[Heath] Light bulbs for HW/SB transceivers

[Kenneth G. Gordon]

On 14 Jan 2013 at 15:06, Ron Oxley wrote:

> The SB-102 dial lamps are #1815 which is a 14 volt lamp.  They are
> wired in parallel across the 12.6 volt filament line.  The lamp used
> for regulation in the LMO power supply is also a #1815.  The meter
> lamp is a #47 which is a 6.3 volt lamp and wired across the 6.3 volt
> portion of the filament line.

Hmmm...well, the SB-102 has a lot of little, and one or two larger, differences 
from the SB-101.

I suppose the series-parallel wiring of the filaments is considerably different 
from the '101 also, then.

I know there are at least 3 different configurations of the "S" meter circuit in 
the '102, among other things.

I also suppose that that #47 lamp being the only one in the circuit in the 
SB-102 is the reason that it is  more than likely burnt out most of the time.

In any case, the HW/SB rigs, with the exception of the SB-102, must have 
#47 pilot lamps installed and NOT #44s. And SOME of those transceivers 
were shipped with #44 lamps by mistake, if the Heathkit Service Bulletins are 
to be believed...

Ken Gordon W7EKB