variants is of historical interest only.

Mike / KK5F