[GreenKeys] ST-6 Receive lamp failure - looking for a replacement source

[Roy Morgan]

On Dec 14, 2013, at 1:04 PM, k0bx at arrl.net wrote:

> It looks like the lamps are either 12 or 16 volt.  Here is the diagram of the ST-6.  Scroll down and there is a description of the lamps.
> 
> http://rtty.com/development/tu/st-6/st-6.htm

That description is:

"The lamps should be low-current types. Most 12V lamps are 80-170 mills, and this is really too much for the transistors to handle with only a 10K resistor to their base. We suggest you use Sylvania cartridge indicator lamps - they have one that takes only 15-20 mills at 16 volts, others that take only 35-40 mills at 18V. Both Allied and Newark handle the Sylvania brand, If you must use lamps that require 80 ma. current, change the 10 K resistor to a 4.7K value.”

Roy

Roy Morgan
RoyMorgan at alum.mit.edu
K1LKY Since 1958